Brocade Network Advisor SAN + IP User Manual v12.3.0 - Manual (Page 1554)

1482 Brocade Network Advisor SAN + IP User Manual
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LSP
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From the Fast Reroute tab you can configure an LSP to request a facility backup provided by a
bypass LSP in the event of a failure along the LSP path. Each LSR in an LSP except the egress
router may act as a Point of Local Repair (PLR). If a failure occurs on an LSP, the PLR tries to
initiate a bypass LSP to provide a backup route for the protected path. The PLR then becomes
the ingress of a bypass LSP. The bypass LSP carries the traffic of the LSPs it protects around
the break. The point past the break where traffic re-enters is called the merge point.
In Figure 672 , R2 is the PLR. The double line that originates at R2 and then traverses R6 and
R7 to terminate at R4 is the bypass LSP. The bypass LSP terminates in R4 and traffic merges
back into the protected LSPs. This router is the merge point and the egress router for the
bypass LSP.
FIGURE 672 Bypass LSP
When you use fast reroute to request a facility backup, the characteristics of the backup LSP
should match well with the LSP that is requesting the facility backup:
- The value specified in the Detour Bandwidth/Backup LSP and the Hop Limit fields should
be the same as the requesting LSP.
- Select the Request Facility Backup checkbox to enable the facility backup request.
- Setup Priority and Hold Priority should be the same as the requesting LSP.
- Admin group Include All, Include Any, and Exclude Any selections should be the same as
the requesting LSP. Use the Select buttons to display the Admin Groups Selector dialog box
(
Figure 668 ).
R1
R6 R7
R3 R4 R2 R5