Help My Mail In the Box server keeps randomly failing to send and receive mail

If anyone could help, I would much appreciate it.

After one year of the mail server running without any issue all of a sudden this past month the system randomly decided to spot sending and receive mail. the website works fine, but then you get a server connection error when sending mail, and everyone sending mail to the service receives a message expired warming the mail server hasnt responded.

The only way I have been able to fix this is by restoring from last know good backup, then after a week or so it breaks again. Non of the service routines seem to fix the issue ether, nor any upgrade function. The system remains broken until the entire thing is wiped clean and reloaded with a full backup, to only fail again a week later.

OS is Ubuntu 22.04


I’d be happy to help. The best time to troubleshoot would be when it breaks again, unfortunately.

I’ll send you a PM with some questions (hostname, provider, etc.).

Self Hosted. It’s running as a VM inside a Proxmox hypervisor. The backups are full image backups through the hypervisor. Miab v60. I’m thinking that it might be Ubuntu 22.04 updates breaking it. I think the issues is related to postfix and IMAP. everything else works when it fails, but STMP and IMAP. Any reinstall of MIAB changes nothing. The only way to fix it is the revert a snapshot or full backup. I’ve since disabled all ubuntu repos and update functions. Well see what happens.

Ahh, yeah. Sorry but I can’t help you there.

Best of luck.

Is its not uncommon that Ubuntu LTS updates will break various functions and features of MIAB?

It is very very uncommon. I do not think that I have ever experienced it tbh.

There does seem to be an issue with duplicity that this is now happening with, but I still haven’t faced issues.

Hmmm… its the only link I can think of…

Failed again, the only thing that I can say is that when I go to send an email It just says failed to connect to server. Everything else works fine, I even ran upgrade, but still has an issues sending and receiving. Munin shows zero warning or errors. I cannot find anything wrong, but still everytime I restore this machine it randomly breaks, and cannot sent or receive emails. Its completely random, could be a few days, weeks, or one day later.

Update: looks like there is a problem in dovecot.

Also found a list of I/O Read Write Issues in the logs. I think its possible there is data corruption going on with this Virtual machine and its Disk configuration.

If you’re running MIAB v60 you might be hit by this issue where changing the password in Roundcube caused postfix to stop delivering email. See e.g. Changing the password on Roundcube WILL make Postfix unable to receive mail · Issue #85 · ddavness/power-mailinabox · GitHub (not the mail in a box issue tracker, but the issue is also applicable to miab). It is fixed in V62.

I Believe that was the Fix my friend. after I restored my MIAB from a known good backup image, I then immediately upgraded it from V60 - V64. It has been running without any trouble since, it is also a bit more snappier as well.