R0106-HP MSR Router Series Layer 3 - IP Routing Configuration Guide(V7)
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{ Control the route convergence speed.
If routing information exchange is not completed within the time, the GR restarter does not receive
new routes. Instead, the GR restarter updates its routing table and forwarding table with the BGP
routes already learned to complete BGP route convergence. The GR helper removes the stale
routes.
Follow these guidelines when you configure BGP GR:
• The End-Of-RIB indicates the end of route updates.
• The maximum time to wait for the End-of-RIB marker configured on the local end is not advertised
to the peer. It controls the time for the local end to receive updates from the peer.
Perform the following configuration on the GR restarter and GR helper.
To configure BGP GR:
Ste
p
Command
Remarks
1. Enter system view.
system-view N/A
2. Enter BGP view.
bgp as-number N/A
3. Enable GR capability for BGP.
graceful-restart
By default, GR capability is
disabled for BGP.
4. Configure the GR timer.
graceful-restart timer restart
timer
The default setting is 150 seconds.
The time that a peer waits to
reestablish a session must be less
than the hold time.
5. Configure the maximum time to
wait for the End-of-RIB marker.
graceful-restart timer
wait-for-rib timer
The default setting is 180 seconds.
Configuring BGP NSR
The following matrix shows the feature and hardware compatibility:
Hardware BGP NSR
com
p
atibilit
y
MSR2000 No
MSR3000 No
MSR4000 Yes
BGP nonstop routing (NSR) ensures continuous routing by synchronizing BGP state and data information
from the active BGP process to the standby BGP process. The standby BGP process can seamlessly take
over all services when the active process fails in one of the following situations:
• The active BGP process restarts.
• The MPU that runs the active BGP process fails.
• An ISSU is performed on the MPU that runs the active BGP process.
GR and NSR have the following differences:
• To implement NSR, the device must have at least two MPUs because the active and standby BGP
processes run on different MPUs. To implement GR, the device only needs to have one MPU.