After latest update no working mailserver

[timmetje]

Hi All,

First post (never had issues before) but now with latest update my mailserver isnt working anymore.
First some info:
Virtualization: vmware
Operating System: CentOS Linux 7 (Core)
CPE OS Name: cpe:/o:centos:centos:7
Kernel: Linux 3.10.0-514.26.2.el7.x86_64
Architecture: x86-64

mailserver running: ESMTP Postfix
POP: Dovecot

Before the updates i always do a snapshot. So i revert at this moment.

Problems:
When i use the command: yum update i have this packages waiting for me:

Install 11 Packages (+35 Dependent packages)
Upgrade 227 Packages
Remove 1 Package

Total download size: 259 M

After the update / reboot i cannot send mail and receive them.

nmap shows me port 25 is running
I hope some one can tell me what the differents is after the upgrade so i can look in the right direction.

I hope someone can help.
And yes a log from maillog /messages should make it alot easy but i update tonight again because now i need the mailserver.
With this post i hope someone got this problem to and got a solution.

Regards,

Tim

[TrevorH]

There's no information here that would let anyone debug this. You'll need to look at the logs and copy them off somewhere to preserve them before you revert to your snapshot next time.

[timmetje]

There's no information here that would let anyone debug this. You'll need to look at the logs and copy them off somewhere to preserve them before you revert to your snapshot next time.

oke thx. I could try ofcourse but indeed i make logs after the update. I had little hope someone faced this problem before / know some issues with 7.4.

I try to troubleshoot first then.

thx.

[timmetje]

Solution for postfix / exim users:

Centos 7.4 puts sendmail for default smtp server?

Solution:

yum autoremove sendmail (or exim)

chkconfig postfix on
or
chkconfig exim on

reboot and test with telnet localhost 25