I'd like to check for NULL sender in 'MAIL FROM:' but only from hosts
outside our local domain (to stop outgoing list messages that came in
with NULL sender from being rejected further down the line by other
remote MTAs). Inter-domain failures need to go back through our MTA to
get to the original sender.
With headers_sender_verify_errmsg set, all SMTP connections are checked
regardless of the setting of sender_verify_hosts.
local machine is running exim in 'dumb' mode where it throws *all*
email at our MTA.
local -> MTA : initiates SMTP session for an unknown user
MTA -> local : MTA rejects message at SMTP level
local -> MTA : tries to send failure report to original sender
MTA -> local : MTA rejects mail with
550 rejected: no valid sender in message headers: return path is <>
local : failure report is frozen (lost)
Should the setting of sender_verify_hosts affect the operation of
headers_sender_verify_errmsg? If not, is there a way around this?
NB. This works if we switch off headers_sender_verify_errmsg, but then
we end up with frozen junk in our queues (from lists) that originally
came in with a NULL sender.
MTA is running v3.0.3
Cheers,
Wilf.
--
Dr Graeme Wilford EEIT&M Computer Support and IT Manager
School of EEIT&M Phone: +44 (0)1483 259125 Room: 16aAB22
University of Surrey Fax: +44 (0)1483 259554
Guildford email: G.Wilford@???
Surrey GU2 5XH, UK http://www.ee.surrey.ac.uk/
