We have a postfix system that accepts mail from our internal network. It scans
emails for virusses and spam before delivering it.
It's listening on port 26 and so far everything works.
Last night one of our users's mailbox got hacked and they tried to send a lot
of spam emails. Most of it got
Hi Wietse,
Thanks for clearing that out. I read the first part of the manual and thought
it would block if postfix is not the final destination but I didn't really
understand the AND part of the sentence but now I do. So it's not the option I
need. My bad! ;)
Now, to get back to your suggestio
Wietse, you're the best!
Thank you very very much :)
- Original Message -
From: "Wietse Venema"
To: "postfix-users"
Sent: Monday, May 13, 2019 4:46:57 PM
Subject: Re: Postfix as an outgoing spam filter. How to block email for unknown
senders in local network?
Wietse Venema:
> sander
Hi,
I have:
# postconf |grep unverified_recipient_reject_
unverified_recipient_reject_code = 550
unverified_recipient_reject_reason = Unknown recipient address
Yet, postfix is still rejecting with:
May 20 08:38:27 mx10 postfix/smtpd[8934]: NOQUEUE: reject: RCPT from
host.com[x.x.x.x]: 450 4.1.
Thanks. I modified the internal server to reply with 550 instead of 450 and now
postfix is using 550 too :-)
Other question:
Can I somehow have postfix only verify recipient addresses for internal
mailservers?
Right now it's doing this for outgoing emails too, verifying the recipient
address,
