LevelOne GTL-2691 - Manual (Page 1341)

C HAPTER 44 | CFM Commands
Link Trace Operations
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ethernet cfm
linktrace
This command sends CFM link trace messages to the MAC address of a
remote MEP.
S YNTAX
ethernet cfm linktrace {dest-mep destination-mpid | src-mep
source-mpid {dest-mep destination-mpid | mac-address} |
mac-address} md domain-name ma ma-name [ttl number]
destination-mpid – The identifier of a remote MEP that is the target
of the link trace message. (Range: 1-8191)
source-mpid – The identifier of a source MEP that will send the link
trace message. (Range: 1-8191)
mac-address – MAC address of a remote MEP that is the target of
the link trace message. This address can be entered in either of the
following formats: xx-xx-xx-xx-xx-xx or xxxxxxxxxxxx
domain-name – Domain name. (Range: 1-43 alphanumeric
characters)
ma-name – Maintenance association name. (Range: 1-44
alphanumeric characters)
number – The time to live of the linktrace message. (Range: 0-255
hops)
D EFAULT S ETTING
None
C OMMAND M ODE
Privileged Exec
C OMMAND U SAGE
◆ Link trace messages can be targeted to MEPs, not MIPs. Before sending
a link trace message, be sure you have configured the target MEP for
the specified MA.
◆ If the MAC address of target MEP has not been learned by any local
MEP, then the linktrace may fail. Use the show ethernet cfm
maintenance-points remote crosscheck command to verify that a MAC
address has been learned for the target MEP.
◆ Link trace messages (LTMs) are sent as multicast CFM frames, and
forwarded from MIP to MIP, with each MIP generating a link trace reply,
up to the point at which the LTM reaches its destination or can no
longer be forwarded.
◆ Link trace messages are used to isolate faults. However, this task can
be difficult in an Ethernet environment, since each node is connected
through multipoint links. Fault isolation is even more challenging since
the MAC address of the target node can age out in several minutes.
This can cause the traced path to vary over time, or connectivity lost if
faults cause the target MEP to be isolated from other MEPs in an MA.