[9fans] possible forward loop on new mailserver

[9fans] possible forward loop on new mailserver

[Matthias Teege]

Moin

I want to setup a Plan 9 server to handle mail for mteege.de but I've
got bounces with "failed with error 'possible forward loop'".  I put
"norelay=on" and "ourdomains mteege.de" in /mail/lib/smtpd.conf.  The
MX entry points to the new mailserver.

> @192.168.47.11 mteege.de mx
22664.1: sending to 192.168.47.11/192.168.47.11 mteege.de mx
22664.1: sending to 192.168.47.11/192.168.47.11 mteege.de mx
----------------------------
answer mteege.de                        10 sec          mx   	1 crn.mteege.de
----------------------------

and the name of crn is resolvable

cpu% ndb/query ether `{cat /net/ether0/addr} sys
crn

> @192.168.47.11 crn.mteege.de
22665.1: sending to 192.168.47.11/192.168.47.11 crn.mteege.de ip
22665.1: sending to 192.168.47.11/192.168.47.11 crn.mteege.de ip
22665.1: sending to 192.168.47.11/192.168.47.11 crn.mteege.de ip
----------------------------
answer crn.mteege.de                    10 sec          ip   	192.168.47.11

DNS server and mailserver are on the same machine.

/mail/lib/rewrite looks like this:

...
\l!(.*)					alias		\1
\lmteege\.de!(.*)		alias		\1
\l\.mteege\.de!(.*)		alias		\1
...
# queue all mail for delivery
([^!]*)!(.*) 		| 		"/mail/lib/qmail '\s' 'net!\1'" "'\2'"

I can recieve mail for user@crn.mteege.de but not for user@mteege.de.

The mail bounces with:

The attached mail from 'crn.mteege.de!mtg'
to 'mteege.de!mtg'
failed with error 'possible forward loop'.

What is wrong with this setup?

Many thanks
Matthias

Re: [9fans] possible forward loop on new mailserver

[Robert Raschke]

Matthias Teege wrote:
> /mail/lib/rewrite looks like this:
>
> ...
> \l!(.*)					alias		\1
> \lmteege\.de!(.*)		alias		\1
> \l\.mteege\.de!(.*)		alias		\1
> ...
> # queue all mail for delivery
> ([^!]*)!(.*) 		| 		"/mail/lib/qmail '\s' 'net!\1'" "'\2'"
>
> I can recieve mail for user@crn.mteege.de but not for user@mteege.de.
>

My rewrite looks similar, but subtly different:

# your local names
\l!(.*)					alias		\1
\l\.tombob\.com!(.*)		alias		\1
tombob\.com!(.*)		alias		\1
...
# queue all mail for delivery
([^!]*)!(.*) 		| 		"/mail/lib/qmail '\s' 'tcp!\1'" "'\1!\2'"

If I remember correctly (it's been over five years), I explicitly
added the "tombob\.com!(.*)" pattern.  Also, the qmail invocation in
my rewrite has a bang (not sure what the significance of that is).

Robby

--
r.raschke@t-o-m-b-o-b.com

Re: [9fans] possible forward loop on new mailserver

[geoff]

Try

	mail '-#d' crn.mteege.de!mtg

and see how the addresses are being rewritten.  Also watch the tail of
/sys/log/mail and /sys/log/smtp.  I suspect that a plain user name
like `mtg' is getting rewritten, possibly by upas/aliasmail, into an
address that causes upas to send the message to mteege.de via smtp and
this is being caught after 32 iterations.