R0106-HP MSR Router Series Layer 3 - IP Routing Command Reference(V7)

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Usage guidelines
Graceful Restart (GR) ensures continuous forwarding when BGP restarts or an active/standby switchover
occurs.
BGP peers exchange Open messages containing GR information. If both parties have GR capability,
they establish a GR-capable session.
After you execute this command, the device reestablishes BGP sessions.
Examples
# Enable Graceful Restart capability for BGP process 100.
<Sysname> system-view
[Sysname] bgp 100
[Sysname-bgp] graceful-restart
Related commands
• graceful-restart timer restart
• graceful-restart timer wait-for-rib
graceful-restart timer restart
Use graceful-restart timer restart to configure the GR timer.
Use undo graceful-restart timer restart to restore the default.
Syntax
graceful-restart timer restart timer
undo graceful-restart timer restart
Default
The GR timer is 150 seconds.
Views
BGP view
Predefined user roles
network-admin
Parameters
timer: Specifies the GR time in the range of 3 to 600 seconds.
Usage guidelines
The GR restarter sends the GR timer to the GR helper in an Open message. When the GR helper detects
that an active/standby switchover or a BGP restart occurred on the GR restarter, the GR helper does the
following:
• Marks all routes learned from the GR restarter as stale.
• Starts the GR timer.
• If no BGP session is established before the GR timer expires, the GR helper removes the stale routes.
Before you configure this command, enable the BGP GR capability.
To apply a new GR timer, you must reestablish BGP sessions.