Postfix version 2.5.6 being used as a relay for chatty internal processes.
Suddenly, one of them is complaining of this error, in the midst of a 250 ish recipient email. With attachment of some size. ". . .postfix/smtpd[15953]: NOQUEUE: reject: MAIL from unknown[192.168.aa.bb]: 452 4.3.1 Insufficient system storage; proto=ESMTP helo=<SUM-Host-name>" Seems this may be telling me the machine was out of disk space or a Queue was limited in some way, but I have about 4GB of free space. I am attempting to determine the size of the mailing list from the sender, the attachment is 2MB or so. Simple issue, eluding me?
