Print the route packets take to network host.
Syntax
traceroute [options] host [packetsize]
Options:
-I Use ICMP ECHO for probes
-T Use TCP SYN for probes
-U Use UDP datagrams for probes (default). Only UDP is allowed for unprivileged users.
-d Enable socket level debugging (when the Linux kernel supports it)
-F Set the "Don't Fragment" bit. This tells intermediate routers not to fragment
the packet when they find it's too big for a network hop's MTU.
-f first_ttl
With what TTL to start. Default = 1
-g gateway
Adds an IP source route gateway to the outgoing packet. Not useful, as
most routers have disabled this for security reasons.
-i interface
The interface through which traceroute should send packets.
Default = select according to the routing table.
-m max_ttl
The max no. of hops (max time-to-live value) traceroute will probe. Default=30 hops
-N squeries
The number of probe packets sent out simultaneously. Sending several probes
concurrently can speed up traceroute considerably. Default = 16
Note that some routers and hosts can use ICMP rate throttling. In such a situation
specifying too large number can lead to loss of some responses.
-n Show numerical addresses; do not look up hostnames.
(Useful if DNS is not functioning properly.)
-p port
For UDP tracing: the destination port base traceroute will use
(the destination port number will be incremented by each probe).
For ICMP tracing: the initial icmp sequence value (incremented by each probe).
For TCP tracing: the (constant) destination port to connect.
-t tos
For IPv4, set the Type of Service (TOS) and Precedence value.
Useful values are 16 (low delay) and 8 (high throughput).
Note that in order to use some TOS precendence values, you have to be super user.
For IPv6, set the Traffic Control value.
-w waittime
Set the time (in seconds) to wait for a response to a probe (default 5.0 sec).
-q nqueries
Set the number of probe packets per hop. Default = 3
-r Bypass the normal routing tables and send directly to a host on an attached network.
If the host is not on a directly-attached network, an error is returned.
This option can be used to ping a local host through an interface that has no route through it.
-s source_addr
Choose an alternative source address. You must select the address of one of the interfaces.
Default = address of the outgoing interface.
-z sendwait
Minimal time interval between probes (default 0). If the value is more than 10,
then it specifies a number in milliseconds, else it is a number of seconds
(float point values allowed too). Useful when some routers use rate-limit for icmp messages.
-A Perform AS path lookups in routing registries and print results directly after
the corresponding addresses
-V Print the version and exit.
--help Print help info and exit.
-4, -6 Explicitly force IPv4 or IPv6 traceouting. By default, the program will try
to resolve the name given, and choose the appropriate protocol automatically.
If resolving a host name returns both IPv4 and IPv6 addresses, traceroute will use IPv4.
"The Net interprets censorship as damage and routes around it" ~ John Gilmore
Related linux commands:
mtr - Network diagnostics (traceroute/ping).
netstat(1)
ping(8)
route - manipulate routing tables.
Equivalent Windows command: tracert - Trace Route.