Question

If you receive the error "Destination Host Unreachable" while pinging, what would be the best interpretation?

A.The end host is onlineB.A Layer 3 problem exists between the two hostsC.A Layer 5 problem exists between the two hostsD.The end host is offlineE.A Layer 1 problem exists between the two hosts

Answer 1

PING ERROR: "Destination Host Unreachable"

The best interpretation will be option (d) The end host is offline.

Explanation:

"Destination Host Unreachable" error occurs when the local system or a remote system responsible for routing the packet is unable to route to the destination.

** "Destination Host Unreachable" is basically the computer saying "I don't know where to send the packet, the host is either offline and didnot respond to ARP or I don't know where to route the packets"

There are basically two interpretation for this Ping error:

a) If the message is simply "Destination Host Unreachable" then there is no route from the local system and the packet to be sent were never put on the wire

b) If the message is "Reply from <IP Address> Destination Host Unreachable" then the routing problem occured at a remote router, whose address is indicated by the IP Adress field