Mac OS X in a Nutshell

Name

traceroute

Synopsis

traceroute [options] host [packetsize]

Traces route taken by packets to reach network host. traceroute attempts tracing by launching UDP probe packets with a small TTL (time to live), then listening for an ICMP “time exceeded” reply from a gateway. host is the destination hostname or the IP number of host to reach. packetsize is the packet size in bytes of the probe datagram. Default is 38 bytes.

Options

-d

Turn on socket-level debugging.

-m max_ttl

Set maximum time-to-live used in outgoing probe packets to max-ttl hops. Default is 30 hops.

-n

Show numerical addresses; do not look up hostnames. (Useful if DNS is not functioning properly.)

-p port

Set base UDP port number used for probe packets to port. Default is (decimal) 33434.

-q n

Set number of probe packets for each time-to-live setting to the value n. Default is 3.

-r

Bypass normal routing tables and send directly to a host on an attached network.

-s src_addr

Use src_addr as the IP address that will serve as the source address in outgoing probe packets.

-t tos

Set the type-of-service in probe packets to tos (default 0). The value must be a decimal integer in the range 0 to 255.

-v

Verbose—received ICMP packets (other than TIME_EXCEEDED and PORT_ UNREACHABLE) will be listed.

-w wait

Set time to wait for a response to an outgoing probe packet to wait seconds (default is 3 seconds).