There are a number of reasons for lost responses from icmp. It depends upon the type of response. If its because of the network unreachability then One of the methods is to do a trace to the same IP & see where it reaches. Then start troubleshooting from the point of last hop visible in the trace.
There can be number of reasons for this:
no route to destination
destination is not up
assymetric path etc.
there is no specific command to chk the icmp connectivity.
bhartiji, first ensure that the node you are trying to ping is UP on network. One way of doing it is to ping it from the nearest switch such that firewall doesnt come in to picture.
Then find out with security team what tcp port is open on firewall for this server. Try telnet to the server on this port(telnet x.x.x.x portnumber) from local network where the server is. Ensure firewall doesnt come in to picture.
if it gives a blank screen, then application is UP on server.
These 2 tests ensure that your sever & application are both working.
Now repeat the tests from behind the firewall. Trace should reach up to the nearest hop to firewall. Then the issue is with firewall config.
But if trace doesnt reach till firewall or hop before that, then check routing till destination.
ICMP is a collection of various messages (about 30 of them) that are often treated very differently. What exact ICMP message seems to be getting lost ? If you are loosing the odd ICMP-ECHO-REPLY, it's likely no big deal. If you are not getting an ICMP-ADDRESSMASK-RELY then maybe the device does not support it. ICMP-SOURCEQUENCH is one that I have never seen on a wire, not that I look for everything. Firewalls tend to not send out ICMP-REDIRECTS, but that may be configurable.
Bottom line, ICMP is a broad 'protocol' and more details are required to help solve whatever issue you may have, imo.
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