Daily Report

[wills]

My Zimbra servers daily report always show postmaster as the top sender. There is no postmaster user and greping /var/log/zimbra.log for postmaster returns zero results.

Where is this user coming from and why is it always the top sender?

[dwmtractor]

That's the user that's sending you all those reports. . . May also be sending a lot of bounces to people/spammers that are trying to hit you with bad email addresses, etc.