R3303-HP 6600/HSR6600 Routers Layer 3 - IP Routing Configuration Guide

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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 contains 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 Command Remarks
1. Enter system view.
system-view N/A
2. Enter BGP view.
bgp as-number N/A
3. Configure a confederation ID.
confederation id as-number Not configured by default.
4. Specify peering sub ASs in the
confederation.
confederation peer-as
as-number-list
Not configured by default.
Configuring confederation compatibility
If some other routers in the confederation do not comply with RFC 3065, you must enable confederation
compatibility to allow the router to work with those routers.
To configure confederation compatibility:
Step Command Remarks
1. Enter system view.
system-view N/A
2. Enter BGP view.
bgp as-number N/A
3. Enable compatibility with
routers not compliant with
RFC 3065 in the
confederation.
confederation nonstandard
Optional.
Not enabled by default.
Configuring BGP GR
Graceful Restart (GR) ensures the continuity of packet forwarding when BGP restarts or an
active/standby switchover occurs:
• GR restarter—Graceful restarting router. It must be GR capable.
• GR helper—A neighbor of the GR restarter. It helps the GR restarter to complete the GR process.
NOTE:
A
device can act as a GR restarter and GR helper at the same time.
Following is a GR process:
1. A BGP GR restarter and helper exchange Open messages with GR capability. If both parties have
the GR capability, the session established between them is GR capable.
2. When an active/standby switchover occurs on the GR restarter, the GR restarter does not remove
existing route entries; it still uses these routes for packet forwarding. The GR helper marks all routes