Ok first post ever, could use some help on this issue. I will just list it as plain as I can.

Linux router = eth0 x.x.x.x eth1/br0 = 192.168.88.1
exchange Server = 192.168.88.10
Linux Spam server = 192.168.88.4
PBX Server = 192.168.88.150

*PROBLEM* I can't send an email from the PBX server to my exchange server. The PBX server resolves the public IP of the linux router but can't get back to the exchange server.

Typical email route for my domain.

mail comes to Linux router, PRE NAT sends it to The spam server. Spam server then routs it to exchange server.

When I am on the PBX server in a shell and try to telnet to mail.mydomain.com 25 it hangs. I want the Linux router to route my request as if i was on the outside.

Please advise.

Hi,

The PBX server's host file does not contain the exchange server's IP.

There are two solution for this problem.

Easy one:

Put the exchange server's IP address and name into the hosts file on the machines that you want to reach from.
Basically the PBX /etc/hosts file has to have this entry:
Complicate one:

Install a local DNS server which contains all the local machine's IP addresses and names for name resolution.

I guess the first one is the easy way.

Or you can simply send mails from the PBX machine with IP address instead of name(s).

Regards,

Laz