$ traceroute

Trace the path from this server to a host, with per-hop latency, reverse DNS and ASN. Choose the probe protocol: ICMP (default), TCP SYN to a real port (passes firewalls that drop ICMP; the last hop shows whether the port is open) or UDP to DNS/NTP ports. All hops are probed in parallel, so it finishes in a few seconds. IPv4 targets. For repeated measurements use mtr.