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How can I configure the default mail sender properties on a debian server (with a mail transport agent of exim4, if it matters)?


I'm running a server (debian 5, the mta is exim4) hosted by rackspace. Rackspace mail uses outgoing sender address authentication, such that I can only send email from vetted "from" addresses.

Sending as, say, a local user results in a rejection:

  SMTP<< 550 5.1.0 <>: 
Sender address rejected: User unknown in relay recipient table
  SMTP<< 554 5.5.1 Error: no valid recipients
  ** R=smarthost T=remote_smtp_smarthost: 
SMTP error from remote mail server after RCPT TO:<>:
 host [xxxxxxx]: 550 5.1.0 <>: 
Sender address rejected: User unknown in relay recipient table

Problem is, I'm using a really simple app (logcheck, ) in an attempt to simply email out logs to myself. Logcheck doesn't have any built-in configuration for where the mail get sent from.

So whatever is the default is getting set as, by the system, I need to configure it to make sure it's a vetted address. Where do I start?

share|improve this question
Part of what ended up causing my problem is that only authorized users are allowed to send out via my rackspace smarthost, so I had to make sure that whoever the default send-out user was, the /etc/email-addresses alias mentioned below by coredump handled that fake user, and re-aliased it to a real user who the smarthost would truly accept. In my case it was being sent out as because the www-data user was in control of the php scripts that were trying to send email. Alias www-data to and they started being delivered. – Kzqai Feb 23 '15 at 3:30
up vote 3 down vote accepted

There's a /etc/email-addresses that associates outgoing email addresses with local user accounts (it's part of the default rewrite config of Debian's Exim). I think this is the better solution for your problem.

Also, during a dpkg-reconfigure exim4-config there's an option Hide local mail name in outgoing name, see if it can help you.

share|improve this answer
Thanks, I'll check into that. – Kzqai Mar 23 '11 at 4:11
Using /etc/email-addresses definitely ended up solving my problem, gracias. – Kzqai May 23 '11 at 16:21

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