diff --git a/Dockerfile b/Dockerfile
index 5395bf5..d80fc6b 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,5 +1,4 @@
-From ubuntu:trusty
-MAINTAINER Elliott Ye
+FROM ubuntu:focal
 
 # Set noninteractive mode for apt-get
 ENV DEBIAN_FRONTEND noninteractive
@@ -9,10 +8,10 @@ RUN apt-get update
 
 # Start editing
 # Install package here for cache
-RUN apt-get -y install supervisor postfix sasl2-bin opendkim opendkim-tools
+RUN apt-get -y install postfix sasl2-bin opendkim opendkim-tools
 
 # Add files
 ADD assets/install.sh /opt/install.sh
 
 # Run
-CMD /opt/install.sh;/usr/bin/supervisord -c /etc/supervisor/supervisord.conf
+CMD /opt/install.sh;/opt/postfix.sh
\ No newline at end of file
diff --git a/assets/install.sh b/assets/install.sh
index 0b2aaff..155a609 100755
--- a/assets/install.sh
+++ b/assets/install.sh
@@ -1,32 +1,17 @@
 #!/bin/bash
 
-#judgement
-if [[ -a /etc/supervisor/conf.d/supervisord.conf ]]; then
-  exit 0
-fi
-
-#supervisor
-cat > /etc/supervisor/conf.d/supervisord.conf <<EOF
-[supervisord]
-nodaemon=true
-
-[program:postfix]
-command=/opt/postfix.sh
-
-[program:rsyslog]
-command=/usr/sbin/rsyslogd -n -c3
-EOF
-
 ############
 #  postfix
 ############
 cat >> /opt/postfix.sh <<EOF
 #!/bin/bash
-service postfix start
-tail -f /var/log/mail.log
+postfix start-fg
 EOF
+
 chmod +x /opt/postfix.sh
 postconf -e myhostname=$maildomain
+postconf -e maillog_file=/dev/stdout
+postconf -e mydestination="localhost.localdomain,localhost"
 postconf -F '*/*/chroot = n'
 
 ############
@@ -127,4 +112,4 @@ cat >> /etc/opendkim/SigningTable <<EOF
 *@$maildomain mail._domainkey.$maildomain
 EOF
 chown opendkim:opendkim $(find /etc/opendkim/domainkeys -iname *.private)
-chmod 400 $(find /etc/opendkim/domainkeys -iname *.private)
\ No newline at end of file
+chmod 400 $(find /etc/opendkim/domainkeys -iname *.private)
diff --git a/build.sh b/build.sh
index d7b5420..e8245ad 100755
--- a/build.sh
+++ b/build.sh
@@ -1,3 +1,2 @@
 #!/bin/bash
-
-docker build -t catatnight/postfix .
\ No newline at end of file
+docker build -t catatnight/postfix .