Note Regarding Disabling Bgp4; Bgp4 Parameters - Foundry Networks FESX Manual

NOTE: By default, the Foundry router ID is the IP address configured on the lowest numbered loopback
interface. If the Layer 3 Switch does not have a loopback interface, the default router ID is the lowest numbered IP
interface address configured on the device. For more information or to change the router ID, see "Changing the
Router ID" on page 16-23. If you change the router ID, all current BGP4 sessions are cleared.
FESX424 Router> enable
FESX424 Router# configure terminal
FESX424 Router(config)# router bgp
BGP4: Please configure 'local-as' parameter in order to enable BGP4.
FESX424 Router(config-bgp-router)# local-as 10
FESX424 Router(config-bgp-router)# neighbor 209.157.23.99 remote-as 100
FESX424 Router(config-bgp-router)# write memory
NOTE: When BGP4 is enabled on a Foundry Layer 3 Switch, you do not need to reset the system. The protocol
is activated as soon as you enable it. Moreover, the router begins a BGP4 session with a BGP4 neighbor as soon
as you add the neighbor.

Note Regarding Disabling BGP4

If you disable BGP4, the Layer 3 Switch removes all the running configuration information for the disabled protocol
from the running-config. To restore the BGP4 configuration, you must reload the software to load the configuration
from the startup-config. Moreover, when you save the configuration to the startup-config file after disabling the
protocol, all the configuration information for the disabled protocol is removed from the startup-config file.
The CLI displays a warning message such as the following:
FESX424 Router(config-bgp-router)# no router bgp
router bgp mode now disabled. All bgp config data will be lost when writing to
flash!
If you are testing a BGP4 configuration and are likely to disable and re-enable the protocol, you might want to
make a backup copy of the startup-config file containing the protocol's configuration information. This way, if you
remove the configuration information by saving the configuration after disabling the protocol, you can restore the
configuration by copying the backup copy of the startup-config file onto the flash memory.
NOTE: To disable BGP4 without losing the BGP4 configuration information, remove the local AS (for example, by
entering the no local-as <num> command). In this case, BGP4 retains the other configuration information but is
not operational until you set the local AS again.

BGP4 Parameters

You can modify or set the following BGP4 parameters.
• Optional – Define the router ID. (The same router ID also is used by OSPF.)
• Required – Specify the local AS number.
• Optional – Add a loopback interface for use with neighbors.
• Required – Identify BGP4 neighbors.
• Optional – Change the Keep Alive Time and Hold Time.
• Optional – Change the update timer for route changes.
• Optional – Enable fast external fallover.
• Optional – Specify a list of individual networks in the local AS to be advertised to remote ASs using BGP4.
• Optional – Change the default local preference for routes.
December 2005 © Foundry Networks, Inc.
Configuring BGP4
21 - 7