Cisco ASR 9000 Series Routing Configuration Manual page 205

Implementing BGP
DETAILED STEPS
Command or Action
Step 1
configure
Step 2 router bgp as-number
Example:
RP/0/RSP0/CPU0:router(config)# router
bgp 120
Step 3 address-family { ipv4 | ipv6 } unicast
Example:
RP/0/RSP0/CPU0:router(config-bgp)#
address-family ipv4 unicast
Step 4 maximum-paths { ebgp | ibgp | eibgp }
maximum [ unequal-cost ]
Example:
RP/0/RSP0/CPU0:router(config-bgp-af)#
maximum-paths ebgp 3
Step 5 exit
Example:
RP/0/RSP0/CPU0:router(config-bgp-af)#
exit
Step 6 neighbor ip-address
Example:
RP/0/RSP0/CPU0:router(config-bgp)#
neighbor 10.0.0.0
Purpose
Specifies the autonomous system number and enters the BGP
configuration mode, allowing you to configure the BGP routing process.
Specifies either an IPv4 or IPv6 address family unicast and enters address
family configuration submode.
To see a list of all the possible keywords and arguments for this
command, use the CLI help (?).
Configures the maximum number of parallel routes that BGP installs in
the routing table.
Note
• ebgp maximum : Consider only eBGP paths for multipath.
• ibgp maximum [ unequal-cost ]: Consider load balancing between
iBGP learned paths.
• eibgp maximum : Consider both eBGP and iBGP learned paths
for load balancing. eiBGP load balancing always does unequal-cost
load balancing.
When eiBGP is applied, eBGP or iBGP load balancing cannot be
configured; however, eBGP and iBGP load balancing can coexist.
Exits the current configuration mode.
Configures a CE neighbor. The ip-address argument must be a private
address.
Cisco ASR 9000 Series Aggregation Services Router Routing Configuration Guide, Release 5.3.x
Enabling BGP Unequal Cost Recursive Load Balancing
• Valid values for maximum-paths are 8 for ASR 9000
Ethernet Line Card and 32 for ASR 9000 Enhanced
Ethernet Line Card.
• The ASR 9000 Ethernet Line Card limits the number of
routes to be installed to 8 in the forwarding hardware even
though the maximum-path value configured is more than
8.
175