Can't send mail via DNS

[jshepherd]

Brief story. Had an Exchange 2003 server running on Windows 2000 for a few years. Never managed to send mail via DNS, only SmartHost. OS on server started to die so migrated Exchange to a temp server running a fresh install of Windows 2003. All worked well and server even sent via DNS.

Just finished rebuilding old mail server and is now running a fresh install of Windows 2003 like the temp server. Just finished moving mailboxes and public folders etc. and was nearly ready to close down temp server when I noticed that the new one wasn’t sending via DNS - it does send via SmartHost though. When I change the Bridgehead server back to the temp server in the Mail Connector, all mails sends via DNS straight away. When I change it back to the new server mail just sits there and doesn’t send – additional queue info says; SMTP could not connect to any DNS server. Can ping FQDN on both servers.

John

 

[jshepherd]

I the changed the IP address of the 'temp server' that did send via DNS to a totally new address and then changed the IP address of 'newly built sever' to the IP address that the temp server was using before (still leaving the network cards teamed). It only went and worked!

I've double-checked every inch of the firewall and there is no setting or block that should have stopped that IP address from working. I guess it just shows that you can't always count on logic.

John