traceroute

The traceroute utility displays the route used by IP packets on their
way to a specified network (or Internet) host.  Traceroute displays
the IP number and host name (if possible) of the machines along the
route taken by the packets.  Traceroute is used as a network debugging
tool.  If you're having network connectivity problems, traceroute will
show you where the trouble is coming from along the route.

Install traceroute if you need a tool for diagnosing network connectivity
problems.