正解:D
When executing a traceroute command, if the result shows asterisks (*) for a hop, it indicates that the probe sent did not receive a reply within the expected time frame, usually meaning that the probe timed out. In this scenario, since the last line of the traceroute output shows "3 10.10.10.1 * * *", it confirms that the probe sent to this hop has timed out.
In Cisco routers, the codes for a traceroute command reply are:
! - success* - time outN - network unreachableH - host unreachableP - protocol unreachableA - admin deniedQ - source quench received (congestion)? - unknown (any other ICMP message)In Cisco routers, the codes for a traceroute command reply are:
! - success* - time outN - network unreachableH - host unreachableP - protocol unreachableA - admin deniedQ - source quench received (congestion)? - unknown (any other ICMP message)