H3C Technologies H3C SR8800 - Manual (Page 89)

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Configuration prerequisites
Before you configure CR-LSP backup, complete the following tasks:
• Configure MPLS basic capabilities
• Configure MPLS TE basic capabilities
• Configure MPLS TE tunnels
Configuration procedure
To configure CR-LSP backup:
Step Command Remarks
1. Enter system view of the
ingress node.
system-view N/A
2. Enter MPLS TE tunnel interface
view.
interface tunnel tunnel-number N/A
3. Configure the backup mode
used by the TE tunnel.
mpls te backup { hot-standby |
ordinary } Tunnel backup is disabled by
default.
4. Submit current tunnel
configuration.
mpls te commit N/A
NOTE:
CR-LSP backup should be configured at the ingress node of a tunnel. The system routes the primary LSP
and backup LSP automatically. You do not need to configure them.
Configuring FRR
NOTE:
The FRR feature is not supported when the signaling protocol is CR-LDP.
As mentioned earlier, Fast Reroute (FRR) provides quick but temporary per-link or per-node local
protection on an LSP.
FRR uses bypass tunnels to protect primary tunnels. As bypass tunnels are pre-established, they require
extra bandwidth and are usually used to protect crucial interfaces or links only.
You can define which type of LSP can use bypass LSPs, and whether a bypass LSP provides bandwidth
protection as well as the sum of protected bandwidth.
The bandwidth of a bypass LSP is to protect its primary LSPs. To guarantee that a primary LSP can always
bind with the bypass LSP successfully, make sure that the bandwidth assigned to the bypass LSP is not less
than the total bandwidth needed by all protected LSPs.
Normally, bypass tunnels only forward data traffic when protected primary tunnels fail. To allow a
bypass tunnel to forward data traffic while protecting the primary tunnel, you need to make sure that
bypass tunnels are available with adequate bandwidth.
A bypass tunnel cannot be used for services like VPN at the same time.