Brocade Communications Systems Brocate Ethernet Access Switch 6910 - Manual (Page 603)

Brocade 6910 Ethernet Access Switch Configuration Guide 553
53-1002581-01
CFM Commands
25
ethernet cfm linktrace
This command sends CFM link trace messages to the MAC address of a remote MEP.
Syntax
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: 1-43 alphanumeric characters,
maximum length is 44 minus the length of the domain name)
number – The time to live of the linktrace message. (Range: 1-255 hops)
Default Setting
None
Command Mode
Privileged Exec
Command Usage
• 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.
• When using the command line or web interface, the source MEP used by to send a link trace
message is chosen by the CFM protocol. However, when using SNMP, the source MEP can be
specified by the user.