ASA 5525 firewall Trace Route.

Question

Hi,
We are Having  ASA 5525 firewall and Whenever I am performing traceroute passing through the firewall and i am not getting any hop count after firewall( Firewall IP is also not shwoing in Trace Route.
ICMP I had allowed and also configure ICMP in the Policy_Map global Policy.
PLease help me to resolve this issue.
Regards,
Dheeraj

Answer 1

Hi Dheeraj,
     firewall blocks Traceroute as doesnt decrements the TTL value by default. You would need the following to enable the same:
Make the Firewall Show Up in a Traceroute in ASA/PIX
ciscoasa(config)#class-map class-default
ciscoasa(config)#match any
!--- This class-map exists by default.
ciscoasa(config)#policy-map global_policy
!--- This Policy-map exists by default.
ciscoasa(config-pmap)#class class-default
!--- Add another class-map to this policy.
ciscoasa(config-pmap-c)#set connection decrement-ttl
!--- Decrement the IP TTL field for packets traversing the firewall.
!--- By default, the TTL is not decrement hiding (somewhat) the firewall.
ciscoasa(config-pmap-c)#exit
ciscoasa(config-pmap)#exit
ciscoasa(config)#service-policy global_policy global
!--- This service-policy exists by default.
WARNING: Policy map global_policy is already configured as a service policy
ciscoasa(config)#icmp unreachable rate-limit 10 burst-size 5
!--- Adjust ICMP unreachable replies:
!--- The default is rate-limit 1 burst-size 1.
!--- The default will result in timeouts for the ASA hop:
Cheers,
Naveen