•
Route Filtering for inbound and outbound routes
•
Route redistribution and route-maps
•
Support for BGP communities and extended communities in route maps
•
Local preference for IPv4 and IPv6 (IBGP peers)
IP pool routes and loopback routes are advertised in the BGP domain in the following ways:
•
Through BGP Configuration Mode
redistribution
commands, all or some of the connected routes are
redistributed into the BGP domain. (IP pool and loopback routes are present in the IP routing table as
connected routes.) The
network routemap
command provides the flexibility to change many BGP
attributes.
•
Through the BGP Configuration Mode
network
commands, connected routes are explicitly configured
for advertisement into the BGP domain. The
network routemap
command provides the flexibility to
change many BGP attributes. Refer to the
BGP Configuration Mode Commands
chapter of the
Command
Line Interface Reference
for details on these commands.
If a BGP task restarts because of a processing card failure, a migration, a crash, or the removal of a
processing card, all peering session and route information is lost.
Important
Configuring BGP
This section describes how to configure and enable basic BGP routing support in the system.
config
context context_name
router bgp AS_number
neighbor ip_address remote-as AS_num
Notes:
•
A maximum of 64 BGP peers are supported per context.
•
Save your configuration as described in the
Verifying and Saving Your Configuration
chapter.
Redistributing Routes Into BGP (Optional)
Redistributing routes into BGP simply means that any routes from another protocol that meet a specified
criterion, such as a route type, or a rule within a route-map, are redistributed through the BGP protocol to all
BGP areas. This is an optional configuration.
config
context context_name
router bgp as_number
redistribute bgp { bgp | connected | static } [ metric metric_value ] [ metric-type { 1 | 2 } ]
[ route-map route_map_name ]
Notes:
ASR 5500 System Administration Guide, StarOS Release 21.5
216
Routing
Configuring BGP