Configuring Bgp Gr - HP 6125XLG Configuration Manual

A confederation contains sub-ASs. In each sub-AS, IBGP peers are fully meshed. Sub-ASs establish EBGP
connections in between.
Configuring a BGP confederation
After you split an AS into multiple sub-ASs, configure a router in a sub-AS as follows:
1. Enable BGP and specify the AS number of the router. For more information, see
2. Specify the confederation ID. From an outsider's perspective, the sub-ASs of the confederation is
a single AS, which is identified by the confederation ID.
3. If the router needs to establish EBGP connections to other sub-ASs, you must specify the peering
sub-ASs in the confederation.
A confederation can contain a maximum of 32 sub-ASs. The AS number of a sub-AS is effective only in
the confederation.
To configure a BGP confederation:
Step
1. Enter system view.
2. Enter BGP view.
Configure a confederation ID.
3.
4. Specify peering sub-ASs in the
confederation.
Configuring confederation compatibility
If any routers in the confederation do not comply with RFC 3065, enable confederation compatibility to
allow the router to work with those routers.
To configure confederation compatibility:
Step
1. Enter system view.
2. Enter BGP view.
3. Enable confederation
compatibility.

Configuring BGP GR

GR ensures forwarding continuity when BGP restarts or an active/standby switchover occurs.
Two routers are required to complete a GR process. The following are router roles in a GR process.
GR Restarter—Performs GR upon a BGP restart or active/standby switchover.
•
• GR Helper—Helps the GR Restarter to complete the GR process.
A device can act as a GR Restarter and GR Helper at the same time.
BGP GR works as follows:
Command
system-view
bgp as-number
confederation id as-number
confederation peer-as
as-number-list
Command
system-view
bgp as-number
confederation nonstandard
220
"Enabling
Remarks
N/A
N/A
By default, no confederation ID is
configured.
By default, no peering sub-AS is
specified.
Remarks
N/A
N/A
By default, confederation
compatibility is disabled.
BGP."