How to route mail in Postifix based on recipient address

Question

I have built a Spam filter based on this RECIPE

Since then my requirements have changed and would like to know how to route mail in Postfix based on the recipient email address. Some users now belong to a new domain and are hosted on another mail server but I do not want to lose mail that is sent to their old address.

So if I receive:

• [email protected] it forward to the old mail server with the same address
• [email protected] it forward to [email protected]
• [email protected] it drops without NDR because it is not listed in "relay_recipient_maps"

When I tried to simply add the following to /etc/postfix/virtual the test message seemed to just get lost somewhere. I have no clue where it went or how to check where it went...

[email protected] [email protected]

Many thanks for any pointers.

Answer 1

You can use transport_maps

relay_domains = olddomain.com, newdomain.com
transport_maps = /etc/postfix/relay_maps
recipient_canonical_maps = hash:/etc/postfix/recipient_canonical

/etc/postfix/relay_maps

[email protected] smtp:[ip.of.local.exchange]
[email protected] smtp:mx.newdomain.com
[email protected] no-reply

/etc/aliases

no-reply: /dev/null

/etc/postfix/recipient_canonical

[email protected] [email protected]

Note: you must create local user no-reply