 backups?
Are you running scheduled backups? (zmschedulebackup with no arguments will dump the backup schedule). Backups put accounts into maintenance mode, which will cause a temporary delivery failure.
Is there anything else in the logs around this time? What about /opt/zimbra/log/zimbra.log or /opt/zimbra/tomcat/logs/catalina.out?
If nothing there - comment out the "loglevel 0" line in /opt/zimbra/conf/slapd.conf and restart ldap - ldap may log something the next time it occurs. |