A new mail loop problem seems to have appeared with the 1.5N2 version
of LISTSERV.  It looks like any time someone on MFENET tries to post
mail to a list via the MFEGATE@ANLVMS gateway, that LISTSERV and the
gateway will get into a mail loop.
 
Prior versions of LISTSERV have not accepted mail sent via MFEGATE
either, but just bounced the mail to the postmaster (or listmaster?),
with an error message stating that MFEGATE@ANLVMS is listed in DOMAIN
NAMES and thus the mail is suspected to be gateway rejection mail.
(The fact that the MFEGATE gateway produces RFC822 mail files
with a filetype of NOTE instead of MAIL seems to be the trigger for
this chain of problems.)  Version 1.5N2, however, rejects the mail
item because the "From:" line does not agree with the NJE Tag origin
(i.e, MFEGATE@ANLVMS) and sends error mail to both the LISTSERV
postmaster and TO THE GATEWAY ITSELF.  The gateway in turn rejects
the mail back to our LISTSERV "because it has invalid BSMTP syntax"
(true -- ANLVMS is listed in XMAILER NAMES as DEFRT 1, so no BSMTP
is used).  Then LISTSERV tries to read the MFEGATE error mail as a
command file, fails of course, and sends another error notification
to the gateway.  Then the loop begins in earnest.
 
Now, you might think that after 10 times around, LISTSERV should have
SERVEd OUT the gateway, and indeed it did.  The 10th error note from
LISTSERV to the gateway even stated that the latter was being cut
off.  However, that did NOT break the loop -- despite the fact that
MFEGATE@ANLVMS had been SERVEd OUT, LISTSERV continued to read mail
from, and send error notices back to, the gateway.  Thus, it looks
like there may be a second LISTSERV problem, in the SERVE OUT area.
 
Eric, Ross, (or anyone else who might be interested in looking
at the problem) --  I have a few hundred lines of LISTSERV console
file listings, plus samples of the initial and error message mail
files, if you'd like to see them -- just let know.
 
--  John Halperin  <[log in to unmask]>
    Stanford Linear Accelerator Center