ICMP

anthic.lobo · ‎10-14-2009

What is the difference between

icmp permit any echo OUTSIDE and

icmp permit any echo-reply OUTSIDE

...

Which one of the two will stop me from disabling pic to the ASA from outside.

Collin Clark · ‎10-14-2009

Suppose Device A wants to see if it can reach Device B. Device A begins the test process by sending an ICMPv4 Echo message to B. Device B, when it receives the Echo, responds back to Device A with an Echo Reply message. When Device A receives this message, it knows that it is able to communicate (both send and receive) successfully with Device B.

Can you rephrase your 2nd question?

anthic.lobo · ‎10-16-2009

So does this mean that i need to allow both echo reply and echo for me to ping the device

Collin Clark · ‎10-16-2009

Echo-reply for sure and if you'll be pinging from the device, you'll need echo as well.