Dovecot is not working

Question

I'm having a server. The server information I've given below.

Linux host.com 2.6.32-531.29.2.lve1.3.11.1.el6.x86_64 #1 SMP Thu Dec 18 06:49:17 EST 2014 x86_64 x86_64 x86_64 GNU/Linux

When I was trying to restart Dovecot IMAP and POP. It got failed and showing following error.

Jul 23 01:30:41 platinum dovecot: imap-login: Fatal: master: service(imap-login): child 747903 returned error 127
Jul 23 01:30:41 platinum dovecot: pop3-login: Fatal: master: service(pop3-login): child 747902 returned error 127
Jul 23 01:30:40 platinum dovecot: master: Error: service(imap-login): command startup failed, throttling for 2 secs
Jul 23 01:30:40 platinum dovecot: master: Error: service(pop3-login): command startup failed, throttling for 2 secs
Jul 23 01:30:39 platinum dovecot: master: Warning: /selinux is no longer mounted. See http://wiki2.dovecot.org/Mountpoints

I've read some manual, tried to ignore this mounted file. However it is still not working. May i know how I can solve this issue ?

After manual restart following is logs

Jul 23 02:19:43 platinum dovecot: master: Error: service(imap-login): command startup failed, throttling for 2 secs
Jul 23 02:19:44 platinum dovecot: pop3-login: Fatal: master: service(pop3-login): child 805429 returned error 127
Jul 23 02:19:44 platinum dovecot: imap-login: Fatal: master: service(imap-login): child 805430 returned error 127
Jul 23 02:20:11 platinum dovecot: imap-login: Error: dovecot/imap-login: error while loading shared libraries: librt.so.1: failed to map segment from shared object: Cannot allocate memory
Jul 23 02:20:11 platinum dovecot: imap-login: Error: dovecot/imap-login: error while loading shared libraries: librt.so.1: failed to map segment from shared object: Cannot allocate memory
Jul 23 02:20:11 platinum dovecot: imap-login: Fatal: master: service(imap-login): child 806007 returned error 127
Jul 23 02:20:11 platinum dovecot: master: Error: service(imap-login): command startup failed, throttling for 4 secs
Jul 23 02:21:24 platinum dovecot: imap-login: Error: dovecot/imap-login: error while loading shared libraries: librt.so.1: failed to map segment from shared object: Cannot allocate memory
Jul 23 02:21:24 platinum dovecot: master: Error: service(imap-login): command startup failed, throttling for 8 secs
Jul 23 02:21:24 platinum dovecot: imap-login: Fatal: master: service(imap-login): child 807199 returned error 127

Even if from the following solution, I got the same error. Update :

Jul 23 02:42:08 platinum dovecot: master: Error: service(imap-login): command startup failed, throttling for 2 secs
Jul 23 02:42:08 platinum dovecot: master: Error: service(pop3-login): command startup failed, throttling for 2 secs
Jul 23 02:42:05 platinum dovecot: master: Warning: /selinux is no longer mounted. See http://wiki2.dovecot.org/Mountpoints
Jul 23 02:42:05 platinum dovecot: master: Warning: /var/named/chroot/etc/named.conf is no longer mounted. See http://wiki2.dovecot.org/Mountpoints
Jul 23 02:42:05 platinum dovecot: master: Warning: /var/named/chroot/var/named is no longer mounted. See http://wiki2.dovecot.org/Mountpoints

After un-mounting the /selinux I found following errors.

Jul 23 03:00:45 platinum dovecot: pop3-login: Fatal: master: service(pop3-login): child 847454 returned error 127
Jul 23 03:00:45 platinum dovecot: imap-login: Fatal: master: service(imap-login): child 847450 returned error 127
Jul 23 03:00:45 platinum dovecot: pop3-login: Fatal: master: service(pop3-login): child 847449 returned error 127
Jul 23 03:00:45 platinum dovecot: pop3-login: Error: dovecot/pop3-login: error while loading shared libraries: librt.so.1: failed to map segment from shared object: Cannot allocate memory
Jul 23 03:00:45 platinum dovecot: pop3-login: Error: dovecot/pop3-login: error while loading shared libraries: librt.so.1: failed to map segment from shared object: Cannot allocate memory

Solution

From the information you provided, I'm assuming that you are most probably running RHEL 6 or CentOS 6.

Perhaps you should try starting the dovecot service manually first and post the log again.

--Update

Ok. These steps should fix the problem.

1. Edit the file using the command vi /etc/dovecot.conf

2. Find the line which has login_process_size

3. Uncomment it and modify it to login_process_size = 64

4. Save the file and start the service with service dovecot stop and service dovecot start

I found this solution from here.

Comments

[roaima]

Whst distro is this on?

[SSK]

Im using CentOS

[sebix]

And there is free memory available for dovecot?

[SSK]

Okay Issue resolved. I've increased the size. Thank you all :)

[SSK]

No Didn't started any service manually.

[HawkEye]

Try starting the dovecot service using service dovecot start and later post the output of tail /var/log/upstart/dovecot.log

[SSK]

I've updated the Question.

[SSK]

Updated please check

[SSK]

Jul 23 02:57:40 platinum dovecot: imap-login: Fatal: master: service(imap-login): child 844203 returned error 127 Jul 23 02:57:40 platinum dovecot: imap-login: Fatal: master: service(imap-login): child 844207 returned error 127 Jul 23 02:57:40 platinum dovecot: pop3-login: Fatal: master: service(pop3-login): child 844202 returned error 127 Jul 23 02:57:39 platinum dovecot: master: Error: service(imap-login): command startup failed, throttling for 2 secs Jul 23 02:57:39 platinum dovecot: master: Error: service(pop3-login): command startup failed, throttling for 2 secs

[Kelzier]

Have you tried to disable SELinux?

[SSK]

Nop. I can't Disable SELinux.

[Kelzier]

If you can't disable SELinux, you should set up more verbose dovecot logs. Set mail_debug = yes in /etc/dovecot/conf.d/10-logging.conf.