Cisco ASR 9000 Series Configuration Guide

PurposeCommand or Action
Directs the BGP software to consider a missing MED attribute
in a path as having a value of infinity, making this path the
least desirable path.
bgp bestpath med missing-as-worst
Example:
RP/0/RSP0/CPU0:router(config-bgp)# bgp
bestpath med missing-as-worst
Step 3
Configures the BGP speaker in the specified autonomous
system to compare MEDs among all the paths for the prefix,
bgp bestpath med always
Example:
RP/0/RSP0/CPU0:router(config-bgp)# bgp
bestpath med always
Step 4
regardless of the autonomous system from which the paths
are received.
Enables BGP software to compare MED values for paths
learned from confederation peers.
bgp bestpath med confed
Example:
RP/0/RSP0/CPU0:router(config-bgp)# bgp
bestpath med confed
Step 5
Configures the BGP software to ignore the autonomous system
length when performing best-path selection.
bgp bestpath as-path ignore
Example:
RP/0/RSP0/CPU0:router(config-bgp)# bgp
bestpath as-path ignore
Step 6
Configure the BGP speaker in the autonomous system to
compare the router IDs of similar paths.
bgp bestpath compare-routerid
Example:
RP/0/RSP0/CPU0:router(config-bgp)# bgp
bestpath compare-routerid
Step 7
commit
Step 8
Indicating BGP Back-door Routes
Perform this task to set the administrative distance on an external Border Gateway Protocol (eBGP) route to
that of a locally sourced BGP route, causing it to be less preferred than an Interior Gateway Protocol (IGP)
route.
SUMMARY STEPS
1.
configure
2.
router bgp as-number
3.
address-family { ipv4 | ipv6 } unicast
4.
network { ip-address / prefix-length | ip-address mask } backdoor
5.
commit
Cisco ASR 9000 Series Aggregation Services Router Routing Configuration Guide, Release 5.1.x
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Implementing BGP
Indicating BGP Back-door Routes

Cisco ASR 9000 Series Specifications

General

Series	ASR 9000
Category	Network Router
Modular Design	Yes
Redundancy	Yes (Hardware and Software)
Operating System	Cisco IOS XR
Interfaces/Ports	10G, 40G, 100G, 400G Ethernet
Expansion Slots	Varies by model
Routing Protocol	BGP, OSPF, IS-IS, EIGRP
Management	CLI, SNMP, NETCONF
Power Supply	Redundant
Port Density	Varies by model
Power Supply Options	AC, DC
Memory	Varies by model
Storage	Varies by model
Dimensions	Varies by model
Weight	Varies by model