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Determines the path a packet takes to get to a destination. The device sends out a sequence of User Datagram Protocol (UDP)
datagrams to an invalid port address at the remote host.
traceroute <A.B.C.D> [source-ip <ip addr> | hostname <name>] [min-ttl <int>] [max-ttl <int>] [timeout
<int>] [probe-count <int>] [port-number <int>] [tos <0 | 0..255>]
Three datagrams are sent initially, each with a Time-To-Live (TTL) field value set to one. The TTL value of 1 causes the datagram
to "timeout" as soon as it hits the first router in the path. A response is then received with an ICMP Time Exceed Message
(TEM) indicating that the datagram has expired.
Note: The configure ip vrf default icmp-time-exceeded command must be run or traceroute through the CMTS will not
work
Another three UDP messages are now sent, each with the TTL value set to 2 which causes the second router to return ICMP
TEMs. This process continues until the packets actually reach the other destination. Since these datagrams are trying to access
an invalid port at the destination host, ICMP Port Unreachable Messages are returned, indicating an unreachable port, this
event signals the Traceroute program that it is finished.
Traceroute can also execute from the System Control Module ethernet port. If the source-ip option specifies the RCM’s IP
address, then the traceroute will be sourced from the SCM’s ethernet port. The purpose behind this is to record the source of
each ICMP Time Exceeded Message to provide a trace of the path the packet took to reach the destination from a given source
by returning the sequence of hops the packet has traveled.
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