Nokia 7705 SAR-W Series Manual page 101

MPLS Guide
This command is used to set a limit on the maximum label stack size of the SR-TE
LSP primary path to allow room to insert additional transport, service, and other
labels when packets are forwarded in a particular context.
CLI Syntax:
The max-sr-labels label-stack-size value should be set to account for the desired
maximum label stack of the primary path of the SR-TE LSP. Its range is 1 to 11 and
the default value is 6.
The value in additional-frr-labels labels should be set to account for additional
labels inserted by remote LFA or Topology Independent LFA (TI-LFA) for the backup
next hop of the SR-TE LSP. Its range is 0 to 4 labels with a default value of 1.
The sum of both label values represents the worst-case transport of SR label stack
size for this SR-TE LSP and is populated by MPLS in the TTM such that services and
shortcut applications can check it to decide if a service can be bound or a route can
be resolved to this SR-TE LSP. More details of the label stack size check and
requirements in various services and shortcut applications are provided in
and Shortcut Application SR-TE Label Stack
The maximum label stack supported by the router is discussed in
The maximum label stack is always signaled by the PCC in the PCEP Open object
as part of the SR-PCE-CAPABILITY TLV. It is referred to as the Maximum Stack
Depth (MSD).
In addition, the per-LSP value for the max-sr-labels label-stack-size option, if
configured, is signaled by the PCC to the PCE in the SID Depth value in a METRIC
object for both a PCE-computed LSP and a PCE-controlled LSP. The PCE will
compute and provide the full explicit path with TE links specified. If there is no path
with the number of hops lower than the MSD value or the SID Depth value (if
signaled), a reply with no path will be returned to the PCC.
For a PCC-controlled LSP, if the label stack returned by the TE-DB hop-to-label
translation exceeds the per-LSP maximum SR label stack size, the LSP is brought
down.
3HE 18686 AAAB TQZZA
config>router>mpls>lsp>max-sr-labels label-stack-size
[additional-frr-labels labels]
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