LTM Packet Filters Health Monitor Probes

By default the packet rules accept all traffic. They also accept all traffic that matches an existing connection. So unless you explicitly configure a rule to deny, it will be allowed. You can view existing connections via the connection table using standard tmsh commands (tmsh show sys conn) but be aware that this can take a while to run on a busy box, and cancelling it can cause tmm to core.

As such we really don't normally maintain a table for packet filters. You should not need to explicitly allow ICMP Echo response, but if you think your packet filters are catching your responses, you can try setting Allow Important ICMP and see if the observed behavior changes.