Can you give a specific example?
Most ASA's have a default route yet somehow people still manage to get to more specific routes on the Internet ...
what i am having is that i have a route pointing to interface DMZ with 192.168.0.0/16 for all my branches , but when i try to communicate not working after a while i tried to be more specific , it worked with a route pointing to the subnet it self for example route dmz 192.168.1.0/24
no i did not use the packets tracer , only sh route to verify the routing table and it gave me the below
sh route 192.168.17
Routing entry for 192.168.0.0 255.255.0.0, supernet
Known via "static", distance 1, metric 0
Routing Descriptor Blocks:
* 10.168.11.1, via x
Route metric is 0, traffic share count is 1
There is nothing wrong with using a supernet route.
Have you got any dynamic routing protocols (or even reverse router VPN injection) running that could be injecting more specific routes?