Mac-Flush - Juniper EX9200 Features Manual

VPLS Feature Guide for EX9200 Switches

mac-flush

Syntax
Hierarchy Level
Release Information
Description
136
mac-flush [ explicit-mac-flush-message-options ];
[edit logical-systems logical-system-name routing-instances routing-instance-name protocols
vpls],
[edit logical-systems logical-system-name routing-instances routing-instance-name protocols
vpls mesh-group mesh-group-name],
[edit routing-instances routing-instance-name protocols vpls],
[edit routing-instances routing-instance-name protocols vpls mesh-group mesh-group-name]
Statement introduced in Junos OS Release 10.0.
Enable media access control (MAC) flush processing for the virtual private LAN service
(VPLS) routing instance or for the mesh group under a VPLS routing instance. MAC flush
processing removes MAC addresses from the MAC address database that have been
learned dynamically. With the dynamically learned MAC addresses removed, MAC address
convergence requires less time to complete.
For certain cases where MAC flush processing is not initiated by default, you can also
specify explicit-mac-flush-message-options
explicit MAC flush messages. To configure the router to send explicit MAC flush messages
under specific conditions, include
NOTE: In the VPLS documentation, the word router in terms such as PE router
is used to refer to any device that provides routing functions.
In certain cases, BGP updates sent by the provider edge (PE) device are delayed for 1 to
5 seconds.
This happens when all of the following condtions are true:
BGP-based VPLS multihoming sites are configured.
The statement is included in the configuration.

mac-flush

a non-minimum designated-forwarder site (site-x, for example) transitions to
non-designated-forwarder status
The BGP update being delayed corresponds to the explicit-MAC flush notification message
sent by site-x's PE device (PE2, for example). This BGP update message is not deferred
if the designated-forwarder status is lost due to a locally-triggered event (for example,
a local attachment-circuit interface going down). In other words, BGP update messages
are deferred (in Device PE2) only when the designated-forwarder state is lost due to
external events taking place in remote PE devices that also hold site-x (for example, in
PE1). Suppose, for example, that Device PE1 is the default designated-forwarder with
site-x's local interface in the DOWN state. Device PE2 defers BGP update message after
Device PE1's local interface comes back to the UP state.
that additionally configure the router to send
explicit-mac-flush-message-options
Copyright © 2016, Juniper Networks, Inc.
with the statement.