Reference Guide

Intermediate System to Intermediate System (IS-IS) | 831
Parameters
Defaults
Default is Graceful Restart disabled
Command Modes
ROUTER ISIS
Command
History
Usage
Information
A Restart TLV included in every Graceful Restart enabled router’s HELLO PDUs. This enables the
(re)starting as well as the existing ISIS peers to detect the GR capability of the routers on the connected
network. A flag in the Restart TLV contains Restart Request (RR), Restart Acknowledge (RA) and
Suppress Adjacency Advertisement (SA) bit flags.
The ISIS Graceful Restart enabled router can co-exist in mixed topologies where some routers are
Graceful Restart enabled and others are not. For neighbors that are not Graceful Restart enabled, the
restarting router brings up the adjacency per the usual methods.
graceful-restart interval
e
Set the Graceful Restart grace period, the time during which all Graceful Restart attempts are
prevented.
Syntax
graceful-restart interval minutes
To return to the default, use the no graceful-restart interval command.
Parameters
Defaults
5 minutes
Command Modes
ROUTER ISIS
Command
History
graceful-restart t1
e
Set the Graceful Restart wait time before unacknowledged restart requests are generated. This is the
interval before the system sends a Restart Request (an IIH with RR bit set in Restart TLV) until the
CSNP is received from the helping router.
Syntax
graceful-restart t1 {interval seconds | retry-times value}
To return to the default, use the no graceful-restart t1command.
ietf Enter ietf to enable Graceful Restart on the IS-IS router.
Version 8.3.1.0 Introduced on the E-Series
minutes
Range: 1-20 minutes
Default: 5 minutes
Version 8.3.1.0 Introduced on the E-Series