Mpls Fast Re-Route (Frr); Manual Bypass Lsp - Alcatel-Lucent 7210 SAS M User Manual

MPLS

MPLS Fast Re-Route (FRR)

The MPLS facility bypass method of MPLS Fast Re-Route (FRR) functionality is extended to the
ingress node.
The behavior of an LSP at an ingress LER with both fast reroute and a standby LSP path
configured is as follows:
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Manual Bypass LSP

The 7210 SAS supports Manual bypass tunnels, on implementation of the Manual bypass feature a
LSP can be pre-configured from a PLR which is used exclusively for bypass protection. If a path
message for a new LSP requests for bypass protection, the node checks if a manual bypass tunnel
satisfying the path constraints exists. If a tunnel is found, it is selected. If no such tunnel exists by
default, the 7210 SAS dynamically signals a bypass LSP.
Users can disable the dynamic bypass creation on a per node basis using the CLI.
A maximum of 1000 associations of primary LSP paths can be made with a single manual bypass
at the PLR node. If dynamic bypass creation is disabled on the node, it is recommended to
configure additional manual bypass LSPs to handle the required number of associations.
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When a down stream detour becomes active at a point of local repair (PLR):
The ingress LER switches to the standby LSP path. If the primary LSP path is repaired
subsequently at the PLR, the LSP will switch back to the primary path. If the standby goes
down, the LSP is switched back to the primary, even though it is still on the detour at the
PLR. If the primary goes down at the ingress while the LSP is on the standby, the detour at
the ingress is cleaned up and for one-to-one detours a "path tear" is sent for the detour
path. In other words, the detour at the ingress does not protect the standby. If and when the
primary LSP is again successfully re-signaled, the ingress detour state machine will be
restarted.
When the primary fails at the ingress:
The LSP switches to the detour path. If a standby is available then LSP would switch to
standby on expiration of hold-timer. If hold-timer is disabled then switchover to standby
would happen immediately. On successful global revert of primary path, the LSP would
switch back to the primary path.
Admin groups are not taken into account when creating detours for LSPs.
7210 SAS M, T, X, R6, Mxp MPLS Configura-