Table of Contents
Advertisement
MPLS Guide
entropy-label
Syntax
entropy-label {force-disable | inherit | enable}
Context
config>router>mpls>lsp
Description
This command configures the use of entropy labels for an LSP.
If entropy-label is enabled, the entropy label and entropy label indicator (ELI) are inserted in
the label stack. In some cases, this may result in an unsupported label stack depth or large
changes in the label stack depth during the lifetime of an LSP (for example, due to switching
from a primary path with ELC enabled to a secondary path for which the far end has not
signaled ELC).
This command provides local control at the head end of an RSVP LSP over whether an
entropy label is inserted on an LSP by overriding the ELC signaled from the far-end LER, and
control over how the additional label stack depth is accounted for.
By default, the value of entropy-label is inherited from the MPLS level. This command
overrides the default MPLS behavior on a per-LSP basis. For auto LSPs, it can only be
configured in LSP templates of type one-hop-p2p and mesh-p2p.
Under the LSP context, when the value of entropy-label is set to enable, the ingress LER
considers what is signaled from the egress node for ELC when marking the NHLFE as
entropy-label-capable. When the value of entropy-label is set to enable at the LSP level, the
system always marks the LSP as entropy label-capable regardless of the signaled value, in
order to ensure that the potential additional label stack depth is accounted for. In this
scenario, the TTM and NHLFE can be out of synchronization based on what is configured at
the egress node. That is, the application will always account for the entropy label and ELI in
the label stack without taking into consideration the signaled value of the ELC.
When the value of entropy-label changes at either the MPLS level or the LSP level, the new
operational value does not take effect until the LSP is resignaled. A shutdown/no shutdown
command must be performed to enable the new value.
The user can use the clear command or bounce MPLS using the shutdown/no shutdown
command to force the new value to take effect for a large numbers of LSPs.
Default
entropy-label inherit
Parameters
force-disable — the ingress LER will not consider the entropy label and ELI in the label
inherit — the value of entropy-label is inherited from the setting in the MPLS context
enable — the ingress LER will take into consideration what is signaled from the egress
3HE 18686 AAAB TQZZA
stack while sending the information to the TTM and NHLFE. The system will mark the
TTM and NHLFE as ELC not supported, and applications will not insert an entropy
label or entropy label indicator in the label stack.
node for ELC for marking the NHLFE, while the TTM is always marked. Although
applications will only insert the entropy label if the far end signals ELC, the additional
two labels of the entropy label and ELI are always accounted for.
Use subject to Terms available at: www.nokia.com
© 2022 Nokia.
MPLS and RSVP-TE
189
Advertisement
Table of Contents
