3com S7906E Installationsanweisungen
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A bypass tunnel cannot be used for services like VPN at the same time.
Configuration Prerequisites
Before configuring FRR, do the following:
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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
Configuration Procedure
Configuring FRR involves these tasks:
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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…
Use the command...
Remarks
Enter system view
system-view
––
Enter tunnel interface view of
the primary LSP
the primary LSP
interface tunnel
tunnel-number
––
Enable FRR
mpls te fast-reroute
Required
Disabled by default
Disabled by default
Submit current tunnel
configuration
configuration
mpls te commit
Required
Configuring a bypass tunnel on its PLR
After a tunnel is specified to protect an interface, its corresponding LSP becomes a bypass LSP. Setting
up a bypass LSP must be manually performed on its headend, also called point of local repair (PLR),
which must be a part of the primary LSP but must not be the tail of the primary LSP.
up a bypass LSP must be manually performed on its headend, also called point of local repair (PLR),
which must be a part of the primary LSP but must not be the tail of the primary LSP.
Configuring a bypass LSP is the same as configuring a common LSP except that you cannot configure
the FRR attribute on a bypass LSP. In other words, an LSP cannot be both primary and bypass. In
addition, nested LSP protection is not allowed.
the FRR attribute on a bypass LSP. In other words, an LSP cannot be both primary and bypass. In
addition, nested LSP protection is not allowed.
When specifying a bypass tunnel for an interface, make sure that:
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The bypass tunnel is up.
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The protected interface is not its own outgoing interface.
Up to three bypass tunnels can be specified for a protected interface. The best-fit algorithm is used to
determine which of them should be used in case failure occurs.
determine which of them should be used in case failure occurs.
Your device has restriction on links that use the same bypass tunnel so that their total bandwidth does
not exceeds a specified value.
not exceeds a specified value.