Author: Patrick Starrenburg Date: To: exim-users Subject: [Exim] Re: Newbie question about verifying recipient addresses.
"Mark Boyd" <mboyd@???> writes:
> ...From exim I want to verify
> the recipient addresses, and if they're not valid reject the message at
> the "rcpt to:..." level rather than forwarding it to my Exchange server
> and having it generate an "Unknown address message". To implement this
> scheme I've tried various combinations of the receiver_verify_addresses
> and sender_reject_recipients options but neither one seems to get
> activated on the inbound SMTP messages. I would highly appreciate any
> insight into what is most likely a configuration issue.
This has been mentioned some time past on the list (Exim acting as a proper
mail server protecting Exchange) and the suggestion then was to use LDAP
lookups to verify valid Exchange server mailboxes. You can find the messages
on the list archive.
I also am starting project looking at this as there is *no way* I would connect
an Exchange box to the Internet, and I want to bounce emails at the (Exim) mail
boundary for many reasons - spam, rogue domains & netblocks, attachments - at
the point of RCPT/DATA communication. We will be looking at direct LDAP, if you
are running W2K AD/Exchange 2000 then you can query LDAP in AD or if you have
Exchange 5.5 (hope you don't have 5.0) then (according to past messages) you
can query LDAP direct on Exchange server. One other thing we were considering
was regularly exporting mail addresses to PostgreSQL database and doing
lookups against that. Reason being that we are planning to use PostgreSQL to
maintain lists for blacklists etc. and to build easy to use front-end to
PostgreSQL database. Obvious downside to this is you have two data sources
which is not ideal.
