An e-mail I was expecting did was expecting a message and it did not arrive. When I checked the transmission log I saw "milter" errors saying "timeout before data read" and "to error state". What is going on? Is there a problem with my antispam server?

Your PerfectMail server is made of components connected through something called Milter (mail filter). The Milter interface allows the anti-spam component to integrate with the Mail Transport Agent component (MTA) on your PerfectMail server.

When a mail server does not properly complete a mail transmission, either by dropping the connection or due to a timeout, the communication channel is broken. This shows up in your log file as a "Milter Error". This is simply an error notification showing that there was a timeout issue.

Following is an example to demonstrate this behavior:

Jul 20 09:45:40 perfectmail sendmail[19312]: rzKgjD5s029413: from=<sender@somedomain.com>, size=7935, class="0", nrcpts=1, msgid=<83785233522355324@mailhost.somedomain.com>, proto=ESMTP, daemon=MTA, relay=mailhost.somedomain.com [10.50.31.69]
Jul 20 09:56:12 perfectmail sendmail[19312]: r7KGjD5s029413: Milter (pm): timeout before data read
Jul 20 09:56:12 perfectmail sendmail[19312]: r7KGjD5s029413: Milter (pm): to error state
Jul 20 09:56:12 perfectmail sendmail[19312]: r7KGjD5s029413: to=<person@yourdomain.com>, delay=00:10:32, pri=37935, stat=Please try again later
 
You can see the time span from the first to the second line of the log file. It took over 10 minutes for the sending server to transmit some very basic information (from and to), which timed out the mail connection.

Keywords: email, antispam, milter, data, transmission, error, timeout, server