Scenarios - Juniper JUNOSE SOFTWARE FOR E SERIES 11.3.X - BGP AND MPLS CONFIGURATION GUIDE 2010-10-12 Configuration Manual

Copyright © 2010, Juniper Networks, Inc.
Use to set the maximum time BGP waits to receive an End-of-RIB marker from the
specified restarted peer or peer group before flushing all remaining stale routes from
that peer. The timer begins when BGP recognizes that the peer session has gone down.
This command prevents an excessive delay in BGP reconvergence due to a peer that
brings a session back up but is slow to send fresh routes.
Specify an interval longer than the restart time.
This command takes effect immediately and automatically bounces the session.
Example
host1(config-router)#neighbor graceful-restart stalepaths-time 480
Use the no version to restore the default value, 360 seconds.
See neighbor graceful-restart stalepaths-time.
Configuring Hold Timers for Successful Graceful Restart in Scaled Scenarios
In a scaled environment, we recommend that you increase the hold timers for the following
protocols to appropriate values, based on the level of complexity of the network and
scaling settings, so as to enable graceful restart to be completed successfully.
BGP
IS-IS
LDP
OSPF
RSVP
Consider a scenario in which a provider edge router, PE1, at one side of the service provider
core is connected to a provider core router, P, which is a label-switched router (LSR) that
carries traffic for the VPN tunnel. The core router, P, is connected to another provider
edge router, PE2, which provides egress from the VPN. Both PE1 and PE2 routers
communicate with customer sites through a direct connection to a customer edge (CE)
device that sits at the edge of the customer site.
PE1 is configured for graceful restart and PE2 functions as the helper node, and each PE
router is configured with 1500 VRFs and 1500 adjacencies. In such an environment, you
need to perform the following steps:
On PE1, which is the restarting router, use the hello hold-time command in LDP Profile
1.
Configuration mode to modify the period for which an LSR maintains link hello records
before another link hello is sent as 90 seconds.
host1(config)#mpls ldp interface profile ldp1
host1(config-ldp)#hello hold-time 90
On the interface that connects PE1 to the core router, P, use the isis hello-interval
2.
command in Interface Configuration mode to set the frequency at which the router
sends hello packets on the specified interface as 30 seconds.
host1(config-if)#isis hello-interval 30
Chapter 1: Configuring BGP Routing
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