1 (edited by sunnis 2011-07-22 22:49:02)

Topic: Fallback mail server

it is possible to forward mail that have this error to another mailserver?

"Sender address rejected: User unknown in virtual mailbox table;"

What were looking for is something like this...

email --> iredmail server --> if there *is* an account, then deliver locally
email --> iredmail server--> if there's no account, then forward to another smtp.

I have tried with postfix fallback_transport but i cant get it to work.


Re: Fallback mail server

It does possible.
What you need is a catch-all account, you can forward all emails delivered to non-exist accounts to an email address (internal or external).

Please refer to below wiki tutorials to create a catch-all account manually:
- For OpenLDAP backend: http://www.iredmail.org/wiki/index.php? … /Catch-all
- For MySQL backend: http://www.iredmail.org/wiki/index.php? … /Catch-all

If you have iRedAdmin-Pro (web-based admin panel) running, you can easily configure it in domain profile page:


Does my reply help a little? How about buying me a cup of coffee ($5) as an encouragement?

buy me a cup of coffee

3 (edited by sunnis 2011-07-23 02:13:17)

Re: Fallback mail server

I do not want to forward every failed mail to one singel email adress.

The problem we have is that we have a old mailserver that have 2 domains and hosting over 10k accounts. Around 90-95% of the accounts are not used today. Instead of migrating each account to our new iredmail server, we have a signup where they can re-register their address on the new iredmail server. The new and the old server will coexist in a few months so that users have time to re-register. The problem is that if I  change the mx records on the domain it will no longer go to the old server, I want these to co-exist with the same @domain.

In somehow I want the old server work like a fallback if the user doesn't exist on the new iredmail server.

email to user1@domain.com -> iredmail -> if exist then deliver locally else relay message to user1@domain.com to the old mailserver.