From: Martin Horak [mailto:[EMAIL PROTECTED] > > > > Hello courier users. I have a problem with courier server - > > > especially SMTP module. I send a mail through transparent mail > > > proxy on our firewall. When the primary MX of recipient's domain > > > in unreachable, i get this reply from relay: > > > 421 4.4.1 Unable to contact destination > > > > There is no such error message in Courier. > > Of course, this message comes from our damned firewall/mail proxy, > when remote MTA is unreachable. > > > > Other MX records aren't tried and the mail is deferred. I'd like > > > courier to contact backup MX'es before deferring the mail. How > > > can I achieve this? > > > > You can achieve what you want by learning a little bit about SMTP > > first. If the above message is received in response to a delivery > > attempt, the message is interpreted as an indication of a > > temporary failure, and to try again later. That is "later", and > > not "try another mail relay now". Do to otherwise would be a > > behavior more akin of a spam generator, and is likely to get you > > blacklisted as such > > OK, do I have any chance to change Courier's response to this > errorcode (421) from 'try again later' to 'try another relay'? I > really don't want to switch to another mailserver - I'm used to > Courier and i think it has better concept than any other MTA. But > this feature/bug is quite critical for me.
I'm not sure any mailserver will act the way you want. The errorcode 4xx indicates to Courier that it has reached the destination mailserver and has been told to try again later. Since Courier thinks that it has received a response from the primary MX server, it has no reason to attempt the secondary. It looks like your problem is with the proxy. The proxy is acting like an MTA and giving bogus error codes. In other words, it's not quite as transparent as you think. If you allow Courier to use direct outbound SMTP rather than going through the proxy, things would work the way you expect. > One more question: In what circumstances Courier falls back to > backup (secondary) MX? Courier will fall back to the secondary if it does not receive a response from the primary. Bowie ------------------------------------------------------- This SF.Net email is sponsored by: Oracle 10g Get certified on the hottest thing ever to hit the market... Oracle 10g. Take an Oracle 10g class now, and we'll give you the exam FREE. http://ads.osdn.com/?ad_id=3149&alloc_id=8166&op=click _______________________________________________ courier-users mailing list [EMAIL PROTECTED] Unsubscribe: https://lists.sourceforge.net/lists/listinfo/courier-users
