Digisol DG-FS4526E, Management Manual

Page: 458 / 1162

C
HAPTER
15 | Basic Administration Protocols
Connectivity Fault Management
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To show the configured remote maintenance end points:
1.
Click Administration, CFM.
2. Select Configure MEP from the Step list.
3.
Select Show from the Action list.
4. Select an entry from MD Index and MA Index.
Figure 270: Showing Remote Maintenance End Points
T
RANSMITTING
L
INK
T
RACE
M
ESSAGES
Use the Administration > CFM (Transmit Link Trace) page to transmit link
trace messages (LTMs). These messages can isolate connectivity faults by
tracing the path through a network to the designated target node (i.e., a
remote maintenance end point).
CLI R
EFERENCES
"CFM Commands" on page 1023
C
OMMAND
U
SAGE
LTMs 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 (see "Configuring Remote Maintenance End Points" ).
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.
LTMs 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.