““First, take a moment to review the output of the first IOS ping command. By default, the Cisco IOS ping command sends five echo messages, with a timeout of 2 seconds. If the command does not receive an echo reply within 2 seconds, the command considers that message to be a failure, and the command lists a period. If a successful reply is received within 2 seconds, the command displays an exclamation point. So, in this first command, the first echo reply timed out, whereas the other four received a matching echo reply within 2 seconds.””
