Connectivity Guide

The Local-AS does not prepend the updates with the AS number received from the EBGP peer if you use the no prepend command. If
you do not select no prepend, the default, the Local-AS adds to the rst AS segment in the AS-PATH. If you use an inbound route-map
to prepend the AS-PATH to the update from the peer, the Local-AS adds rst.
If Router B has an inbound route-map applied on Router C to prepend 65001 65002 to the AS-PATH, these events take place on Router B:
• Receive and validate the update.
• Prepend local-as 200 to AS-PATH.
• Prepend 65001 65002 to AS-PATH.
Local-AS prepends before the route map to give the appearance that the update passed through a router in AS 200 before it reaches
Router B.
Congure Border Gateway Protocol
BGP is disabled by default. To enable the BGP process and start to exchange information, assign an AS number and use commands in
ROUTER-BGP mode to congure a BGP neighbor.
BGP neighbor
adjacency changes
All BGP neighbor changes are logged
Fast external fallover Enabled
Graceful restart Disabled
Local preference 100
4-byte AS Enabled
MED 0
Route ap
dampening
parameters
• half-life = 15 minutes
• max-suppress-time = 60 minutes
• reuse = 750
• suppress = 2000
Timers
• keepalive = 60 seconds
• holdtime = 180 seconds
Add-path Disabled
Enable BGP
Before enabling BGP, assign a BGP router ID to the switch using the following command:
• In the ROUTER BGP mode, enter the router-id ip-address command. Where in, ip-address is the IP address corresponding
to a congured L3 interface (physical, loopback, or LAG).
BGP is disabled by default. The system supports one AS number — you must assign an AS number to your device. To establish BGP
sessions and route trac, congure at least one BGP neighbor or peer. In BGP, routers with an established TCP connection are called
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Layer 3