Advanced Configuration and Management Guide
3.Click on the plus sign next to BGP in the tree view to expand the list of BGP option links.
4.Click on the General link to display the BGP configuration panel, shown in Figure 10.2 on page
5.Edit the number in the Keep Alive Time field. The Keep Alive Time can be 0 – 65535.
6.Edit the number in the Hold Time field. The Hold Time can be 0 or 3 – 65535 (1 and 2 are not allowed). If you set the Hold Time to 0, the routing switch waits indefinitely for messages from a neighbor without concluding that the neighbor is dead.
NOTE: Generally, you should set the Hold Time to three times the value of the Keep Alive Time.
7.Click the Apply button to apply the changes to the device’s
8.Select the Save link at the bottom of the dialog. Select Yes when prompted to save the configuration change to the
Enabling Fast External Fallover
BGP4 routers rely on KEEPALIVE and UPDATE messages from neighbors to signify that the neighbors are alive. For BGP4 neighbors that are two or more hops away, such messages are the only indication that the BGP4 protocol has concerning the alive state of the neighbors. As a result, if a neighbor dies, the routing switch will wait until the Hold Time expires before concluding that the neighbor is dead and closing its BGP4 session and TCP connection with the neighbor.
The routing switch waits for the Hold Time to expire before ending the connection to a
For directly attached neighbors, the routing switch to immediately senses loss of a connection to the neighbor from a change to the state of the port or interface that connects the routing switch to its neighbor. For directly attached EBGP neighbors, the routing switch can use this information to immediately close the BGP4 session and TCP connection to locally attached neighbors that die.
NOTE: The fast external fallover feature applies only to directly attached EBGP neighbors. The feature does not apply to IBGP neighbors.
If you want to enable the routing switch to immediately close the BGP4 session and TCP connection to locally attached neighbors that die, use either of the following methods.
USING THE CLI
To enable fast external fallover, enter the following command:
To disable fast external fallover again, enter the following command:
Syntax: [no]
USING THE WEB MANAGEMENT INTERFACE
1.Log on to the device using a valid user name and password for
2.Click on the plus sign next to Configure in the tree view to expand the list of configuration options.
3.Click on the plus sign next to BGP in the tree view to expand the list of BGP option links.
4.Click on the General link to display the BGP configuration panel, shown in Figure 10.2 on page
5.Select Disable or Enable next to Fast External Fall Over.
6.Click the Apply button to apply the changes to the device’s
7.Select the Save link at the bottom of the dialog. Select Yes when prompted to save the configuration change to the
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