Reference Guide

Figure 5. MPLS Core

Link trace messages carry a unicast target address (the MAC address of an MIP or MEP) inside a multicast frame. The

destination group address is based on the MD level of the transmitting MEP (01:80:C2:00:00:3[8 to F]). The MPs on the

path to the target MAC address reply to the LTM with an LTR, and relays the LTM towards the target MAC until the

target MAC is reached or TTL equals 0.

• Send a Linktrace message. Because the LTM is a Multicast message sent to the entire ME, there is no need to

specify a destination.

EXEC Privilege

traceroute ethernet domain

Caching Link Trace

After you execute a Link Trace command, the trace information can be cached so that you can view it later without

retracing.

To enable, set, display, and delete link trace caching, use the following commands.

• Enable Link Trace caching.

CONFIGURATION mode

traceroute cache

• Set the amount of time a trace result is cached.

ETHERNET CFM mode

traceroute cache hold-time minutes

The default is 100 minutes.

The range is from 10 to 65535 minutes.

• Set the size of the Link Trace Cache.

ETHERNET CFM mode

traceroute cache size entries