On 1/30/2011 3:57 PM, Dominik Schulz wrote:
Hi,
I'm currently planning to migrate an Exim mailserver to Postfix due to
performance issues and security concerns.
The only remaining open issue is something I'd like to call selective relaying
- please provide a more apt name if there is one.
The Exim mailserver is configured to handle several virtual domains. If a
recipient is not found in the virtual table, before rejecting this recipient,
exim checks an MS Exchange mailserver via SMTP if the it would accept this
recipient. If it does the mail is accepted and relayed to the Exchange server.
If it does not the mail is rejected.
My question is: How can configure postfix to allow the same kind of selective
relaying?
At the moment I don't think that I could use relay maps, because the as far as
I understood it, they work with a static list of recipients. Futhermore I
don't have LDAP access to the Exchange server - only SMTP.
I welcome simple or complex solutions as long as they come as close as
possible to the existing setup. However I can't use internal Domains which are
rewritten to the outside.
Maybe this helps?
http://www.postfix.org/ADDRESS_VERIFICATION_README.html#recipient
IIRC the examples in that document show verifying recipients
for all accepted domains. It's also possible to verify
recipients for a single target domain by using a
check_recipient_access map.
-- Noel Jones
