Cisco ASR 9000 Series

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
OL-30423-03 85
Implementing BGP
Indicating BGP Back-door Routes