[Apologies in advance for the less than complete information below;
hoping someone may have an idea of what's happening anyway]
I'm having a problem where messages are accepted but then seem to
generate a mail forwarding loop. It seems to happen a lot with mail from
a particular spammer.
The To: header in the raw email as viewed in postcat looks like this:
To: f...@example.edu <f...@example.edu>
(where f...@example.edu is a valid address which works in other cases;
the unbracketed address isn't quoted, though in my tests, Postfix seems
to fix this by quoting the bare address, so I'm not sure why that's not
the case in the queue file).
Postfix accepts the mail initially, but then the mail gets rejected
(and, since the sender domain resolves to a host which has no mail
server listening, the DSN sits in our queues for days).
Nov 27 05:05:47 hostname postfix/smtpd[32160]: 0C18B32807B:
client=ajaxkottely.info[93.115.135.15]
Nov 27 05:05:47 hostname postfix/cleanup[32525]: 0C18B32807B:
message-id=<673371cd-8f1f-0dc8-cd7d-a4571d4c1...@ajaxkottely.info>
Nov 27 05:05:47 hostname postfix/qmgr[7633]: 0C18B32807B:
from=<medicare.enrollm...@ajaxkottely.info>, size=8323, nrcpt=1 (queue active)
Nov 27 05:05:47 hostname postfix/lmtp[31222]: DD086328056:
to=<f...@example.edu>, relay=127.0.0.1[127.0.0.1]:33325, conn_use=2, delay=9.4,
delays=1.8/0/0/7.6, dsn=2.0.0, status=sent (250 2.0.0 from
MTA([127.0.0.1]:33326): 250 2.0.0 Ok: queued as 0C18B32807B)
Nov 27 05:05:47 hostname postfix/local[32177]: 0C18B32807B:
to=<f...@example.edu>, relay=local, delay=0.04, delays=0.02/0.02/0/0.01,
dsn=5.4.6, status=bounced (mail forwarding loop for f...@example.edu)
Unfortunately, I can't post full postconf -n output here (see snippets
below), but suffice it to say that I'm confident that mail to
f...@example.edu works under most conditions. Is there anything I can do
to figure out the cause of this?
Users are defined in LDAP, and in this case, example.edu is *not* a
virtual domain. localhost:33326 is the return from amavis.
mail_version = 2.3.3
alias_maps = proxy:ldap:acct_alias_ldap,
proxy:ldap:other_alias_ldap,
hash:/etc/postfix/config/aliases
virtual_alias_maps = hash:/etc/postfix/config/virtusertable
I will try adding the sending host in question to $debug_peer_list to
see if I get any more information. I am happy to provide other debugging
information within reason if it's possible.
w
