H3C Technologies H3C S12500 Series Switches - Manual (Page 38)

27
Step Command Remarks
2. Configure the interval field
value in the CCM messages
sent by MEPs.
cfd cc interval interval-value
service-instance instance-id Optional.
By default, the interval field value is 4.
3. Enter Layer 2 Ethernet
interface view. interface interface-type
interface-number
N/A
4. Enable CCM sending on a
MEP.
cfd cc service-instance
instance-id mep mep-id
enable
By default, CCM sending on a MEP is
disabled.
Configuring LB on MEPs
The LB function can verify the link state between the local MEP and the remote MEP or MIP.
To configure LB on a MEP:
Task Command Remarks
Enable LB.
cfd loopback service-instance
instance-id mep mep-id
{ target-mep target-mep-id |
target-mac mac-address } [ number
number ]
By default, LB is disabled.
Available in any view.
Configuring LT on MEPs
LT can trace the path between the source and target MEPs, and can also locate link faults by sending LT
messages automatically. The two functions are implemented in the following way:
• To implement the first function, the source MEP first sends LTM messages to the target MEP. Based
on the LTR messages in response to the LTM messages, the path between the two MEPs can be
identified.
• In the latter case, after LT messages automatic sending is enabled, if the source MEP fails to receive
the CCM frames from the target MEP within 3.5 times the transmission interval, the link between the
two is considered faulty and LTM frames (with the target MEP as the destination and the TTL field in
the LTM frames set to the maximum value 255) will be sent out. Based on the LTRs that the MIPs return,
the fault source can be located.
To configure LT on MEPs:
Step Command Remarks
1. Find the path between a
source MEP and a target MEP.
cfd linktrace service-instance
instance-id mep mep-id { target-mep
target-mep-id | target-mac
mac-address } [ ttl ttl-value ] [ hw-only ]
Available in any view.
2. Enter system view. system-view N/A
3. Enable LT messages automatic
sending. cfd linktrace auto-detection [ size
size-value ] By default, LT messages
automatic sending is disabled.