Pretty sure the pb was on the client's site, we went and saw somebody had made a change somewhere so that the exchange machine wasn't looking up to our DNS (across a ded line, over which ip was working perfectly) anymore. We fixed that and all is ok.
The symptoms were pretty weird, esp the behaviour of the Exchange Internet connector and how Imail interacted with it in those DNS-absent conditions.
Our Imail is the 2ndary MX (inbound) and outbound relay for this client's Exchange, so that's why Imail was sending the failed msg's to itself, perhaps similar to your situation. The exchange machine is therefore in our Imail's hosts file. see below on this hosts issue
Handshaking would work to the point where Imail would send a msg to exchange and even log an rdeliver line (so rdiver really means that the msg was sent (ie smtp traffic), but does not mean it was delivered, ie, it's , but then also queue the msg. It looks like imail wasn't getting an recd-OK post-delivery.
re-attempting the queued msg included another transmission to exchange, followed by exchange saying "this msg already received".
We still have a ton of relayed msgs in the \spool directory from this situation, but none show up in Imail's queue.
Just when we thought we had Imail pretty well understood..... vbg
Say the primary mailserver for a domain is machine1.domain.com and the
backup machine is called machine2.domain.com. The MX records for the domain
show:
IN MX 10 machine1.domain.com
IN MX 20 machine2.domain.com
On machine2, I modified the hosts file with a line like:
1.1.1.1 machine1.clientdomain.com
our client's clientdomain.com and exhange.clientdomain.com are two different machines. In Imail's hosts fils, we have
x.x.x.x exchange.clientdomain.com
since the outbound/to-internet relaying we want to enable is from the exchange.clientdomain.com machine, and not from the clientdomain.com machine.
do you, and Ispwitch??, recommend I change my hosts file to
x.x.x.x clientdomain.com
where x.x.x.x is the ip address of the exchange.clientdomain machine and not the address of the clientdomain.com machine??
Another phrasing: is the NT hosts file, as used by Imail, for domains (and all hosts in that domain, ie, my exchange.clientdomain.com) or for machines?? or both?
Thanks,
Len
