I am allowing specific internal hosts to relay through the Ironport. It works fine when using the IP address, but will not work using the hostname.
When telneted into the Ironport, I can ping the hostname, so DNS appears to be working.
DNS is setup as follows:
Priority IP Address
0 DMZ DNS Host IP (for DMZ computer host resolution)
1 ISP DNS Host - Primary
1 ISP DNS Host - Secondary
Overriding with the DNS Servers listed below:
Domain IP Address
internal.domain.com *.*.*.* (internal DNS server)
Typical internal hostname: computer1.internal.domain.com
Am I missing something here?