Solaris

I have a Solaris 10 box that has 2 Ethernet connections. One is 172.21.0.150, this is on the main internal LAN. The other is 172.16.0.50 this is the DMZ. I have Apache 2.0.59, I do not care which it Listens to but the main one for it is 172.16.0.50 (DMZ) which I have been explicit (Listen 172.16.0.50:80) and tried bind all (Listen *:80). When I have the system all setup everything works fine from the Internet going to Server.com or external IP (which goes to DMZ 172.16.0.50). But it DOES NOT work when sitting on the 172.21.0.X network (LAN). This tells me that there is a problem in the firewall preventing network 21 getting to port 80 on the 16 network. But if I totally disable the interface that has 172.21.0.150, then everything works fine from the Internet AND from the 21 network going to Server.com.

Any suggestions?

I think you will need to enable routing on your Solaris 10 server so that requests going into your non-DMZ network get forwarded to your DMZ network address, unless you can get Apache to listen on both ports.
Take a look at:
Solaris Routing
and here on the forum at:
Solaris 10 as Router...

Presumably you will not want this server to act as a router for the rest of the network so you will probably want to only add a static route so enable ipv4_routing but not ipv4_forwarding?

HTH