Configuring BGP4 Graceful Restart per Neighbor

Note

High availability (HA) requires GR to be enabled.

Enter the configure terminal command to access global configuration mode.
```
SLX # configure terminal
```
Enter the router bgp command to enable BGP routing.
```
SLX (config)# router bgp 
```
Enter the local-as command to configure the autonomous system number (ASN) in which your device resides.
```
SLX (config-bgp-router)# local-as 1000
```
Enter the neighbor ip address remote-as command to add a neighbor.
```
SLX (config-bgp-router)# neighbor 10.11.12.13 remote-as 2
```

Enable Graceful Restart for this IPv4 neighbor.

SLX (config-bgp-router)# neighbor 10.11.12.13 graceful-restart

Enter the address-family ipv4 unicast command to enter IPv4 address-family configuration mode.
```
SLX (config-bgp-router)# address-family ipv4 unicast
```
Do any of the following optional configurations:
- Enter the graceful-restart command and use purge-time parameter to overwrite the default purge-time value.
```
SLX (config-bgp-ipv4u)# graceful-restart purge-time 300
```
- Enter the graceful-restart command and use restart-time parameter to overwrite the default restart-time advertised to graceful restart-capable neighbors.
```
device(config-bgp-ipv4u)# graceful-restart restart-time 180
```
- Enter the graceful-restart command and use stale-routes-time parameter to overwrite the default amount of time that a helper device will wait for an EOR message from a peer.
```
device(config-bgp-ipv4u)# graceful-restart stale-routes-time 100 
```

The following example enables the GR feature. Once enabled, the neighbor with IP address 10.11.12.13 is configured to gracefully restart.

SLX # configure terminal	
SLX (config)# router bgp
SLX (config-bgp-router)# local-as 1
SLX (config-bgp-router)# neighbor 10.11.12.13 remote-as 2
SLX (config-bgp-router)# neighbor 10.11.12.13 graceful-restart

The following example disables the Graceful Restart feature. Once disabled, the neighbor with IP address 10.11.12.13 is no longer configured to gracefully restart.

SLX # configure terminal	
SLX (config)# router bgp
SLX (config-bgp-router)# local-as 1
SLX (config-bgp-router)# neighbor 10.11.12.13 remote-as 2
SLX (config-bgp-router)# neighbor 10.11.12.13 graceful-restart disable

The following example shows the configuration of graceful restart on the BGP peer-group.

SLX # configure terminal
SLX (config)# router bgp
SLX (config-bgp-router)# local-as 1
SLX (config-bgp-router)# neighbor mypeer1 peer-group 
SLX (config-bgp-router)# neighbor mypeer1 remote-as 2 
SLX (config-bgp-router)# neighbor mypeer1 graceful-restart

Use the clear ip bgp neighbor command with the all parameter for the changes to the GR parameters to take effect immediately.