H3C S9500 Series Operation Manual page 1006

Operation Manual – MPLS OAM
H3C S9500 Series Routing Switches
the display mpls oam ingress [ all | lsp-name lsp-name ] verbose command on the
ingress node, the defect-sate field displays No-defect.
II. Solution
The reason for this problem may come from:
The reverse channel is not configured or down. So the egress node cannot notify
the ingress node of defect verification results.
The reverse channel specified by the ingress node is different from that specified
by the egress node.
To solve this problem, you can:
Execute the display mpls oam egress [ all | lsp-name lsp-name ] verbose
command. If the lsp-name field is null in the oam backward information, which
means the reverse channel is not configured. In this case, you should use the
OAM configuration command to configure a reverse channel for the LSP to be
verified.
Both nodes are configured with a reverse channel, but the lsp-state field is down in
the oam backward information. In this case, you should modify MPLS
configuration and make the reverse channel up, or reuse OAM configuration
commands to configure an up reverse channel for the LSP to be verified.
The reverse channel of the egress node is up, but it is different from that
configured on the ingress node. In this case, you should configure the reverse
channel properly on the egress node and the ingress node.
1.5.5 The Defects of the Ingress Node cannot Trigger Protection Switching
I. Symptom
Protection switching is enabled. When you execute the display mpls oam ingress [ all
| lsp-name lsp-name ] verbose on the ingress node, the defect-state field displays In
defect; while you execute the display mpls protect-switch [ protect-id | all ] verbose
command through command line, the Switching Result field displays Working LSP.
II. Solution
The reason for this problem may come from:
The primary LSP is not the one for OAM defect verification.
The secondary LSP also has defects and data flows are not switched.
Holdoff is not zero. You need to wait a period of time before triggering protection
switching.
External switching command restricts the transmission of data flows to the primary
LSP.
To solve this problem, you can:
Chapter 1 MPLS OAM Configuration
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