If a network condition prevents traceroute from reaching the destination
Common reasons for
traceroute failing to reach a destination include:
Timeouts (indicated by one asterisk per probe, per hop)
Unreachable hosts
Unreachable networks
Interference from firewalls
Hosts configured to avoid responding
Executing
traceroute where the route becomes blocked or otherwise fails results in an output marked by timeouts for all probes beyond the last detected hop. For example, with a maximum hop count of 7 (maxttl = 7), where the route becomes blocked or otherwise fails, the output appears similar to this:
