One more question.

sumal

What is the difference between these two commands?

Block all ping messages only to server 192.168.47.5

deny icmp any 192.168.47.5 0.0.0.0
deny icmp any 192.168.47.5 0.0.0.31

This is very confusing to me. Both of these commands will accomplish the same thing.

When should I just use 0.0.0.0 and when should I use a wild card mask?

I think the word "only" is what makes the 0.0.0.0 correct. Is this right?

kplab

"deny icmp any 192.168.47.5 0.0.0.0" denies ICMP traffic destined to the host 192.168.47.5.

"deny icmp any 192.168.47.5 0.0.0.31" denies ICMP traffic destined to all hosts in the subnet 192.168.47.0/27.