Topic: Using Koozali as a backup E-mail server

[Arnie]

Hello,

Until recently, I have used a backup MX service provided by my ISP to process mail in the event my Koozali server was offline (WAN outage, power failure etc). My ISP has informed me that they are discontinuing this service so I need to implement another solution.

Would it be possible to set up another Koozali server as a VPS and have it as a backup MX relay? I would assume the setup would be to copy the user accounts to the backup MX server and then get the server to forward all stored mail to my main server when it becomes available but that is the bit I can't figure out. How do I tell the backup Koozali box that it needs to forward all mail to the main one.

Secondarily, how would I configure the second Koozali server to modify things like retention duration and retries?

Thanks.

[TerryF]

Worth a read - https://wiki.koozali.org/Mxbackup

[Arnie]

Thank you, TerryF. EXACTLY what I needed!

[ReetP]

Please note that there is no guarantee that the contrib works in any way shape or form. The contrib is STRICTLY Alpha only. I just imported, and tidied a few obvious bits.

Please follow up on the bug with any issues. I am happy to try and fix anything but need some feedback.

https://bugs.koozali.org/show_bug.cgi?id=12162

I would assume the setup would be to copy the user accounts to the backup MX server and then get the server to forward all stored mail to my main server when it becomes available but that is the bit I can't figure out.

No you do not need to copy user accounts across. IIRC an MX server should hold ALL mail for the domain. It does not differentiate between accounts - that is the job for the actual mail server. An MX server is really just a "store and forward when possible" server.

How do I tell the backup Koozali box that it needs to forward all mail to the main one.

It should do that automatically with the contrib which adds mail settings, but I have no idea if it works correctly!

The MX server should periodically poll the receiving server and forward when it is available.

I'd like to implement one myself, but time has prevented me spending much on it. More than happy to hear about your efforts. You really need to read some of the qmail documentation.

[Arnie]

Thanks ReetP for the info. With the unknown usability of the MXBackup contrib, I went another way. I found the following:

https://www.linuxbabe.com/mail-server/how-to-set-up-a-backup-email-server-postfix-ubuntu

I set up a bare-bones Ubuntu server on a VPS and configured Postfix as described in the link and it all works perfectly.
After hardening the VPS with UFW and ensuring only port 25 is open, I'm happy with the result.

[ReetP]

That's sad, and why items do not get fixed here

It would probably have been easier to get fixed on SME.

Note for many reasons already discussed elsewhere here the certification part is largely irrelevant - you cannot guarantee an end to end encrypted connection so your mail can flow through unencrypted servers outside your control - so a lot complexity with zero gain.

Also unless you use PGP it's a really good reason not to use email for secure communications