Step 1
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enable
Use this command to enable privileged EXEC mode. Enter your password, if prompted. For example:
Example:
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Step 2
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show
vrf
detail
Use this command to verify that the BGP Best External feature is enabled. The following
show
vrf
detail command output shows that the BGP Best External feature is enabled.
Example:
Router# show vrf detail
VRF test1 (VRF Id = 1); default RD 400:1; default VPNID <not set>
Interfaces:
Se4/0
Address family ipv4 (Table ID = 1 (0x1)):
Export VPN route-target communities
RT:100:1 RT:200:1 RT:300:1
RT:400:1
Import VPN route-target communities
RT:100:1 RT:200:1 RT:300:1
RT:400:1
No import route-map
No export route-map
VRF label distribution protocol: not configured
VRF label allocation mode: per-prefix
Prefix protection with additional path enabled
Address family ipv6 not active.
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Step 3
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show
ip
bgp
ipv4
mdt
all
|
rd
vrf} |
multicast |
tunnel
unicast
or show
ip bgp vpn4
all
rd
route-distinguisher
|
vrf
vrf-name
rib-failure
ip-prefix/length
longer-prefixes]]
network-address
mask
longer-prefixes]]
cidr-only
community
community-list
dampened-paths
filter-list] [flap-statistics
inconsistent-as
neighbors
paths
line]]
peer-group
quote-regexp
regexp] [summary
labels
Use this command to verify that the best external route is advertised. In the command output, the code b indicates a backup path and the code x designates the best external path.
Example:
Router# show ip bgp vpnv4 all
BGP table version is 1104964, local router ID is 10.2.2.2
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
r RIB-failure, S Stale, multipath,
b backup-path, x best-external
Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path
Route Distinguisher: 11:12 (default for vrf blue)
*>i1.0.0.1/32 10.10.3.3 0 200 0 1 ?
* i 10.10.3.3 0 200 0 1 ?
* 10.0.0.1 0 1 ?
*bx 10.0.0.1 0 0 1 ?
* 10.0.0.1 0 1 ?
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Step 4
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show
bgp
vpnv4
unicast
vrf
vrf-name
ip-address
Use this command to verify that the best external route is advertised.
Example:
Router# show bgp vpnv4 unicast vrf vpn1 10.10.10.10
BGP routing table entry for 10:10:10.10.10.10/32, version 10
Paths: (2 available, best #1, table vpn1)
Advertise-best-external
Advertised to update-groups:
1 2
200
10.6.6.6 (metric 21) from 10.6.6.6 (10.6.6.6)
Origin incomplete, metric 0, localpref 200, valid, internal, best
Extended Community: RT:1:1
mpls labels in/out 23/23
200
10.1.2.1 from 10.1.2.1 (10.1.1.1)
Origin incomplete, metric 0, localpref 100, valid,
external, backup/repair, advertise-best-external
Extended Community: RT:1:1 , recursive-via-connected
mpls labels in/out 23/nolabel
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Step 5
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show
ip
route
vrf
vrf-name
repair-paths
ip-address
Use this command to display the repair route.
Example:
Router# show ip route vrf vpn1 repair-paths
Routing Table: vpn1
Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route, H - NHRP
+ - replicated route, % - next hop override
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
B 10.1.1.0/24 [200/0] via 10.6.6.6, 00:38:33
[RPR][200/0] via 10.1.2.1, 00:38:33
B 10.1.1.1/32 [200/0] via 10.6.6.6, 00:38:33
[RPR][200/0] via 10.1.2.1, 00:38:33
10.0.0.0/8 is variably subnetted, 3 subnets, 2 masks
C 10.1.2.0/24 is directly connected, Ethernet0/0
L 10.1.2.2/32 is directly connected, Ethernet0/0
B 10.1.6.0/24 [200/0] via 10.6.6.6, 00:38:33
[RPR][200/0] via 10.1.2.1, 00:38:33
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Step 6
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show
ip
cef
vrf
vrf-name
ip-address
detail
Use this command to display the best external route.
Example:
Router# show ip cef vrf test 10.71.8.164 detail
10.71.8.164/30, epoch 0, flags rib defined all labels
recursive via 10.249.0.102 label 35
nexthop 10.249.246.101 Ethernet0/0 label 25
recursive via 10.249.0.104 label 28,
repair
nexthop 10.249.246.101 Ethernet0/0 label 24
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