- play_arrow Overview
- play_arrow Understanding MPLS
- play_arrow Supported Standards
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- play_arrow MPLS Configuration
- play_arrow Configuring MPLS
- play_arrow Configuring MPLS Tunnels
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- play_arrow MPLS Traffic
- play_arrow Managing MPLS Traffic
- play_arrow Protecting MPLS Traffic
- play_arrow Measuring MPLS Traffic
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- play_arrow MPLS Signalling Protocols
- play_arrow RSVP
- play_arrow LDP
- LDP Overview
- LDP Configuration
- Example: Configuring Multiple-Instance LDP
- Tunneling LDP over SR-TE
- Example: Tunneling LDP over SR-TE in IS-IS Network
- Example: Tunneling LDP over SR-TE in OSPF Network
- MPLS TTL Propagation Flexibility for LDP-signaled LSPs
- Example: Configuring MPLS TTL Propagation for LDP-signaled LSPs
- Understanding Multipoint LDP Recursive FEC
- Example: Configuring Multipoint LDP Recursive FEC
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- play_arrow MPLS Traffic Engineering
- play_arrow Configuring MPLS Traffic Engineering
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- play_arrow MPLS Transport Profile
- play_arrow Operation, Administration, and Maintenance (OAM) for MPLS
- play_arrow MPLS Pseudowires
- play_arrow Class-of-Service (CoS) for MPLS
- play_arrow Generalized MPLS (GMPLS)
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- play_arrow MPLS VPNs and Circuits
- play_arrow Ethernet over MPLS (L2 Circuit)
- play_arrow CCC, TCC, and Layer 2.5 Switching
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- play_arrow MPLS for Software Defined Networking (SDN)
- play_arrow Path Computation Element Protocol (PCEP)
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- play_arrow MPLS Troubleshooting
- play_arrow Troubleshooting MPLS
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- play_arrow Configuration Statements and Operational Commands
Adaptive LSP Configuration
An LSP occasionally might need to reroute itself for these reasons:
The continuous reoptimization process is configured with the
optimize-timer
statement.The current path has connectivity problems.
The LSP is preempted by another LSP configured with the
priority
statement and is forced to reroute.The explicit-path information for an active LSP is modified, or the LSP’s bandwidth is increased.
You can configure an LSP to be adaptive when it is attempting to reroute itself. When it is adaptive, the LSP holds onto existing resources until the new path is successfully established and traffic has been cut over to the new LSP. To retain its resources, an adaptive LSP does the following:
Maintains existing paths and allocated bandwidths—This ensures that the existing path is not torn down prematurely and allows the current traffic to continue flowing while the new path is being set up.
Avoids double-counting for links that share the new and old paths—Double-counting occurs when an intermediate router does not recognize that the new and old paths belong to the same LSP and counts them as two separate LSPs, requiring separate bandwidth allocations. If some links are close to saturation, double-counting might cause the setup of the new path to fail.
By default, adaptive behavior is disabled. You can include the adaptive
statement in two different hierarchy levels.
If you specify the adaptive
statement at the LSP
hierarchy levels, the adaptive behavior is enabled on all primary/secondary
paths of the LSP. This means both the primary and secondary paths
share the same bandwidth on common links.
To configure adaptive behavior for all LSP paths, include
the adaptive
statement in the LSP configuration:
You can include this statement at the following hierarchy levels:
[edit protocols mpls label-switched-path lsp-name]
[edit logical-systems logical-system-name protocols mpls label-switched-path lsp-name]
If you specify the adaptive
statement at the [edit protocols mpls label-switched-path lsp-name (primary | secondary) path-name]
hierarchy
level, adaptive behavior is enabled only on the path on which it is
specified. Bandwidth double-counting occurs between different paths.
However, if you also have the adaptive
statement configured
at the [edit protocols mpls label-switched-path lsp-name]
hierarchy level, it overrides the adaptive behavior of each
individual path.
To configure adaptive behavior for either the primary or secondary
level, include the adaptive
statement:
You can include this statement at the following hierarchy levels:
[edit protocols mpls label-switched-path lsp-name (primary | secondary) path-name]
[edit logical-systems logical-system-name protocols mpls label-switched-path lsp-name (primary | secondary) path-name]