WO2018054079A1

WO2018054079A1 - Method for storing file, first virtual machine and namenode

Info

Publication number: WO2018054079A1
Application number: PCT/CN2017/085351
Authority: WO
Inventors: 李亿
Original assignee: 华为技术有限公司
Priority date: 2016-09-23
Filing date: 2017-05-22
Publication date: 2018-03-29
Also published as: CN106446159B; CN106446159A

Abstract

A method for storing a file, a first virtual machine and a namenode, which are used for solving the problem of redundant files existing when a distributed file system stores files, and improving system availability. The method comprises: a client transmitting to a namenode a request message for requesting to write to-be-written data into a distributed file system; the namenode transmitting to the client a response message corresponding to the request message, the response message comprising the address of a first virtual machine and the address of a second virtual machine, and indicating that the first virtual machine is a virtual machine among a plurality of virtual machines that has the right to write data into a storage area and that the second virtual machine is a virtual machine among the plurality of virtual machines other than the first virtual machine; the client transmitting the to-be-written data and the address of the second virtual machine to the first virtual machine; the first virtual machine writing the to-be-written data into the storage area shared by the plurality of virtual machines, and generating or updating the metadata of the to-be-written data; the first virtual machine transmitting the generated or updated metadata to the second virtual machine.

Description

Method for storing files, first virtual machine and name node

Technical field

The present invention relates to the field of computer technologies, and in particular, to a method for storing a file, a first virtual machine, and a name node.

Background technique

A distributed file system includes a client, a data node, and a name node; wherein the data node is used to store files and the name node is used to manage files stored on the data nodes. The client can query the files stored in each data node through the name node and obtain the address of each data node, so as to read the file from the data node or write the file to the data node. A data node in a distributed file system can be either a physical server or a virtual machine.

When the data node in the distributed file system is a virtual machine, the virtual hard disk of the virtual machine is provided by the distributed block storage system, and writing the file to the virtual machine actually writes the file to the virtual hard disk of the virtual machine and writes to the virtual hard disk. The file is implemented by writing files to the physical hard disk managed by the distributed block storage system.

In order to ensure the reliability of the file, the distributed file system uses the file copy mechanism when storing files on the virtual hard disk, and saves the same file in N (N is an integer greater than 1) virtual hard disk in the distributed file system; In order to ensure the reliability of the file, the block storage system also uses the file copy mechanism to save the files in the same virtual hard disk in M (M is an integer greater than 1) physical hard disk. Because the file copy mechanism is adopted in both the distributed file system and the distributed block storage system, the number of files actually saved in the same file on the physical hard disk is N*M, resulting in redundancy of file shares. The redundancy of the number of copies of the file saved in the same file wastes storage space and affects the processing performance of the system.

In the prior art, in order to solve the problem of file number redundancy in a distributed file system, the following two methods are generally used: The first method is, for a file to be stored, only in a virtual machine of the distributed file system. Store the file in . In the first method, the file can be accessed only through the virtual machine. If the virtual machine fails, the virtual machine needs to wait for the virtual machine to return to normal before providing the file read and write service to the client again, resulting in a distributed file system. The second method is to use the hot standby mechanism of the virtual machine, that is, to configure the hot standby virtual machine corresponding to the primary virtual machine, and the hot standby virtual machine writes files synchronously with the primary virtual machine. When the primary virtual machine fails, the distributed file system switches to the hot standby virtual machine to continue to provide file read and write services to the client. With the second method, the distributed file system needs a certain waiting time when switching to the hot standby virtual machine, which causes the distributed file system to fail to provide file read and write services to the client during the waiting time, so that the distributed file system is available. Reduced; and the hot standby virtual machine does not provide external services before switching to the primary virtual machine, resulting in wasted resources.

In summary, the existing methods for solving the problem of file number redundancy in a distributed file system may result in low availability of the distributed file system and inability to better solve the problem of file number redundancy.

Summary of the invention

The embodiment of the invention provides a method for storing a file, a first virtual machine and a name node, which are used to solve the problem of redundancy of the number of files existing when the distributed file system stores the file, and improve the availability of the system.

In a first aspect, an embodiment of the present invention provides a method for storing a file in a distributed file system, where The distributed file system includes a name node and a plurality of virtual machines as data nodes, wherein the plurality of virtual machines share the same storage area; the method includes:

The first virtual machine receives the data to be written sent by the client, the address of the second virtual machine, and then writes the received data to be written to the storage area shared by the plurality of virtual machines, and generates or updates the metadata of the data to be written; The first virtual machine sends the metadata generated or updated by the first virtual machine to the second virtual machine according to the received address of the second virtual machine.

The first virtual machine is a virtual machine in the plurality of virtual machines that has the right to write data to the storage area by the name node, and the second virtual machine is a virtual machine other than the first virtual machine among the plurality of virtual machines; The metadata of the data to be written includes, but is not limited to, a storage location of the data to be written, a file name of the data to be written, and a file directory of the data to be written.

According to the above method, since the plurality of virtual machines included in the distributed file system share the same storage area, in the distributed file system, the data to be written written by the first virtual machine in the storage area is only saved in the storage area. . For the data to be written, only multiple copies are saved due to the file copy mechanism adopted by the distributed block storage system, and there is no saved file due to the file copy mechanism adopted by both the distributed file system and the distributed block storage system. The problem of number of copies.

In addition, with the above solution, the first virtual machine of the plurality of virtual machines included in the distributed file system has the right to write data to the storage area, and the second virtual machine of the plurality of virtual machines except the first virtual machine has the slave The storage area reads the permission to write data. Thus, the number of virtual machines available in a distributed file system that can be used to provide clients with services for reading and writing data to be written is multiple. When a virtual machine fails, other virtual machines can provide services for the client to read and write data to be written, so that the availability of the distributed file system is improved, and the hot standby of the virtual machine is avoided in the prior art. There is a waste of resources in the mechanism.

In a possible implementation, before the first virtual machine writes the data to be written to the storage area, the method further includes: the first virtual machine receives the write permission identifier of the first virtual machine sent by the client, and the write permission identifier is a name node. When the client requests the name node to write the data to be written to the distributed file system, it is sent to the client, and is used to specify that the first virtual machine has the right to write the data to be written to the storage area.

With the above solution, a manner is provided in which the client indicates the authority of the first virtual machine to the first virtual machine.

A plurality of virtual machines share a storage area. The multiple virtual machines can be mounted on the same virtual hard disk provided by the distributed block storage system. The virtual hard disk includes a storage area shared by multiple virtual machines.

The metadata of the data to be written sent by the first virtual machine to the second virtual machine has the following two purposes:

First, if the second virtual machine reads the data to be written through its own operating system, the metadata is used by the second virtual machine to generate or update file information recorded in its own operating system, and the file information is used for operating system storage. The data to be written is read in the area.

Second, if the second virtual machine reads the data to be written, the metadata is used by the second virtual machine to read the data to be written from the storage area.

With the above solution, the second virtual machine can read the data to be written in the storage area shared by the multiple virtual machines according to the metadata of the data to be written sent by the first virtual machine.

In a possible implementation manner, the second virtual machine may be designated by the name node to have the right to read the data to be written from the storage area.

In a second aspect, an embodiment of the present invention provides a method for storing a file in a distributed file system, where the distributed file system includes a name node and a plurality of virtual machines as data nodes, and the plurality of virtual machines share the same storage area; Methods include:

After receiving the request message that the client requests to write the data to be written to the distributed file system, the name node sends a response message corresponding to the request message to the client.

The response message sent by the name node to the client includes the address of the first virtual machine and the address of the second virtual machine. In addition, the response message further indicates that the first virtual machine has written to the storage area for multiple virtual machines. A virtual machine of the authority of the data, the second virtual machine being a virtual machine other than the first virtual machine among the plurality of virtual machines.

With the above solution, since the plurality of virtual machines included in the distributed file system share the same storage area, the response message sent by the name node specifies that one of the plurality of virtual machines has data to be written into the shared storage area. Permissions, so data written to a shared storage area will only be saved in that storage area. For the data written to the shared storage area, only multiple copies are saved due to the file copy mechanism adopted by the distributed block storage system, and there is no file copy mechanism due to the distributed file system and the distributed block storage system. The resulting problem of redundant copies of saved files.

Further, in the response message, the first virtual machine of the plurality of virtual machines included in the distributed file system has the right to write data to the storage area, and the second virtual machine of the plurality of virtual machines except the first virtual machine has a slave The storage area reads the permission to write data. Thus, the number of virtual machines available in a distributed file system that can be used to provide clients with services for reading and writing data to be written is multiple. When a virtual machine fails, other virtual machines can provide services for the client to read and write data to be written, so that the availability of the distributed file system is improved, and the hot standby of the virtual machine is avoided in the prior art. There is a waste of resources in the mechanism.

In a possible implementation manner, the response message further indicates that the second virtual machine has the right to read the data to be written from the storage area.

In a possible implementation manner, the name node may indicate the rights of the first virtual machine and the rights of the second virtual machine to the client by using a response message in the following two manners:

In the first mode, the response message sent by the name node to the client further includes a write permission identifier of the first virtual machine and a read permission identifier of the second virtual machine, wherein the write permission identifier and the read permission identifier respectively indicate the first virtual machine Permissions and permissions of the second virtual machine, that is, the write permission identifier is used to specify that the first virtual machine has the right to write data to be written to the storage area, and the read permission identifier is used to specify that the second virtual machine has read from the storage area. Permission to write data.

In the second mode, the address of the first virtual machine and the address of the second virtual machine in the response message sent by the name node to the client are arranged according to a preset rule, and the preset rule indicates the authority of the first virtual machine and the second virtual The authority of the machine, that is, the first virtual machine has the right to write the data to be written to the storage area, and the second virtual machine has the right to read the data to be written from the storage area.

In both manners, two ways are provided for the name node to indicate to the client the rights of the first virtual machine and the rights of the second virtual machine through a response message.

In a possible implementation, a plurality of virtual machines share a storage area. In a specific implementation, the following manners may be adopted: multiple virtual machines mount the same virtual hard disk provided by the distributed block storage system, and the virtual hard disk includes a storage area.

Since there are multiple virtual machines in the distributed file system that can be used to provide services for the client to read and write data to be written, when a virtual machine fails, the other virtual machines can provide read and write for the client. A service that writes data. In the specific implementation, how the name node handles when the virtual machine fails can include the following two situations:

In the first case, when the first virtual machine fails, the name node sends the first update information to the client, where The first update information includes an address of the updated first virtual machine, and the first update information further specifies another virtual machine of the plurality of virtual machines other than the failed first virtual machine as the updated first virtual machine, that is, the specified One of the second virtual machines is the updated first virtual machine, and the updated first virtual machine has the right to write data to the storage area.

In the second case, when the second virtual machine fails, the name node sends the second update information to the client, the second update information includes the address of the updated second virtual machine, and the second update information further specifies multiple virtual Another virtual machine other than the machine serves as the updated second virtual machine, and the updated second virtual machine has the right to read the data to be written from the storage area.

With the above solution, whether the first virtual machine fails or the second virtual machine fails, the name node specifies another virtual machine to replace the failed virtual machine, thereby occurring in the first virtual machine and/or the second virtual machine. In the case of a failure, the distributed file system can still provide services for the client to read and write data, further improving the availability of the distributed file system.

In a third aspect, an embodiment of the present invention provides a method for storing a file in a distributed file system, where the distributed file system includes a name node, multiple virtual machines as data nodes, and multiple virtual machines share the same storage area; include:

The client sends a request message to the name node to write the data to be written to the distributed file system, and then receives the response message corresponding to the request message sent by the name node.

The response message includes an address of the first virtual machine and an address of the second virtual machine. In addition, the response message further indicates that the first virtual machine is a virtual machine having permission to write data to the storage area among the plurality of virtual machines, The second virtual machine is a virtual machine other than the first virtual machine among the plurality of virtual machines.

The client sends the to-be-written data and the address of the second virtual machine to the first virtual machine according to the address of the first virtual machine included in the response message, and indicates the first virtual machine: writing the data to be written, generating or updating the data to be written. Metadata, and transmitting metadata of the data to be written to the second virtual machine according to the address of the second virtual machine.

In the above solution, the distributed file system includes multiple virtual machines sharing the same storage area. Therefore, in the distributed file system, the client instructs the first virtual machine to write the data to be written in the shared storage area only in the storage area. Store one copy. For the data to be written, only multiple copies are saved due to the file copy mechanism adopted by the distributed block storage system, and there is no saved file due to the file copy mechanism adopted by both the distributed file system and the distributed block storage system. The problem of number of copies.

In addition, since the first virtual machine of the plurality of virtual machines included in the distributed file system has the right to write data to the storage area, the second virtual machine of the plurality of virtual machines except the first virtual machine has read from the storage area. Take permission to write data. Thus, the number of virtual machines available in a distributed file system that can be used to provide clients with services for reading and writing data to be written is multiple. When a virtual machine fails, other virtual machines can provide services for the client to read and write data to be written, so that the availability of the distributed file system is improved, and the hot standby of the virtual machine is avoided in the prior art. There is a waste of resources in the mechanism.

In a possible implementation manner, the client can obtain the rights of the first virtual machine and the rights of the second virtual machine by using the response message sent by the received name node in the following two manners:

In the first mode, the response message received by the client further includes a write permission identifier of the first virtual machine and a read permission identifier of the second virtual machine, wherein the write permission identifier and the read permission identifier respectively indicate the permissions of the first virtual machine And the right of the second virtual machine, that is, the write permission identifier is used to specify that the first virtual machine has the right to write the data to be written to the storage area. The read permission identifier is used to specify that the second virtual machine has the right to read the data to be written from the storage area.

In the second mode, the address of the first virtual machine and the address of the second virtual machine in the response message received by the client are arranged according to a preset rule, where the preset rule indicates the authority of the first virtual machine and the second virtual machine. Permissions, that is, the first virtual machine has the right to write data to be written to the storage area, and the second virtual machine has the right to read the data to be written from the storage area.

In these two manners, two ways are provided for the client to obtain the permission of the first virtual machine and the authority of the second virtual machine by receiving the response message.

In a fourth aspect, an embodiment of the present invention provides a method for storing a file in a distributed file system, where the distributed file system includes a name node and a plurality of virtual machines as data nodes, and the plurality of virtual machines share the same storage area; include:

The second virtual machine receives the metadata sent by the first virtual machine. The first virtual machine is a virtual machine in which a name node has a right to write data to the storage area, and the second virtual machine is a virtual machine other than the first virtual machine among the plurality of virtual machines. The metadata is metadata of the data to be written generated or updated after the first virtual machine writes the data to be written to the storage area.

According to the above solution, since the plurality of virtual machines included in the distributed file system share the same storage area, and one of the plurality of virtual machines has the right to write data to the shared storage area, the shared storage is performed. The data written in the area will only be saved in the storage area. For the data written to the shared storage area, only multiple copies are saved due to the file copy mechanism adopted by the distributed block storage system, and there is no file copy mechanism due to the distributed file system and the distributed block storage system. The resulting problem of redundant copies of saved files.

In addition, the first virtual machine of the plurality of virtual machines included in the distributed file system has the right to write data to the storage area, and the second virtual machine of the plurality of virtual machines except the first virtual machine has read from the storage area. Permission to write data. Thus, the number of virtual machines available in a distributed file system that can be used to provide clients with services for reading and writing data to be written is multiple. When a virtual machine fails, other virtual machines can provide services for the client to read and write data to be written, so that the availability of the distributed file system is improved, and the hot standby of the virtual machine is avoided in the prior art. There is a waste of resources in the mechanism.

In a possible implementation manner, the second virtual machine may obtain the read permission identifier of the second virtual machine sent by the client before receiving the metadata sent by the first virtual machine. The read permission identifier is sent to the client when the client requests the name node to write the data to be written to the distributed file system, and the read permission identifier is used to specify that the second virtual machine has read the data to be written from the storage area. permission.

After the second virtual machine receives the metadata sent by the first virtual machine, the data to be written in the storage area shared by the plurality of virtual machines may be read according to the received metadata, and the following manner may be adopted:

The first type, if the second virtual machine reads the data to be written through its own operating system, the second virtual machine is based on the number of elements. According to the file information recorded in the operating system of the own generation or update, the file information can be used by the operating system to read the data to be written from the storage area.

Second, if the second virtual machine reads the data to be written, the second virtual machine reads the data to be written from the storage area according to the metadata.

In a possible implementation, the second virtual machine is designated by the name node to have the right to read the data to be written from the storage area.

In a fifth aspect, an embodiment of the present invention provides a first virtual machine in a distributed file system, where the distributed file system includes a name node and multiple virtual machines as data nodes, and multiple virtual machines share the same storage area. A virtual machine specifies, by a name node, a virtual machine having a right to write data to the storage area among the plurality of virtual machines; the first virtual machine includes:

a receiving module, configured to receive data to be written by the client, and an address of the second virtual machine, where the second virtual machine is a virtual machine other than the first virtual machine;

a processing module, configured to write, to the storage area, data to be written received by the receiving module, and generate or update metadata of the data to be written;

And a sending module, configured to send, to the second virtual machine, the processing module to generate or update the metadata according to the address of the second virtual machine received by the receiving module.

The metadata of the data to be written includes, but is not limited to, a storage location of the data to be written, a file name of the data to be written, and a file directory of the data to be written.

With the above solution, since the plurality of virtual machines included in the distributed file system share the same storage area, in the distributed file system, the data to be written written by the processing module to the storage area is only saved in the storage area. For the data to be written, only multiple copies are saved due to the file copy mechanism adopted by the distributed block storage system, and there is no saved file due to the file copy mechanism adopted by both the distributed file system and the distributed block storage system. The problem of number of copies.

In addition, with the above method, the first virtual machine of the plurality of virtual machines included in the distributed file system has the right to write data to the storage area, and the second virtual machine of the plurality of virtual machines except the first virtual machine has the slave The storage area reads the permission to write data. Thus, the number of virtual machines available in a distributed file system that can be used to provide clients with services for reading and writing data to be written is multiple. When a virtual machine fails, other virtual machines can provide services for the client to read and write data to be written, so that the availability of the distributed file system is improved, and the hot standby of the virtual machine is avoided in the prior art. There is a waste of resources in the mechanism.

In a possible implementation manner, the receiving module is further configured to: before the processing module writes the data to be written to the storage area, receive a write permission identifier of the first virtual machine sent by the client, where the write permission identifier is a name node at the client When the end node requests the write to the distributed file system to write the data to be written to the client, the write permission identifier is used to specify that the first virtual machine has the right to write the data to be written to the storage area.

With the above solution, a manner is provided in which the first virtual machine learns its own authority from the client.

Multiple virtual machines share a storage area. In a specific implementation, the following methods can be adopted: multiple virtual machines mount the same virtual hard disk provided by the distributed block storage system, and the virtual hard disk includes a storage area.

The metadata of the data to be written sent by the sending module to the second virtual machine has the following two purposes:

With the above solution, the second virtual machine can read the data to be written in the storage area shared by the plurality of virtual machines according to the metadata of the data to be written sent by the sending module.

In a sixth aspect, an embodiment of the present invention provides a name node in a distributed file system, where the distributed file system includes a name node and multiple virtual machines as data nodes, and multiple virtual machines share the same storage area; include:

a receiving module, configured to receive a request message that the client requests to write data to be written to the distributed file system;

a sending module, configured to send, to the client, a response message corresponding to the request message received by the receiving module, where the response message includes an address of the first virtual machine and an address of the second virtual machine, and further, the response message further indicates that the first virtual machine is One of the plurality of virtual machines having the authority to write data to the storage area, and the second virtual machine is a virtual machine other than the first virtual machine among the plurality of virtual machines.

With the above solution, since the plurality of virtual machines included in the distributed file system share the same storage area, the response message sent by the name node specifies that one of the plurality of virtual machines has data to be written into the shared storage area. Permissions, so data written by the processing module to the shared storage area will only be saved in the storage area. For the data written to the shared storage area, only multiple copies are saved due to the file copy mechanism adopted by the distributed block storage system, and there is no file copy mechanism due to the distributed file system and the distributed block storage system. The resulting problem of redundant copies of saved files.

In a possible implementation manner, the response message sent by the sending module may indicate the rights of the first virtual machine and the rights of the second virtual machine to the client in the following two manners:

First way

The response message sent by the sending module to the client further includes a write permission identifier of the first virtual machine and a read permission identifier of the second virtual machine, wherein the write permission identifier and the read permission identifier respectively indicate the authority of the first virtual machine and the second The permission of the virtual machine, that is, the write permission identifier is used to specify that the first virtual machine has the right to write the data to be written to the storage area, and the read permission identifier is used to specify that the second virtual machine has the right to read the data to be written from the storage area. .

Second way

The address of the first virtual machine and the address of the second virtual machine in the response message sent by the sending module to the client are arranged according to a preset rule, where the preset rule indicates the right of the first virtual machine and the right of the second virtual machine, that is, The first virtual machine has the right to write data to be written to the storage area, and the second virtual machine has the right to read the data to be written from the storage area.

In these two manners, two methods are provided for the response message sent by the sending module to indicate to the client the rights of the first virtual machine and the rights of the second virtual machine.

Since there are multiple virtual machines in the distributed file system that can be used to provide services for the client to read and write data to be written, when a virtual machine fails, the other virtual machines can provide read and write for the client. A service that writes data. In specific implementation, how the sending module handles when the virtual machine fails may include the following two situations:

In the first case, when the first virtual machine fails, the first update information is sent to the client, where the first update information includes an address of the updated first virtual machine, and the first update information is also specified in multiple virtual machines. Another virtual machine other than the failed first virtual machine serves as the updated first virtual machine, and the updated first virtual machine has the right to write data to the storage area.

In the second case, when the second virtual machine fails, the second update information is sent to the client, where the second update information includes the address of the updated second virtual machine, and the second update information is further specified by multiple virtual machines. Another virtual machine is the updated second virtual machine, and the updated second virtual machine has the right to read the data to be written from the storage area.

With the above solution, whether the first virtual machine fails or the second virtual machine fails, the sending module specifies another virtual machine to replace the failed virtual machine, thereby occurring in the first virtual machine and/or the second virtual machine. In the case of a failure, the distributed file system can still provide services for the client to read and write data, further improving the availability of the distributed file system.

In a seventh aspect, the embodiment of the present invention provides a client, where the distributed file system includes a name node and multiple virtual machines as data nodes, and multiple virtual machines share the same storage area; the client includes:

a sending module, configured to send, to the name node, a request message for writing a data to be written to the distributed file system;

a receiving module, configured to receive a response message corresponding to the request message sent by the name node;

The response message includes an address of the first virtual machine and an address of the second virtual machine. In addition, the response message further indicates that the first virtual machine is a virtual machine having permission to write data to the storage area among the plurality of virtual machines, The second virtual machine is a virtual machine other than the first virtual machine among the plurality of virtual machines;

The sending module is further configured to send the to-be-written data and the address of the second virtual machine to the first virtual machine according to the address of the first virtual machine included in the response message received by the receiving module, and instruct the first virtual machine to: write the data to be written Generating or updating metadata of the data to be written, and transmitting metadata of the data to be written to the second virtual machine according to the address of the second virtual machine included in the response message received by the receiving module.

In the above solution, the distributed file system includes multiple virtual machines sharing the same storage area. Therefore, in the distributed file system, the sending module instructs the first virtual machine to write the data to be written in the shared storage area only in the storage area. Store one copy. For the data to be written, only multiple copies are saved due to the file copy mechanism adopted by the distributed block storage system, and there is no saved file due to the file copy mechanism adopted by both the distributed file system and the distributed block storage system. The problem of number of copies.

In a possible implementation, the receiving module can obtain the rights of the first virtual machine and the rights of the second virtual machine by using the response message sent by the name node:

In the first manner, the response message received by the receiving module further includes a write permission identifier of the first virtual machine and a read permission identifier of the second virtual machine, wherein the write permission identifier and the read permission identifier respectively indicate the permissions of the first virtual machine And the permission of the second virtual machine, that is, the write permission identifier is used to specify that the first virtual machine has the right to write the data to be written to the storage area, and the read permission identifier is used to specify that the second virtual machine has read from the storage area to be written. Permissions for data.

In a second manner, the address of the first virtual machine and the address of the second virtual machine in the response message received by the receiving module are arranged according to a preset rule, where the preset rule indicates the authority of the first virtual machine and the second virtual machine. Permissions, that is, the first virtual machine has the right to write data to be written to the storage area, and the second virtual machine has the right to read the data to be written from the storage area.

In both manners, the receiving module provides two ways of obtaining the permission of the first virtual machine and the authority of the second virtual machine by receiving the response message.

An eighth aspect of the present invention provides a second virtual machine in a distributed file system, where the distributed file system includes a name node and a plurality of virtual machines as data nodes, and the plurality of virtual machines share the same storage area; The second virtual machine includes:

The receiving module is configured to receive metadata sent by the first virtual machine. The first virtual machine is a virtual machine in which a name node has a right to write data to the storage area, and the second virtual machine is a virtual machine other than the first virtual machine among the plurality of virtual machines. The metadata is metadata of the data to be written generated or updated after the first virtual machine writes the data to be written to the storage area.

In addition, the first virtual machine of the plurality of virtual machines included in the distributed file system has the right to write data to the storage area, and the second virtual machine of the plurality of virtual machines except the first virtual machine has read from the storage area. Permission to write data. Thus, the number of virtual machines available in a distributed file system that can be used to provide clients with services for reading and writing data to be written is multiple. When a virtual machine fails, the other virtual machine can provide the client with read and write data to be written. The service improves the availability of the distributed file system, and also avoids the waste of resources in the prior art when the virtual machine hot standby mechanism is adopted.

In a possible implementation, the receiving module may obtain the permission of the second virtual machine in the following manner: the receiving module receives the read permission identifier of the second virtual machine sent by the client before receiving the metadata sent by the first virtual machine. The read permission identifier is sent to the client when the client requests the name node to write the data to be written to the distributed file system, and the read permission identifier is used to specify that the second virtual machine has read the data to be written from the storage area. permission.

In a possible implementation manner, the second virtual machine further includes a processing module. After the receiving module receives the metadata sent by the first virtual machine, the processing module may read the data to be written in the storage area shared by the plurality of virtual machines according to the received metadata, and the processing module may adopt the following manner:

First, after the receiving module receives the metadata sent by the first virtual machine, if the second virtual machine reads the data to be written through its own operating system, the processing module generates or updates the record recorded in its own operating system according to the metadata. File information, which is used by the operating system to read data to be written from the storage area.

Second, if the second virtual machine reads the data to be written, the processing module reads the data to be written from the storage area according to the metadata.

With the above solution, the processing module can read the data to be written in the storage area shared by the plurality of virtual machines according to the metadata of the data to be written sent by the first virtual machine.

According to a ninth aspect, a computer readable storage medium is provided, where computer execution instructions are stored, and when at least one processor of a computing node executes the computer to execute an instruction, the computing node executes the first aspect or the first Various possible aspects of the aspects are provided by the method provided, or the method provided by the various possible designs of the second or second aspect described above, or the methods provided by the various possible designs of the third or third aspect described above.

In a tenth aspect, a computer program product is provided, the computer program product comprising computer executed instructions stored in a computer readable storage medium. At least one processor of the computing node can read the computer-executable instructions from a computer-readable storage medium, the at least one processor executing the computer-executing instructions, such that the computing node implements the first aspect or the methods provided by the various possible designs of the first aspect Or the method provided by the various possible designs of the second aspect or the second aspect described above, or the method provided by the various possible designs of the third aspect or the third aspect described above.

DRAWINGS

1 is a schematic diagram of a connection relationship between a name node, a client, and multiple data nodes in a distributed file system according to an embodiment of the present invention;

2 is a schematic diagram of a connection relationship between a distributed file system and a distributed block storage system according to an embodiment of the present invention;

3 is a schematic flowchart of a method for storing a file in a distributed file system according to an embodiment of the present invention;

4 is a schematic structural diagram of a distributed file system and a distributed block storage system using the method for storing files shown in FIG. 3;

FIG. 5 is a schematic structural diagram of a first virtual machine according to an embodiment; FIG.

FIG. 6 is a schematic structural diagram of another first virtual machine according to an embodiment; FIG.

FIG. 7 is a schematic structural diagram of a name node according to an embodiment; FIG.

FIG. 8 is a schematic structural diagram of another name node according to an embodiment; FIG.

FIG. 9 is a schematic structural diagram of a client provided by the embodiment; FIG.

FIG. 10 is a schematic structural diagram of another client provided by the embodiment; FIG.

FIG. 11 is a schematic structural diagram of a second virtual machine according to an embodiment; FIG.

FIG. 12 is a schematic structural diagram of another second virtual machine according to an embodiment; FIG.

FIG. 13 is a schematic structural diagram of a distributed file system according to an embodiment of the present invention.

detailed description

In order to better understand the above objects, aspects and advantages of embodiments of the present invention, a detailed description is provided below. The detailed description sets forth various embodiments of the devices and/or methods in the <RTIgt; In these block diagrams, flowcharts, and/or examples, one or more functions and/or operations are included. Those skilled in the art will appreciate that the various functions and/or operations within the block diagrams, flowcharts or examples can be implemented individually or collectively by various hardware, software, firmware, or by any of hardware, software and firmware. Combined implementation.

The embodiment of the invention relates to a distributed file system. The distributed file system is described in detail below.

As shown in Figure 1, a distributed file system can include a name node and multiple data nodes. Depending on the application of the distributed file system, the name node may also be referred to as a master server or other name. Correspondingly, the data node may also be referred to as a data server or other name. It should be noted that only the distributed file system includes a client scenario in FIG. 1 . In practice, a distributed file system may include multiple clients.

The name node is used to manage multiple data nodes, the name node records information of files stored in each data node (such as metadata files), the service status of each data node, etc.; the data node is used to store files when the client When the file is read and written, the client first requests the name node to obtain the index information of the data node, and then accesses the corresponding data node according to the requested index information to perform file reading and writing. Files may be synchronized between multiple data nodes. For example, when a file needs to be written in two data nodes, one of the data nodes can be written first, and then the data node synchronizes the file to another data node. In addition, information interaction between the name node and the data node is also possible.

The name node, the data node, and the client may configure the corresponding function implementation on any of the following computing devices. The computing capable device may be a physical device or a virtual device; for example, the physical device may be a personal computer, a notebook computer, a mainframe, a networked computer, a handheld computer, a personal digital assistant, a workstation, etc., and the virtual device may be deployed in a physical device. A virtual machine or container in the device.

Referring to FIG. 2, when the data node is a virtual machine, the virtual hard disk of the virtual machine is provided by the distributed block storage system, and the distributed block storage system manages multiple physical hard disks, and the file written to the virtual hard disk of the virtual machine is actually distributed. The file is written to the physical hard disk managed by the block storage system.

Referring to Figure 2, in order to ensure its own reliability, the distributed file system generally uses a file copy mechanism when storing files. For example, when storing a file, the file is stored on two data nodes, that is, stored in a virtual On the machine 1 and the virtual machine 2; in order to ensure the reliability of the distributed block storage system, the file copy mechanism is also adopted when storing the files of the virtual machine, for example, when the file of the virtual machine 1 is stored, respectively, in the physical The physical hard disk of the server 1, the physical hard disk 3 of the physical server 2, and the physical hard disk 5 of the physical server 3 store the file, and are stored in the physical hard disk 2 of the physical server 1 when the file of the virtual machine 2 is stored. The file is stored on the physical hard disk 4 of the physical server 2 and the physical hard disk 6 of the physical server 3. In this way, since the distributed file system and the distributed block storage system both adopt the file copy mechanism, the file is saved in six copies on the physical hard disk managed by the distributed block storage system. Obviously, the redundancy of the file number saved for the same file will waste storage space and affect the processing performance of the system.

It should be noted that, in order to explain the operation of the distributed file system when storing a certain file, only two virtual machines are shown in the distributed file system of FIG. 2, and each virtual machine includes one virtual hard disk; Only three physical servers are shown in the block storage system, each containing two physical hard disks. In actual implementation, the distributed file system can store multiple files, so the number of virtual machines included in the distributed file system is not limited, and the number of virtual hard disks included in each virtual machine is not limited; The number of physical servers included in the block storage system is not limited, and the number of physical hard disks included in each physical server is not limited.

In order to solve the problem of the redundancy of the file number in the distributed file system, the embodiment of the present invention provides a method for storing a file in a distributed file system, where the distributed file system includes a name node and multiple virtual machines as data nodes. Among them, multiple virtual machines share the same storage area. As shown in FIG. 3, the method includes:

S301: The client sends a request message to the name node to write to the distributed file system to write data to be written.

The data to be written may be video data, audio data, document data or other binary data. The granularity of the data to be written can be a file, a data block, or other granularity. The number of data to be written may be one or more. As long as one or more data is written to the distributed file system after the method shown in FIG. 3 is executed once, the one or more data can be regarded as to be written. data.

S302: The name node sends a response message corresponding to the request message to the client.

The response message includes an address of the first virtual machine and an address of the second virtual machine, and the response message further indicates that the first virtual machine is a virtual machine having the right to write data to the storage area among the plurality of virtual machines, and the second virtual The machine is a virtual machine other than the first virtual machine among the plurality of virtual machines.

The number of the first virtual machines must be one; the number of the second virtual machines may be one or more, and the number of the second virtual machines is not limited in the embodiment of the present invention.

In the embodiment of the present invention, only one virtual machine of the plurality of virtual machines has the right to write data to the storage area, because the reason is: if there are multiple virtual machines for writing data to be written, then when the client wants to When the distributed file system writes data to be written, multiple virtual machines receive an instruction to write data to be written; since multiple virtual machines share the same storage area, the write data to be written received by multiple virtual machines The instruction will instruct multiple virtual machines to write the data to be written to the same storage area at the same time. This will cause the instruction to write the data to be written to be indistinguishable from which virtual machine should write the data to be written, resulting in writing the data to be written. The instructions cannot be executed. In addition, only one virtual machine writes data to be written, ensuring that only one data to be written is written in the stage of writing data in the distributed system. Compared with the prior art, in the distributed data writing phase, multiple writes are to be written. Data reduces data redundancy.

The reason why the number of the second virtual machines in the embodiment of the present invention may be multiple is that when there are multiple clients to read the data to be written, the second virtual machine can be read to improve the client reading. The efficiency of the data to be written. In addition, after obtaining the metadata of the to-be-written data sent by the first virtual machine, the second virtual machine may directly access the distributed block storage system. The data to be written is read by the system to avoid the situation that the prior art fails to read the data to be written when the first virtual machine fails.

According to the limitation of the number of the first virtual machine in the embodiment of the present invention, the response message sent by the name node to the client may only indicate that the first virtual machine has the right to write data to the storage area, without indicating the second virtual machine. Permission, the reason is: since only one virtual machine of the plurality of virtual machines has the right to write data to the storage area, when the response message indicates that the first virtual machine of the plurality of virtual machines has the data written to the storage area Permission, then the second virtual machine other than the first virtual machine among the plurality of virtual machines has the right to read the data to be written from the storage area by default.

Optionally, the response message further indicates that the second virtual machine has permission to read data to be written from the stored area.

In S302, the rights of the first virtual machine indicated by the response message and the rights of the second virtual machine are only for the data to be written. The first virtual machine and the second virtual machine share a storage area in which data to be written is written. For example, when the data to be written 1 is stored in the distributed file system, the response message indicates that the virtual machine 1 is the first virtual machine, the virtual machine 2 is the second virtual machine, and the virtual machine 1 writes the data to be written 1 to the virtual machine 1 In the storage area 1, the metadata of the data to be written 1 is then sent to the virtual machine 2, wherein the virtual machine 2 shares the storage area 1 with the virtual machine 1; when the data to be written 2 is stored to the distributed file system, the response The message indicates that the virtual machine 1 is the first virtual machine, and the virtual machine 3 is the second virtual machine. The virtual machine 1 writes the data to be written 2 into the storage area 2 of the virtual machine 1, and then sends the metadata of the data to be written 2 to The virtual machine 3, wherein the virtual machine 3 shares the storage area 2 with the virtual machine 1.

S303: The client sends the to-be-written data and the address of the second virtual machine to the first virtual machine according to the address of the first virtual machine.

The client sends the to-be-written data to the first virtual machine and the address of the second virtual machine is used to instruct the first virtual machine to write the data to be written, generate or update the metadata to be written, and according to the second virtual machine. The address sends the metadata of the data to be written to the second virtual machine.

S304: The first virtual machine writes data to be written to the storage area shared by the plurality of virtual machines, and generates or updates metadata of the data to be written.

The metadata of the data to be written may be used by the first virtual machine and the second virtual machine to read data to be written from the storage area shared by the plurality of virtual machines according to the metadata; the metadata of the data to be written includes but is not limited to: The storage location of the write data, the name of the data to be written, and the directory of the data to be written.

S305: The first virtual machine sends the generated or updated metadata to the second virtual machine according to the address of the second virtual machine.

It should be noted that the distributed file system may generally include a client or may not include a client. If the distributed file system includes a client, the number of clients includes, but is not limited to, one. In the embodiment of the present invention, in order to more clearly describe the interaction between the client, the name node, the first virtual machine, and the second virtual machine, the client is included in the distributed file system. In actual implementation, the distributed file system may not include the client. In this case, the embodiment of the present invention may be regarded as interaction between the client and the distributed file system.

Optionally, the distributed file system includes multiple virtual machines that mount the same virtual hard disk provided by the distributed block storage system, where the virtual hard disk includes a storage area shared by multiple virtual machines.

According to the method for storing files in the distributed file system shown in FIG. 3, since the plurality of virtual machines included in the distributed file system share the same storage area, in the distributed file system, the data to be written is only in the storage area. Store one copy. For the data to be written, only multiple copies are saved due to the file copy mechanism adopted by the distributed block storage system, and there is no saved file due to the file copy mechanism adopted by both the distributed file system and the distributed block storage system. The problem of number of copies.

Further, in the method of storing a file in the distributed file system shown in FIG. 3, the first virtual machine among the plurality of virtual machines included in the distributed file system has the authority to write data to the storage area, and the plurality of virtual machines The second virtual machine other than the first virtual machine has the right to read the data to be written from the storage area. Thus, the number of virtual machines available in a distributed file system that can be used to provide clients with services for reading and writing data to be written is multiple. When a virtual machine fails, other virtual machines can provide services for the client to read and write data to be written, so that the availability of the distributed file system is improved, and the hot standby of the virtual machine is avoided in the prior art. There is a waste of resources in the mechanism.

In order to more vividly explain how the method shown in FIG. 3 solves the problem of storing file number redundancy and improving the availability of the system, the method shown in FIG. 3 is now applied to the distributed file system and the distributed block storage system. A distributed file system and a distributed block storage system using the method shown in FIG. 3 can be as shown in FIG. The distributed file system shown in FIG. 4 includes a first virtual machine, a second virtual machine, a client, and a name node. In actual implementation, there is no limit to the number of second virtual machines and the number of clients. The distributed block storage system shown in Figure 4 contains three physical servers, each containing two physical hard disks.

The first virtual machine has the right to write data to the storage area, and the second virtual machine has the right to read the data to be written from the storage area. Since the first virtual machine and the second virtual machine share the same storage area, the first virtual machine and the second virtual share can share the same virtual hard disk 1. The first virtual machine can write the data to be written to the virtual hard disk 1. The second virtual machine can read the data to be written from the virtual hard disk 1. Therefore, the data to be written is only stored in the distributed file system, that is, stored in the virtual hard disk 1. The data to be written can be stored in the distributed block storage system, for example, the physical hard disk 1 of the physical server 1 is separately stored. The physical hard disk 3 of the physical server 2 and the physical hard disk 5 of the physical server 3. Thus, the data to be written is only saved in the physical hard disk by three copies. The same file in the distributed file system and the distributed block storage system shown in FIG. 2 is stored in the physical hard disk by six copies. In contrast, the distributed file system shown in FIG. 4 is used after the method shown in FIG. The data to be written in the distributed block storage system is only saved in the physical hard disk by three copies, thereby greatly reducing the number of copies of the file and solving the problem of redundancy of the file number saved in the distributed file system.

In addition, in FIG. 4, the first virtual machine can be used to write data to be written and read data to be written, and the second virtual machine can be used to read data to be written, so that when one of the virtual machines fails, the other virtual machine can be used. A non-failed virtual machine provides the client with services to read and write data to be written, improving system availability.

Further, after receiving the metadata of the data to be written sent by the first virtual machine, whether the second virtual machine needs to generate or update the file information recorded in its own operating system may be classified into the following two cases:

First case

If the first virtual machine writes the data to be written to the storage area shared by the plurality of virtual machines, the data is written by the operating system of the first virtual machine, and the client needs to read the data to be written by using the second virtual machine. The operating system of the second virtual machine needs to be read or updated according to the metadata of the data to be written, so that the operating system of the second virtual machine can be implemented from the storage area. Read the data to be written. The file information is used by an operating system of the second virtual machine to read the to-be-written data from the storage area. There are two ways to update the file information in the operating system of the second virtual machine. First, if the operating system of the second virtual machine can learn the change of the data in the storage area, the file of the data to be written can be updated by itself. The second operating system of the second virtual machine can update the file information of the data to be written according to the metadata of the data to be written sent by the first virtual machine.

Second case

When the first virtual machine writes the data to be written to the storage area shared by the plurality of virtual machines, the storage area is directly written, instead of being written by the operating system of the first virtual machine, the client can pass the second virtual machine. The data to be written in the shared storage area is directly read without being read by the operating system of the second virtual machine. At this time, the second virtual machine does not need to generate or update the file information recorded in the operating system according to the metadata of the data to be written, and the second virtual machine can read from the storage area according to the metadata of the data to be written. Waiting for data to be written.

In S302, the name node needs to indicate, by the corresponding message, that the first virtual machine is a virtual machine having the right to write data to the storage area among the plurality of virtual machines, and the second virtual machine is the first virtual machine among the plurality of virtual machines. The virtual machine other than the virtual machine, that is, after the operation of the above S302, the client can obtain not only the address of the first virtual machine and the address of the second virtual machine, but also the first virtual machine has the right to write data to the storage area. The second virtual machine has the right to read data to be written from the storage area. The manner in which the name node notifies the client of the rights of the first virtual machine and the second virtual machine includes but is not limited to the following two types:

First way

In S302, the response message sent by the name node to the client further includes a write permission identifier of the first virtual machine and a read permission identifier of the second virtual machine, where the write permission identifier is used to specify that the first virtual machine has a write to the storage area. The permission to write data, the read permission identifier is used to specify that the second virtual machine has the right to read the data to be written from the storage area. The client learns the rights of the first virtual machine and the second virtual machine according to the write permission identifier and the read permission identifier, and sends the write permission identifier to the first virtual machine, and sends the read permission identifier to the second virtual machine, that is, multiple virtual machines The respective permissions of the machine are sent to the corresponding virtual machine.

The process of sending the write permission identifier to the first virtual machine by the client may be performed before S303 or after S303, or simultaneously with S303, that is, the write permission identifier, the data to be written, and the second virtual The address of the machine is sent to the first virtual machine. The embodiment of the present invention does not limit the order of execution of the two steps. Similarly, the client can send the read permission identifier to the second virtual machine.

Second way

The address of the first virtual machine and the address of the second virtual machine are arranged according to a preset rule in the response message, where the preset rule is used to specify that the first virtual machine has the right to write the data to be written to the storage area, and the second virtual The machine has the right to read data to be written from the storage area.

The preset rule may be an order of addresses of virtual machines included in the response message. For example, the name node and the client may agree in advance that the first address sent by the name node to the client is the address of the first virtual machine, and the client may determine after receiving the addresses of the multiple virtual machines included in the response message. The first address is the address of the first virtual machine having the right to write data to the storage area, and the remaining addresses are the addresses of the second virtual machine having the right to read the data to be written from the storage area.

As mentioned above, there are a plurality of virtual machines that can be used to provide a client with a service for reading and writing data to be written in a distributed file system. When a virtual machine fails, other virtual machines can provide services for the client to read and write data to be written, thereby improving the availability of the distributed file system. The following explains how to operate the virtual machine of the distributed file system after it fails.

In a distributed file system, the method for detecting a failure of a virtual machine includes but is not limited to the following three types: first, the name node detects that a virtual machine has failed; second, the client reads through a virtual machine. If the data is read or written, if the data read/write process cannot be completed, it is determined that the virtual machine is faulty, and the client reports the failure of the virtual machine to the name node. Third, the virtual machine periodically performs a self-test. When a virtual machine is discovered When the fault occurs, the fault message is reported to the name node or reported to the name node through the client. Therefore, when a virtual machine in the distributed file system fails, the name node can learn the failure message of the virtual machine in the above three ways, and then take corresponding operations to avoid the distributed file system cannot provide the client. The case of data read and write services.

In the embodiment of the present invention, the failure of the virtual machine of the distributed file system may be classified into the following two cases:

The first case: the first virtual machine fails

When the first virtual machine fails, the name node sends a first update message to the client, where the first update message includes an updated address of the first virtual machine, where the first update message specifies a failure of the plurality of virtual machines. Another virtual machine other than the first virtual machine serves as the updated first virtual machine, that is, the first virtual machine indicating the update has the right to write data to the storage area shared by the plurality of virtual machines; thus, the client needs to write data. When it is to be written, it can be written by the updated first virtual machine.

In this method, when the first virtual machine fails, the name node specifies another virtual machine other than the failed first virtual machine among the plurality of virtual machines as the updated first virtual machine, that is, the first indicating the update. The virtual machine has the right to write data to the storage area shared by multiple virtual machines. When the client wants to write data, the virtual machine can write through the updated first virtual machine. When the client wants to read data, the virtual machine can pass the first The second virtual machine reads or reads through the updated first virtual machine.

In summary, in this way, when the first virtual machine fails, the client does not affect the writing or reading of data by the client, thereby improving the availability of the system.

As described above, the number of the second virtual machines may be one or more. When the number of the second virtual machines is one, if the first virtual machine fails, the following method may be further performed after executing the foregoing method. The name node specifies one or more updated second virtual machines in addition to the plurality of virtual machines included in the distributed file system, and the updated second virtual machine has the right to read the data to be written from the storage area, and the updated second The virtual machine shares the same storage area with the plurality of virtual machines included in the distributed file system; the name node indicates to the client that the updated second virtual machine has the right to read the data to be written from the storage area. After receiving the indication of the name node, the client notifies the updated first virtual machine: the metadata of the data to be written is sent to the updated second virtual machine. In this way, when the client wants to read the data to be written, it can be read not only by the second virtual machine but also by the updated second virtual machine.

The name node specifies the updated second virtual machine outside the plurality of virtual machines included in the distributed file system to have the right to read the data to be written from the storage area. When there are multiple clients that need to read the data to be written, the client Not only can be read by the second virtual machine, but also read by the updated second virtual machine, which improves the efficiency of the client reading the data to be written.

The second case: the second virtual machine fails

When the second virtual machine fails, the name node sends the second update information to the client, the second update information includes the address of the updated second virtual machine, and the second update information specifies another virtual machine other than the plurality of virtual machines. The updated second virtual machine has the right to read the data to be written from the storage area. The updated second virtual machine shares the same storage area as the plurality of virtual machines included in the distributed file system. After the name node indicates to the client that the updated second virtual machine has the right to read the data to be written from the storage area, the client notifies the first virtual machine according to the indication of the name node: sending the metadata of the data to be written to the updated Two virtual machines.

After receiving the notification message sent by the client, the first virtual machine may send the metadata of the data to be written to the updated second virtual machine according to the indication of the notification message. In this way, when the client wants to read the data to be written, it can not only pass The second virtual machine that has not failed can be read or read by the first virtual machine, and can also be read by the updated second virtual machine.

In this way, when the second virtual machine fails, the name node specifies that the updated second virtual machine has the right to read the data to be written from the storage area, and then the first time when the client wants to write the data to be written The virtual machine writes, when the client wants to read the data to be written, can be read not only by the first virtual machine and the second virtual machine that has not failed, but also by the updated second virtual machine. In summary, in this method, when the first virtual machine fails, the client does not affect the writing or reading of the data to be written by the client, thereby improving the availability of the system.

The method for storing files in the distributed file system provided by the embodiment of the present invention can solve the problem of redundancy of files stored in the distributed file system. In addition, when a certain virtual machine in the distributed file system fails, the method for storing files in the distributed file system provided by the embodiment of the present invention does not affect the client to read or write files, thereby improving system availability. .

The embodiment of the present invention provides a first virtual machine in a distributed file system, where the distributed file system includes a name node and a plurality of virtual machines as data nodes, and the plurality of virtual machines share the same storage area, and the first virtual machine is A virtual machine in a plurality of virtual machines that is designated by a name node to have data to write to the storage area. As shown in FIG. 5, the first virtual machine 500 includes:

The receiving module 501 is configured to receive data to be written sent by the client, and an address of the second virtual machine, where the second virtual machine is a virtual machine other than the first virtual machine.

The processing module 502 is configured to write, to the storage area, the data to be written received by the receiving module 501, and generate or update metadata of the data to be written;

The sending module 503 is configured to send or update the metadata to the second virtual machine sending processing module 502 according to the address of the second virtual machine received by the receiving module 501.

Optionally, the receiving module 501 is further configured to: before the processing module 502 writes the data to be written to the storage area, receive the write permission identifier of the first virtual machine sent by the client.

The write permission identifier is sent to the client when the client requests the name node to write the data to be written to the distributed file system, and the write permission identifier is used to specify that the first virtual machine has written to the storage area to be written. Permissions for data.

Optionally, multiple virtual machines mount the same virtual hard disk provided by the distributed block storage system, and the virtual hard disk includes a storage area.

Optionally, if the second virtual machine reads the data to be written by using its own operating system, the metadata is used by the second virtual machine to generate or update file information recorded in its own operating system, and the file information is used by the operating system from the storage. The data to be written is read in the area; or if the second virtual machine reads the data to be written, the metadata is used by the second virtual machine to read the data to be written from the storage area.

Optionally, the second virtual machine is designated by the name node to have read access to the data to be written from the storage area.

The first virtual machine 500 provided by the embodiment of the present invention can solve the problem of redundancy of files stored in the distributed file system. In addition, when a certain virtual machine in the distributed file system fails, the operation of the first virtual machine 500 provided by the embodiment of the present invention may cause the failure of the virtual machine to not affect the client to read or write the file. Increased system availability.

It should be noted that the first virtual machine 500 provided by the embodiment of the present invention may be used to perform operations performed by the first virtual machine in the method for storing files in the distributed file system shown in FIG. 3, and the first virtual machine 500 does not explain in detail. Description For the implementation, refer to the related description in the method for storing files in the distributed file system shown in FIG. 3.

It should be noted that the division of the module in the embodiment of the present invention is schematic, and is only a logical function division, and the actual implementation may have another division manner. In addition, each functional module in each embodiment of the present application may be integrated into one processing module, or each module may exist physically separately, or two or more modules may be integrated into one module. The above integrated modules can be implemented in the form of hardware or in the form of software functional modules.

Based on the above embodiment, the embodiment of the present invention further provides a first virtual machine, and the first virtual machine may perform the method provided by the embodiment corresponding to FIG. 3, which may be the same as the first virtual machine 500 shown in FIG. 5.

Referring to FIG. 6, the device where the first virtual machine 600 is located includes at least one processor 601, a memory 602, and a communication interface 603; the at least one processor 601, the memory 602, and the communication interface 603 are all connected by a bus 604;

The memory 602 is configured to store a computer execution instruction;

The at least one processor 601 is configured to execute a computer execution instruction stored by the memory 602, so that the first virtual machine 600 performs data interaction with other devices in the distributed file system through the communication interface 603 to perform the foregoing. The method for storing a file in a distributed file system provided by an embodiment, or causing the first virtual machine 600 to perform data interaction with other devices in the distributed file system through the communication interface 603 to implement a part of the distributed file system or All features.

The at least one processor 601 may include different types of processors 601, or include the same type of processor 601; the processor 601 may be any one of the following: a central processing unit (CPU), an ARM processor , Field Programmable Gate Array (FPGA), dedicated processor and other devices with computational processing capabilities. In an optional implementation manner, the at least one processor 601 may also be integrated into a many-core processor.

The memory 602 may be any one or any combination of the following: a random access memory (RAM), a read only memory (ROM), a non-volatile memory (non-volatile memory). (NVM), Solid State Drives (SSD), mechanical hard disks, disks, disk arrays and other storage media.

The communication interface 603 is used by the first virtual machine 600 to perform data interaction with other devices, such as other devices in a distributed file system. The communication interface 603 may be any one or any combination of the following: a network interface (such as an Ethernet interface), a wireless network card, or the like having a network access function.

The bus 604 can include an address bus, a data bus, a control bus, etc., for ease of representation, Figure 6 shows the bus with a thick line. The bus 604 can be any one or any combination of the following: an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, and an extended industry standard structure ( Extended Industry Standard Architecture (EISA) bus and other devices for wired data transmission.

The embodiment of the present invention provides a name node in a distributed file system, where the distributed file system includes a name node and multiple virtual machines as data nodes, and multiple virtual machines share the same storage area; as shown in FIG. Node 700 includes:

The receiving module 701 is configured to receive a request message that the client requests to write data to be written to the distributed file system;

The sending module 702 is configured to send, to the client, a response message corresponding to the request message received by the receiving module 701, The response message includes an address of the first virtual machine and an address of the second virtual machine, and the response message indicates that the first virtual machine is a virtual machine having the right to write data to the storage area among the plurality of virtual machines, and the second virtual machine is more A virtual machine other than the first virtual machine in the virtual machine.

Optionally, the response message further indicates that the second virtual machine has the right to read the data to be written from the storage area.

Optionally, the response message further includes a write permission identifier of the first virtual machine and a read permission identifier of the second virtual machine, where the write permission identifier is used to specify that the first virtual machine has the right to write the data to be written to the storage area, and the read permission The identifier is used to specify that the second virtual machine has the right to read data to be written from the storage area.

Optionally, the address of the first virtual machine and the address of the second virtual machine in the response message are arranged according to a preset rule, where the preset rule is used to specify that the first virtual machine has the right to write the data to be written to the storage area, and the designated The second virtual machine has the right to read data to be written from the storage area.

Optionally, the sending module 702 is further configured to: when the first virtual machine fails, send the first update information to the client, where the first update information includes an address of the updated first virtual machine, and the first update information specifies multiple Another virtual machine other than the failed first virtual machine in the virtual machine as the updated first virtual machine, the updated first virtual machine has the right to write data to the storage area; and/or when the second virtual machine occurs In the event of a failure, the second update information is sent to the client, the second update information includes the address of the updated second virtual machine, and the second update information specifies another virtual machine other than the plurality of virtual machines as the updated second virtual machine, and is updated. The second virtual machine has the right to read data to be written from the storage area.

The name node 700 provided by the embodiment of the present invention can solve the problem of redundancy of file shares stored in the distributed file system. In addition, when a certain virtual machine in the distributed file system fails, the operation of the name node 700 provided by the embodiment of the present invention can make the failure of the virtual machine not affect the client to read or write the file, thereby improving the System availability.

It should be noted that the name node 700 provided by the embodiment of the present invention can be used to perform the operations performed by the name node in the method for storing files in the distributed file system shown in FIG. 3, and the implementation manner of the name node 700 not explained and described in detail can be referred to. A related description in the method of storing files in the distributed file system shown in FIG.

Based on the above embodiment, the embodiment of the present invention further provides a name node, which can perform the method provided by the embodiment corresponding to FIG. 3, and can be the same as the name node 700 shown in FIG. 7.

Referring to FIG. 8, the name node 800 includes at least one processor 801, a memory 802, and a communication interface 803; the at least one processor 801, the memory 802, and the communication interface 803 are each connected by a bus 804;

The memory 802 is configured to store a computer execution instruction;

The at least one processor 801 is configured to execute a computer execution instruction stored by the memory 802, so that the name node 800 performs data interaction with other devices in the distributed file system through the communication interface 803 to execute the foregoing embodiment. Providing a method of storing files in a distributed file system, or causing the name node 800 to perform data interaction with other devices in the distributed file system through the communication interface 803 to implement some or all of the functions of the distributed file system.

The at least one processor 801 may include different types of processors 801 or include the same type of processor 801; the processor 801 may be any of the following: a CPU, an ARM processor, an FPGA, a dedicated processor, etc. having a processing process Capable device. In an optional implementation manner, the at least one processor 801 can also be integrated into a multi-core processing. Device.

The memory 802 may be any one or any combination of the following: a storage medium such as a RAM, a ROM, an NVM, an SSD, a mechanical hard disk, a magnetic disk, a disk array, or the like.

Communication interface 803 is used by name node 800 to interact with other devices, such as other devices in a distributed file system. The communication interface 803 may be any one or any combination of the following: a network interface (such as an Ethernet interface), a wireless network card, and the like having a network access function.

The bus 804 can include an address bus, a data bus, a control bus, etc., for ease of representation, Figure 8 shows the bus with a thick line. The bus 804 may be any one or any combination of the following: a device for wired data transmission such as an ISA bus, a PCI bus, or an EISA bus.

The embodiment of the present invention provides a client, where the distributed file system of the client includes a name node and multiple virtual machines as data nodes, and multiple virtual machines share the same storage area; as shown in FIG. 9, the client 900 include:

The sending module 901 is configured to send, to the name node, a request message that requests to write data to be written to the distributed file system;

The receiving module 902 is configured to receive a response message corresponding to the request message sent by the name node, where the response message includes an address of the first virtual machine and an address of the second virtual machine, where the response message indicates that the first virtual machine has a plurality of virtual machines. a virtual machine that stores the right to write data in the storage area, and the second virtual machine is a virtual machine other than the first virtual machine among the plurality of virtual machines;

The sending module 901 is further configured to send, to the first virtual machine, the to-be-written data, the address of the second virtual machine, according to the address of the first virtual machine included in the response message received by the receiving module 902, and instruct the first virtual machine to write the to-be-written The data, the metadata for generating or updating the data to be written, and the metadata of the data to be written are transmitted to the second virtual machine according to the address of the second virtual machine included in the response message received by the receiving module 902.

Optionally, the address of the first virtual machine and the address of the second virtual machine included in the response message are arranged according to a preset rule, where the preset rule is used to specify that the first virtual machine has the right to write the data to be written to the storage area, and the specified The second virtual machine has the right to read data to be written from the storage area.

The client 900 provided by the embodiment of the present invention can solve the problem of redundancy of files stored in the distributed file system. In addition, when a certain virtual machine in the distributed file system fails, the operation of the client 900 provided by the embodiment of the present invention can make the failure of the virtual machine not affect the client to read or write files, thereby improving the System availability.

It should be noted that the client 900 provided by the embodiment of the present invention may be used to perform operations performed by a client in a method for storing a file in the distributed file system shown in FIG. 3, and an implementation manner not specifically explained and described by the client 900 may be referred to. A related description in the method of storing files in the distributed file system shown in FIG.

Based on the above embodiment, the embodiment of the present invention further provides a client, where the client can perform the corresponding figure in FIG. 3 . The method provided by the embodiment can be the same as the client 900 shown in FIG.

Referring to FIG. 10, the device where the client 1000 is located includes at least one processor 1001, a memory 1002, and a communication interface 1003; the at least one processor 1001, the memory 1002, and the communication interface 1003 are all connected by a bus 1004;

The memory 1002 is configured to store a computer execution instruction;

The at least one processor 1001 is configured to execute a computer execution instruction stored by the memory 1002, so that the client 1000 performs data interaction with a device in a distributed file system through the communication interface 1003 to perform the foregoing embodiment. A method of storing files in a distributed file system, or causing the client 1000 to perform data interaction with devices in the distributed file system through the communication interface 1003 to implement some or all of the functions of the distributed file system.

The at least one processor 1001 may include different types of processors 1001, or include the same type of processor 1001; the processor 1001 may be any of the following: a CPU, an ARM processor, an FPGA, a dedicated processor, etc. have computational processing Capable device. In an optional implementation manner, the at least one processor 1001 may also be integrated into a many-core processor.

The memory 1002 may be any one or any combination of the following: a storage medium such as a RAM, a ROM, an NVM, an SSD, a mechanical hard disk, a magnetic disk, a disk array, or the like.

Communication interface 1003 is used by client 1000 to perform data interaction with other devices, such as other devices in a distributed file system. The communication interface 1003 may be any one or any combination of the following: a network interface (such as an Ethernet interface), a wireless network card, and the like having a network access function.

The bus 1004 can include an address bus, a data bus, a control bus, etc., for ease of representation, Figure 10 shows the bus with a thick line. The bus 1004 may be any one or any combination of the following: a device for wired data transmission such as an ISA bus, a PCI bus, or an EISA bus.

The embodiment of the present invention provides a second virtual machine in a distributed file system. The distributed file system includes a name node and multiple virtual machines as data nodes, and multiple virtual machines share the same storage area; as shown in FIG. The second virtual machine 1100 includes:

The receiving module 1101 is configured to receive metadata sent by the first virtual machine, where the first virtual machine is a virtual machine that is designated by the name node to have the right to write data to the storage area, and the second virtual machine is The virtual machine other than the first virtual machine in the virtual machine, the metadata is the metadata of the data to be written generated or updated after the first virtual machine writes the data to be written to the storage area.

Optionally, the receiving module 1101 is further configured to: before receiving the metadata sent by the first virtual machine, receive a read permission identifier of the second virtual machine sent by the client, where the read permission identifier is a name node requesting from the client node to the name node The read permission identifier is used to specify that the second virtual machine has the right to read the data to be written from the storage area when the data to be written is written to the distributed file system.

Optionally, the second virtual machine further includes: a processing module 1102, configured to: after the receiving module 1101 receives the metadata sent by the first virtual machine, if the second virtual machine reads the data to be written by using the operating system of the second virtual machine, Metadata generates or updates file information recorded in its own operating system, the file information is used by the operating system to read data to be written from the storage area; or if the second virtual machine reads data to be written, according to metadata from the storage area Read the data to be written.

The second virtual machine 1100 provided by the embodiment of the present invention can solve the problem of redundancy of file shares stored in the distributed file system. In addition, when a certain virtual machine in the distributed file system fails, the operation of the second virtual machine 1100 provided by the embodiment of the present invention may cause the failure of the virtual machine to not affect the client to read or write the file. Increased system availability.

It should be noted that the second virtual machine 1100 provided by the embodiment of the present invention may be used to perform operations performed by the second virtual machine in the method for storing files in the distributed file system shown in FIG. 3, and the second virtual machine 1100 does not explain in detail. For a description of the implementation, reference may be made to the related description in the method for storing files in the distributed file system shown in FIG.

Based on the above embodiment, the embodiment of the present invention further provides a second virtual machine, which may perform the method provided by the embodiment corresponding to FIG. 3, and may be the same as the second virtual machine 1100 shown in FIG.

Referring to FIG. 12, the device where the second virtual machine 1200 is located includes at least one processor 1201, a memory 1202, and a communication interface 1203; the at least one processor 1201, the memory 1202, and the communication interface 1203 are all connected by a bus 1204;

The memory 1202 is configured to store a computer execution instruction;

The at least one processor 1201 is configured to execute a computer execution instruction stored by the memory 1202, so that the second virtual machine 1200 performs data interaction with other devices in the distributed file system through the communication interface 1203 to perform the foregoing. The method for storing a file in a distributed file system provided by an embodiment, or causing the second virtual machine 1200 to perform data interaction with other devices in the distributed file system through the communication interface 1203 to implement a part of the distributed file system or All features.

At least one processor 1201 may include different types of processors 1201, or include the same type of processor 1201; the processor 1201 may be any of the following: CPU, ARM processor, FPGA, dedicated processor, etc. with calculation processing Capable device. In an optional implementation manner, the at least one processor 1201 may also be integrated into a many-core processor.

The memory 1202 may be any one or any combination of the following: a storage medium such as a RAM, a ROM, an NVM, an SSD, a mechanical hard disk, a magnetic disk, a disk array, or the like.

Communication interface 1203 is used by second virtual machine 1200 to perform data interaction with other devices, such as other devices in a distributed file system. The communication interface 1203 may be any one or any combination of the following: a network interface (such as an Ethernet interface), a wireless network card, and the like having a network access function.

The bus 1204 can include an address bus, a data bus, a control bus, etc., for ease of representation, Figure 12 shows the bus with a thick line. The bus 1204 may be any one or any combination of the following: a device for wired data transmission such as an ISA bus, a PCI bus, or an EISA bus.

The embodiment of the present invention provides a distributed file system. As shown in FIG. 13, the distributed file system 1300 includes a first virtual machine 1301, a name node 1302, a client 1303, and a second virtual machine 1304.

The first virtual machine 1301 in the distributed file system 1300 can be used to perform the related operations performed by the first virtual machine in the method for storing files in the distributed file system shown in FIG. 3 , and the specific implementation may be FIG. 5 . The first virtual machine 500 shown or the first virtual machine 600 shown in FIG. 6; the name node 1302 in the distributed file system 1300 can be used to execute the name node in the method for storing files in the distributed file system shown in FIG. The specific implementation of the related operations may be the name node 700 shown in FIG. 7 or the name node 800 shown in FIG. 8; the client 1303 in the distributed file system 1300 may be used to perform the distributed process shown in FIG. File storage in the file system The specific operation performed by the client in the method may be the client 900 shown in FIG. 9 or the client 1000 shown in FIG. 10; the second virtual machine 1304 in the distributed file system 1300 may be used to execute The related operations performed by the second virtual machine in the method for storing files in the distributed file system shown in FIG. 3 may be the second virtual machine 1100 shown in FIG. 11 or the second virtual device shown in FIG. Machine 1200.

In the distributed file system 1300, the data to be written is saved only in a storage area shared by a plurality of virtual machines, which solves the problem of redundancy of files stored in the distributed file system. In addition, when a certain virtual machine in the distributed file system 1300 fails, the client can still perform a write operation or a read operation on the write data by the non-failed virtual machine in the distributed file system 1300, thereby improving the distribution. The availability of a file system.

Those skilled in the art will appreciate that embodiments of the present invention can be provided as a method, system, or computer program product. Accordingly, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or a combination of software and hardware. Moreover, the invention can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) including computer usable program code.

The present invention has been described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (system), and computer program products according to embodiments of the invention. It will be understood that each flow and/or block of the flowchart illustrations and/or FIG. These computer program instructions can be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing device to produce a machine for the execution of instructions for execution by a processor of a computer or other programmable data processing device. Means for implementing the functions specified in one or more of the flow or in a block or blocks of the flow chart.

The computer program instructions can also be stored in a computer readable memory that can direct a computer or other programmable data processing device to operate in a particular manner, such that the instructions stored in the computer readable memory produce an article of manufacture comprising the instruction device. The apparatus implements the functions specified in one or more blocks of a flow or a flow and/or block diagram of the flowchart.

These computer program instructions can also be loaded onto a computer or other programmable data processing device such that a series of operational steps are performed on a computer or other programmable device to produce computer-implemented processing for execution on a computer or other programmable device. The instructions provide steps for implementing the functions specified in one or more of the flow or in a block or blocks of a flow diagram.

Although the preferred embodiment of the invention has been described, it will be apparent to those skilled in the < Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and the modifications and

It is apparent that those skilled in the art can make various modifications and variations to the embodiments of the invention without departing from the spirit and scope of the embodiments of the invention. Thus, it is intended that the present invention cover the modifications and modifications of the embodiments of the invention.

Claims

A method for storing a file in a distributed file system, wherein the distributed file system includes a name node, a plurality of virtual machines as data nodes, and the plurality of virtual machines share the same storage area; :

The first virtual machine receives the data to be written and the address of the second virtual machine sent by the client, where the first virtual machine is specified by the name node in the plurality of virtual machines to have data written to the storage area. a virtual machine of the right, the second virtual machine is a virtual machine other than the first virtual machine among the plurality of virtual machines;

Writing, by the first virtual machine, the data to be written to the storage area, and generating or updating metadata of the data to be written;

The first virtual machine sends the metadata to the second virtual machine according to an address of the second virtual machine.
The method of claim 1, wherein before the first virtual machine writes the data to be written to the storage area, the method further includes:

Receiving, by the first virtual machine, a write permission identifier of the first virtual machine sent by the client, where the write permission identifier is that the name node requests the name node to the distributed file system at the client The write permission identifier is used to specify that the first virtual machine has the right to write the to-be-written data to the storage area when the data to be written is sent to the client.
The method according to claim 1 or 2, wherein the plurality of virtual machines mount the same virtual hard disk provided by the distributed block storage system, and the virtual hard disk includes the storage area.
A method according to any one of claims 1 to 3, characterized in that

If the second virtual machine reads the to-be-written data through its own operating system, the metadata is used by the second virtual machine to generate or update file information recorded in its own operating system, the file information. Used by the operating system to read the data to be written from the storage area; or

And if the second virtual machine reads the to-be-written data, the metadata is used by the second virtual machine to read the to-be-written data from the storage area.
The method according to any one of claims 1 to 4, wherein the second virtual machine is designated by the name node to have the right to read the data to be written from the storage area.
A method for storing a file in a distributed file system, wherein the distributed file system includes a name node, a plurality of virtual machines as data nodes, and the plurality of virtual machines share the same storage area; :

The name node receives a request message that the client requests to write data to be written to the distributed file system;

The name node sends a response message corresponding to the request message to the client, where the response message includes an address of the first virtual machine and an address of the second virtual machine, where the response message indicates that the first virtual machine is One of the plurality of virtual machines having a right to write data to the storage area, the second virtual machine being a virtual machine other than the first virtual machine among the plurality of virtual machines.
The method of claim 6 wherein the response message further indicates that the second virtual machine has permission to read the data to be written from the storage area.
The method according to claim 6 or 7, wherein the response message further comprises a write permission identifier of the first virtual machine and a read permission identifier of the second virtual machine, and the write permission identifier is used for Specify the first The virtual machine has a right to write the data to be written to the storage area, and the read permission identifier is used to specify that the second virtual machine has the right to read the data to be written from the storage area.
The method according to claim 6 or 7, wherein the address of the first virtual machine and the address of the second virtual machine in the response message are arranged according to a preset rule, and the preset rule is used for Designating the first virtual machine to have the right to write the data to be written to the storage area, and to specify that the second virtual machine has the right to read the data to be written from the storage area.
The method according to any one of claims 6 to 9, wherein the plurality of virtual machines mount the same virtual hard disk provided by the distributed block storage system, and the virtual hard disk includes the storage area.
The method of any of claims 6 to 10, further comprising:

When the first virtual machine fails, the name node sends first update information to the client, the first update information includes an updated address of the first virtual machine, and the first update information specifies Depicting another virtual machine other than the first virtual machine that fails in the plurality of virtual machines as the updated first virtual machine, the updated first virtual machine having data written to the storage area Privilege; and/or when the second virtual machine fails, the name node sends second update information to the client, the second update information including an updated address of the second virtual machine, the The second update information specifies another virtual machine other than the plurality of virtual machines as the updated second virtual machine, and the updated second virtual machine has the right to read the to-be-written data from the storage area.
A first virtual machine in a distributed file system, wherein the distributed file system includes a name node, a plurality of virtual machines as data nodes, and the plurality of virtual machines share the same storage area, A virtual machine is a virtual machine in the plurality of virtual machines designated by the name node having the right to write data to the storage area; the first virtual machine includes:

a receiving module, configured to receive data to be written by the client, and an address of the second virtual machine, where the second virtual machine is a virtual machine other than the first virtual machine;

a processing module, configured to write, to the storage area, the to-be-written data received by the receiving module, and generate or update metadata of the to-be-written data;

And a sending module, configured to send, by the processing module, the metadata to generate or update the metadata according to the address of the second virtual machine received by the receiving module.
The first virtual machine according to claim 12, wherein the receiving module is further configured to:

Before the processing module writes the to-be-written data to the storage area, receiving a write permission identifier of the first virtual machine sent by the client, where the write permission identifier is the name node in the When the client requests the name node to write the to-be-written data to the distributed file system, the write permission identifier is used to specify that the first virtual machine has a write to the storage area. Enter the permission to write data.
The first virtual machine according to claim 12 or 13, wherein the plurality of virtual machines mount the same virtual hard disk provided by the distributed block storage system, and the virtual hard disk includes the storage area.
A first virtual machine according to any one of claims 12 to 14, wherein

If the second virtual machine reads the to-be-written data through its own operating system, the metadata is used by the second virtual machine to generate or update file information recorded in its own operating system, the file information. Used by the operating system to read the data to be written from the storage area; or

And if the second virtual machine reads the to-be-written data, the metadata is used by the second virtual machine to read the to-be-written data from the storage area.
The first virtual machine according to any one of claims 12 to 15, wherein the second virtual machine is designated by the name node to have the right to read the data to be written from the storage area.
A name node in a distributed file system, wherein the distributed file system includes the name node, a plurality of virtual machines as data nodes, and the plurality of virtual machines share the same storage area; Nodes include:

a receiving module, configured to receive a request message that the client requests to write data to be written to the distributed file system;

a sending module, configured to send, to the client, a response message corresponding to the request message received by the receiving module, where the response message includes an address of the first virtual machine and an address of the second virtual machine, where the response message indicates The first virtual machine is a virtual machine having the right to write data to the storage area among the plurality of virtual machines, and the second virtual machine is the first virtual machine among the plurality of virtual machines A virtual machine other than the machine.
The name node according to claim 17, wherein said response message further indicates that said second virtual machine has authority to read said data to be written from said storage area.
The name node according to claim 17 or 18, wherein the response message further includes a write permission identifier of the first virtual machine and a read permission identifier of the second virtual machine, where the write permission identifier is used. Dedicating that the first virtual machine has permission to write the to-be-written data to the storage area, the read permission identifier is used to specify that the second virtual machine has read the to-be-written from the storage area Permissions for data.
The name node according to claim 17 or 18, wherein the address of the first virtual machine and the address of the second virtual machine in the response message are arranged according to a preset rule, and the preset rule is used. The first virtual machine is designated to have the right to write the data to be written to the storage area, and the second virtual machine is specified to have the right to read the data to be written from the storage area.
The name node according to any one of claims 17 to 20, wherein the plurality of virtual machines mount the same virtual hard disk provided by the distributed block storage system, and the virtual hard disk includes the storage area.
The name node according to any one of claims 17 to 21, wherein the sending module is further configured to:

Sending, to the client, first update information, where the first update information includes an updated address of the first virtual machine, where the first update information specifies the multiple virtual Another virtual machine other than the first virtual machine that fails in the machine as the updated first virtual machine, the updated first virtual machine has the right to write data to the storage area; and / or

And when the second virtual machine fails, sending second update information to the client, where the second update information includes an updated address of the second virtual machine, and the second update information specifies the multiple virtual Another virtual machine other than the machine serves as the updated second virtual machine, and the updated second virtual machine has the right to read the data to be written from the storage area.