Configuring Frr; Configuration Prerequisites; Configuration Procedure - 3Com MSR 50 Series Configuration Manual

Configuring FRR

Configuration
Prerequisites

Configuration Procedure

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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.
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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 forward data traffic while protecting the primary
tunnel, you need to ensure that bypass tunnels are available with adequate
bandwidth.
A bypass tunnel cannot be used for services like VPN at the same time.
Before configuring FRR, do the following:
Configure IGP, ensuring that all LSRs are reachable
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Configure MPLS basic capabilities
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Configure MPLS TE basic capabilities
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Establish an MPLS TE tunnel with RSVP-TE
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Set up primary LSPs
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Configuring FRR involves these tasks:
"Enabling FRR on the headend of a primary LSP" on page 1381
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"Configuring a bypass tunnel on its PLR" on page 1382
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"Configuring node protection" on page 1383
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"Configuring the FRR polling timer" on page 1383
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Enabling FRR on the headend of a primary LSP
Follow these steps to enable FRR on the headend of a primary LSP:
To do...
Enter system view
Use command to...
system-view
Configuring FRR 1381
Remarks
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