Traceroute
Linux
traceroute <OPTIONS> <HOST>
By default, sends UDP packets with incrementing destination ports starting at base port of 33434, going up by one port for each probe packet sent (each hop measured three times). Every router dropping the packet because of TTL=0 should respond with a ICMP TTL Exceeded in Transit message with its IP address in the source field.
| Option | Description |
|---|---|
-n |
Do not resolve IP addresses into names |
-I |
Use ICMP Echo Request instead of UDP (mimick Windows default) |
-T |
Use TCP SYN instead of UDP, with default dest port 80 |
-p [port] |
For TCP, set the fixed TCP destination port to use. For UDP, set the base destination UDP port and increment |
-f [N] |
Set the initial TTL for the first packet (if we don’t care about nearby discovery) |
-m [N] |
Set the maximum number of hops (default: 30) |
-4 |
Force use of IPv4 |
-6 |
Force use of IPv6 |
Tip
When the default traceroute does not work, try with -I and -T options.
Windows
tracert <OPTIONS> <HOST>
By default, sends ICMP Echo Request messages probes, each hop is measured three times. Every router dropping the packet because of TTL=0 should respond with a ICMP TTL Exceeded in Transit message with its IP address in the source field.
| Option | Description |
|---|---|
-d |
Do not revole IP addresses into names |
-h [N] |
Set the maximum number of hops (default: 30) |
-4 |
Force use of IPv4 |
-6 |
Force use of IPv6 |