Sender address domains get replaced incorrectly

[Monti]

Hi,

I got a strange issue now, that took me quite some time to figure out:

Let's assume our server's name is aaa.com
There are several other domains bbb.com, ccc.com ddd.com ... (no xxx.com for sure

Now, sending a message to an external mail account, for some users, the sender address' domain is always replaced by aaa.com

If a user has the address foo.bar@ccc.com, Replys will be sent to foo.bar@aaa.com because this is shown as sender. Even, if foo.bar@aaa.com is not at all set up in any of the accounts.

For clarification:
Mr. Foo Bar has 5 addresses set up in SAC:

foo.bar@aaa.com
master.foo.bar@bbb.com
qwer.asdf.master@ccc.com
foo.bar.man@ddd.com
qwer.asdf@eee.com
foo.bar@fff.com

So, you can say that if bbb.com, ddd.com or fff.com are at the top as default, it works, sender will be foo.bar.man@ddd.com
Now, if ccc.com or eee.com are at the top, the sender might be qwer.asdf.master@aaa.com or qwer.asdf@aaa.com

Generally, it looks like some domains are ALWAYS converted into aaa.com - if the address exists or not.

Of course, all domains are listed in the localdomains list.

Can anyone give me a hint, where this isse might be cause?
Where can I manually check, which domains really are set up or if some domains are somehow set to be "always replaced"?

I am out of ideas...

Thanks for your help!!!

[ssiekmann]

Hi,

you need to show us the output of omsearch -m @all-attr@ -e cn=Username of a user that has the issue - you were not saying all users have the problem, so I'd like to look at that first.

Other than that, I would like to see /etc/mail/local-host-names.

Another possibility might be that you have turned on masquerading for this domain, sendmail.cf would be the place to check that.

Gruss,

Sascha.

[Monti]

Hi,

thanks for the hints, the problem is solved.

Reasons was, that a couple of domains (those with problems) were entered as aliases in /etc/mail/local-host-names. Those were always replaced by the "main" name.
So, this was the place which caused those domains to be "identical" or at least to be considered as identical.

Removed them and restarted sendmail - DONE!

Ein dickes Dankeschön

Monti