I'm trying to send mails addressed to a subdomain/server sub1.abc.com of our domain abc.com. This domain is handled by a central postfix mail server configured by means of sql. Although the transport table has an entry to relay all mails for sub1.abc.com to that smtp address, main.cf holds a relay_domains entry for sub1.abc.com and dns knows sub1.abc.com and its smtp mx entry postfix keeps looping back to itself.
Edit: I tried the entries for transport, mydestination and relay_domains separately but the result was always the same.
Where can I set this routing entry?