3com S7906E 설치 설명서

 

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CR-LSP backup provides end-to-end path protection to protect the entire LSP.  

Before configuring CR-LSP backup, do the following: 

z

 

Configure MPLS basic capabilities  

z

 

Configure MPLS TE basic capabilities 

z

 

Configure MPLS TE tunnels 

Follow these steps to configure CR-LSP backup: 

Enter system view of the 
ingress node 

–– 

Enter MPLS TE tunnel interface 
view 

 tunnel 

 

–– 

Configure the backup mode 
used by the TE tunnel 

{ hot-standby 

| ordinary } 

Required 
Tunnel backup is disabled by 
default.  

Submit current tunnel 
configuration 

Required 

 

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.  

 

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 forward data traffic while protecting the primary tunnel, you need to ensure that bypass 
tunnels are available with adequate bandwidth.