Symptoms
All inbound emails are deferred by Postfix. The following messages appear in /var/log/maillog
.
status=deferred (Unable to read message content )
...
postfix-local: cannot create temporary file - (30) Read-only file system
Cause
Postfix is installed from OS vendor repository:
# rpm -qi postfix | grep Packager
Packager : CentOS Buildsys bugs@centos.org
Resolution
-
Connect to the Plesk server via SSH.
-
Open the file
/usr/lib/systemd/system/postfix.service
in a text editor. In this example, we are using the vi editor:# vi /usr/lib/systemd/system/postfix.service
-
Comment the following lines out by placing a # (hash) character at the beginning of the line:
#PrivateTmp=true
#CapabilityBoundingSet=~ CAP_NET_ADMIN CAP_SYS_ADMIN CAP_SYS_BOOT CAP_SYS_MODULE
#ProtectSystem=true
#PrivateDevices=true -
Save the changes and close the file.
-
Reload systemd unit file:
# systemctl daemon-reload
-
Restart the Postfix service:
# systemctl restart postfix