I'm experiencing a strange problem with NATing on a PIX 515 running 6.3. I have 2 statements:
nat (inside) 1 10.0.0.0 255.0.0.0
global (DMZ2) 1 192.168.194.0 netmask 255.255.254.0
With this config I can get no packets at all to pass from the inside and out of the DMZ2 interface (using debug any any on both interfaces). Yet when I change the global to a /8 mask (i.e 192.0.0.0) packets pass through fine. I've noticed on the debug trace that the source port is altered even where the subnets are of equal size on the nat and global (i.e where both subnets are /8 Port address translation is occurring) so I'm at a loss why the larger (/8) pool cannot be translated sucessfully to the smaller (/23) pool.
Does anyone know of a bug in the software or am I missing some config?