Label Distribution Protocol
434
MPLS Guide
© 2022 Nokia.
Use subject to Terms available at: www.nokia.com
3HE 18686 AAAB TQZZA
5.10.3 Applying Import and Export Policies
Inbound filtering (import policy) allows a route policy to control the label bindings that
an LSR accepts from its peers. An import policy can accept or reject label bindings
received from LDP peers. Label bindings can be filtered based on the following:
• neighbor — match on bindings received from the specified peer
• prefix-list — match on bindings with the specified prefix or prefixes
Outbound filtering (export policy) allows a route policy to control the label bindings
advertised by the LSR to its peers. Label bindings can be filtered based on the
following:
• all — all local subnets by specifying direct as the match protocol
• prefix-list — match on bindings with the specified prefix/prefixes
Import or export policies must already exist before they are applied to LDP. Policies
are configured in the config>router>policy-options context. Refer to the “Route
Policies” section in the 7705 SAR Router Configuration Guide for details.
Use the following CLI syntax to apply import or export policies:
CLI Syntax: config>router>ldp
import policy-name [policy-name...(up to 5 max)]
export policy-name [policy-name...(up to 5 max)]
Example: config>router>ldp
config>router>ldp# import LDP-import
config>router>ldp# export LDP-export
config>router>ldp# exit
config>router#
Note:
• The 7705 SAR supports a specific number of labels, which varies by platform and
software release. If the number of labels is exceeded for a specific protocol (for
example, LDP or RSVP), a log message will appear by default in logs 99 and 100. The
log message states the affected protocol and the label count that was exceeded. For
example: “mpls_label_ilm_helper: XXXX XXX XXXX limit reached max obj count of
YYYY”.
• For the LDP protocol, when the label count is exceeded, LDP sessions will be shut
down and all labels will be removed. To recover the LDP sessions, perform a
shutdown/no shutdown combination of commands in the config>router>ldp
context.
To Next Page
Loading...
Need help?
General
