[cobalt-users] alias database /etc/mail/aliases autorebuilt by root - User unknown problem

[Rishi Gangoly - User Groups <usergroups@xxxxxxxxxxxxxxxxxxx>]

Hi

For the past 1 year now, I've been receiving a "User unknown" error for valid 
users on my Cobalt RaQ4 system.

I finally think I've understood why. Whenever I add or remove a user into the 
system, the /etc/mail/aliases file gets autorebuilt by root. If a mail at 
that point of time is being sent to the system, it generates a User unknown 
error and bounces these messages.

See from logs below...

Does anyone know if there is a reliable solution to this problem?

I was thinking of stopping sendmail when adding/removing users. After it's 
done, then I will start sendmail again. However, during this time the system 
will not accept email for all the domains. 

But would they get a permanent fatal error or a non-fatal deferred error?

LOGS
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Apr 19 17:58:44 domain sendmail[27712]: alias database /etc/mail/aliases 
autorebuilt by root
Apr 19 17:58:44 domain sendmail[27712]: h3JCShA27712: <narayan@xxxxxxxxx>... 
User unknown
Apr 19 19:14:07 domain sendmail[3418]: alias database /etc/mail/aliases 
autorebuilt by root
Apr 19 19:14:15 domain sendmail[3463]: h3JDiEf03463: 
<vikram@xxxxxxxxxxxxxxxxxxx>... User unknown
Apr 19 20:00:25 domain sendmail[8269]: alias database /etc/mail/aliases 
autorebuilt by root
Apr 19 20:00:25 domain sendmail[8269]: h3JETvf08192: to=<ashish@xxxxxxxxxxx>, 
delay=00:00:27, mailer=local, pri=122162, dsn=5.1.1, stat=User unknown
Apr 19 20:00:25 domain sendmail[8269]: h3JETvf08192: h3JEUO708269: DSN: User 
unknown
Apr 19 20:00:28 domain sendmail[8278]: h3JEUIf08253: 
to=<anil@xxxxxxxxxxxxxxxxxxx>, delay=00:00:09, mailer=local, pri=151474, 
dsn=5.1.1, stat=User unknown
Apr 19 20:00:29 domain sendmail[8278]: h3JEUIf08253: h3JEUSi08278: DSN: User 
unknown
Apr 19 14:41:31 domain sendmail[4503]: alias database /etc/mail/aliases 
autorebuilt by root
Apr 19 14:41:31 domain sendmail[4503]: h3J9BAH04447: to=<neeraj@xxxxxxxxxxx>, 
delay=00:00:21, mailer=local, pri=120528, dsn=5.1.1, stat=User unknown
Apr 19 14:41:32 domain sendmail[4503]: h3J9BAH04447: h3J9BUm04503: DSN: User 
unknown
Apr 19 14:41:39 domain sendmail[4520]: h3J9BbH04520: <sanjay@xxxxxxxxxx>... 
User unknown
Apr 19 14:41:48 domain sendmail[4554]: h3J9BYH04512: to=<rajesh@xxxxxxxxxxx>, 
delay=00:00:14, mailer=local, pri=243211, dsn=5.1.1, stat=User unknown
Apr 19 14:41:48 domain sendmail[4554]: h3J9BYH04512: to=<savio@xxxxxxxxxxx>, 
delay=00:00:14, mailer=local, pri=243211, dsn=5.1.1, stat=User unknown
Apr 19 14:41:55 domain sendmail[4554]: h3J9BYH04512: to=<nadar@xxxxxxxxxxx>, 
delay=00:00:21, mailer=local, pri=243211, dsn=5.1.1, stat=User unknown
Apr 19 14:41:55 domain sendmail[4554]: h3J9BYH04512: h3J9BlN04554: postmaster 
notify: User unknown
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