Reports are still being weird. From one user they are missing the report from 3 days last week. Today it showed up but the CSV was blank. I made a copy of the Scheduled Report so I could then manually send it to myself and it came in with data. So not sure what is going on there either.
Logging was not selected in Admin > System Config > Email Settings - so that will help now. Thank you for sharing that tip and the location of the log files.
Output of /var/log/maillog
Mar 17 07:38:28 nagios postfix/pickup[113889]: 1CFC2C05B872: uid=0 from=<root>
Mar 17 07:38:28 nagios postfix/cleanup[98776]: 1CFC2C05B872: message-id=<
[email protected]>
Mar 17 07:38:28 nagios postfix/qmgr[1973]: 1CFC2C05B872: from=<
[email protected]>, size=510780, nrcpt=1 (queue active)
Mar 17 07:38:28 nagios postfix/local[98783]: 1CFC2C05B872: to=<
[email protected]>, orig_to=<root>, relay=local, delay=193, delays=193/0.01/0/0.01, dsn=5.2.2, status=bounced (cannot update mailbox /var/mail/root for user root. error writing message: File too large)
Mar 17 07:38:28 nagios postfix/cleanup[98776]: 23E06C070DFB: message-id=<
[email protected]>
Mar 17 07:38:28 nagios postfix/bounce[98793]: 1CFC2C05B872: sender non-delivery notification: 23E06C070DFB
Mar 17 07:38:28 nagios postfix/qmgr[1973]: 23E06C070DFB: from=<>, size=2742, nrcpt=1 (queue active)
Mar 17 07:38:28 nagios postfix/qmgr[1973]: 1CFC2C05B872: removed
Mar 17 07:38:28 nagios postfix/local[98783]: 23E06C070DFB: to=<
[email protected]>, relay=local, delay=0.02, delays=0/0/0/0.01, dsn=5.2.2, status=bounced (cannot update mailbox /var/mail/root for user root. error writing message: File too large)
Mar 17 07:38:28 nagios postfix/qmgr[1973]: 23E06C070DFB: removed
That just repeats every 5 minutes - there is no other useful data in there that I can see.