Connectivity Guide

4 Enable peer listening and enter the maximum dynamic peers count in ROUTER-BGP-TEMPLATE mode (1 to 4294967295).
listen neighbor ip-address limit
Only after the peer template responds to an OPEN message sent on the subnet does the state of its BGP change to ESTABLISHED. After
the peer template is ESTABLISHED, the peer template is the same as any other peer template, see Peer templates.
If you do not congure a BGP device in Peer-Listening mode, a session with a dynamic peer comes up. Passwords are not supported on
BGPv4/v6 dynamic peers.
Congure passive peering
OS10(config)# router bgp 10
OS10(conf-router-bgp-10)# template bgppg
OS10(conf-router-template)# remote-as 100
OS10(conf-router-template)# listen 32.1.0.0/8 limit 10
Local AS
During BGP network migration, you can maintain existing AS numbers. Recongure your routers with the new information to disable after
the migration. Network migration is not supported on passive peer templates. You must congure Peer templates before assigning it to an
AS.
1 Enter a neighbor IP address, A.B.C.D, in ROUTER-BGP mode.
neighbor ip-address
2 Enter a local-as number for the peer, and the AS values not prepended to announcements from the neighbors in ROUTER-
NEIGHBOR mode (1 to 4294967295).
local-as as number [no prepend]
3 Return to ROUTER-BGP mode.
exit
4 Enter a template name to assign to the peer-groups in ROUTER-BGP mode. A maximum of 16 characters.
template template-name
5 Enter a local-as number for the peer in ROUTER-TEMPLATE mode.
local-as as number [no prepend]
6 Add a remote AS in ROUTER-TEMPLATE mode (1 to 65535 for 2 bytes, 1 to 4294967295 for 4 bytes).
remote-as as-number
Allow external routes from neighbor
OS10(config)# router bgp 10
OS10(conf-router-bgp-10)# neighbor 32.1.1.2
OS10(conf-router-neighbor)# local-as 50
OS10(conf-router-neighbor)# exit
OS10(conf-router-bgp-10)# template bgppg1
OS10(conf-router-template)# fall-over
OS10(conf-router-template)# local-as 400
OS10(conf-router-template)# remote-as 102
Local AS number disabled
OS10(config)# router bgp 102
OS10(conf-router-bgp-102)# neighbor 32.1.1.2
OS10(conf-router-neighbor)# no local-as 100
450
Layer 3