If I do ping 8.8.8.8 sometimes it returns the following for a period of time:
From 172.22.1.1 icmp_seq=36 Destination Host Unreachable
But at other times it does reach the target and yet it says there is packet loss. Even if I do a ping and the aforementioned error message is never produced, it says about 30% packet loss when the ping session is stopped.
Someone told me this could mean that the packets are going through eventually because the unreachable message is not shown. Is this true?
Best Answer
If the message is "Destination Host Unreachable," then there is no route from the local system, and the packets to be sent were never put on the wire. Those requests will be reported as 0% loss, since nothing was ever sent out.
Now, if the message says "From 10.x.x.x icmp_seq=1 Destination Host Unreachable" (10.x.x.x being an IP other than your own), the packets will be reported as a loss. Because those packets let your machine, but for some reason were blocked along the line.
Also, if you do not receive one or more ping requests back, without that error message, that could be for any number of reasons. Those will be reported as packet loss.