- R3 and R4 must have 5.5.5.5/32 and 6.6.6.6/32 in their BGP/routing table.
Sounds simple..? Well how about you figure it out then :) .. Here is the topology.
Restrictions
- Static routes should not be added anywhere!! In other words, get BGP to work properly.
You should be able to figure out the issues with the following show commands below.
R1#show ip bgp nei 1.1.1.2 advertised-routes
BGP table version is 3, local router ID is 6.6.6.6
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path
*> 5.5.5.5/32 0.0.0.0 0 32768 i
*> 6.6.6.6/32 0.0.0.0 0 32768 i
R2#show ip bgpBGP table version is 3, local router ID is 3.3.3.2 Status codes: s suppressed, d damped, h history, * valid, > best, i - internal, r RIB-failure, S Stale Origin codes: i - IGP, e - EGP, ? - incomplete Network Next Hop Metric LocPrf Weight Path*> 5.5.5.5/32 1.1.1.1 0 0 1 i *> 6.6.6.6/32 1.1.1.1 0 0 1 i
R2#show ip route
1.0.0.0/24 is subnetted, 1 subnets
C 1.1.1.0 is directly connected, FastEthernet1/0
2.0.0.0/24 is subnetted, 1 subnets
C 2.2.2.0 is directly connected, FastEthernet2/0
3.0.0.0/24 is subnetted, 1 subnets
C 3.3.3.0 is directly connected, FastEthernet1/1
5.0.0.0/32 is subnetted, 1 subnets
B 5.5.5.5 [20/0] via 1.1.1.1, 00:10:49
6.0.0.0/32 is subnetted, 1 subnets
B 6.6.6.6 [20/0] via 1.1.1.1, 00:10:49
R2#show run | sec bgp
router bgp 2
no synchronization
bgp log-neighbor-changes
neighbor 1.1.1.1 remote-as 1
neighbor 1.1.1.1 soft-reconfiguration inbound
neighbor 2.2.2.3 remote-as 2
neighbor 2.2.2.3 next-hop-self
neighbor 2.2.2.3 prefix-list adv-r3-out out
neighbor 3.3.3.4 remote-as 4
neighbor 3.3.3.4 prefix-list adv-r4-out out
no auto-summary
R2#show ip prefix-list
ip prefix-list adv-r3-out: 2 entries
seq 10 permit 5.5.5.5/32
seq 20 permit 6.6.6.6/32
ip prefix-list adv-r4-out: 2 entries
seq 10 permit 5.5.5.5/32
seq 20 permit 6.6.6.6/32
R2#show ip bgp 5.5.5.5
BGP routing table entry for 5.5.5.5/32, version 2
Paths: (1 available, best #1, table Default-IP-Routing-Table, not advertised to any peer)
Not advertised to any peer
1, (received & used)
1.1.1.1 from 1.1.1.1 (6.6.6.6)
Origin IGP, metric 0, localpref 100, valid, external, best
Community: no-advertise
R2#show ip bgp 6.6.6.6
BGP routing table entry for 6.6.6.6/32, version 3
Paths: (1 available, best #1, table Default-IP-Routing-Table, not advertised to EBGP peer)
Advertised to update-groups:
2
1, (received & used)
1.1.1.1 from 1.1.1.1 (6.6.6.6)
Origin IGP, metric 0, localpref 100, valid, external, best
Community: no-export
R3#show ip bgp
BGP table version is 2, local router ID is 2.2.2.3
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path
*>i6.6.6.6/32 2.2.2.2 0 100 0 1 i
R3#show run | sec bgp
router bgp 2
no synchronization
bgp log-neighbor-changes
neighbor 2.2.2.2 remote-as 2
no auto-summary
R3#show ip route
2.0.0.0/24 is subnetted, 1 subnets
C 2.2.2.0 is directly connected, FastEthernet1/0
6.0.0.0/32 is subnetted, 1 subnets
B 6.6.6.6 [200/0] via 2.2.2.2, 01:59:56
R4#show run | sec bgp
router bgp 4
no synchronization
bgp log-neighbor-changes
neighbor 3.3.3.2 remote-as 2
neighbor 3.3.3.2 distribute-list block-most-routes-allow-certain in
no auto-summary
R4#show ip bgp summary
BGP router identifier 3.3.3.4, local AS number 4
BGP table version is 1, main routing table version 1
Neighbor V AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down State/PfxRcd
3.3.3.2 4 2 124 124 1 0 0 02:03:05 0
ip access-list standard block-most-routes-allow-certain
permit 5.5.5.5
permit 6.6.6.6
deny 5.5.5.0 0.0.0.255
deny 6.6.6.0 0.0.0.255
R4#show ip route
3.0.0.0/24 is subnetted, 1 subnets
C 3.3.3.0 is directly connected, FastEthernet1/0 - Why is 5.5.5.5/32 NOT in R3's BGP/routing table?
- Why is 5.5.5.5/32 and 6.6.6.6/32 NOT in R4's BGP/routing table?
- What would you do to get this resolved??
Please leave comments...
Can you post the gns3 file please?
ReplyDeletehttps://drive.google.com/folderview?id=0B9lBjpYBzuFoamxtUXlRYmxvN2M&usp=sharing
DeleteHi Arwin,
ReplyDeleteFor me this configuration worked.
R3#sh run | sec bgp
router bgp 2
synchronization
This gave me the output of both the routes in my BGP.
R3#sh ip bg
R3#sh ip bgp
BGP table version is 5, local router ID is 2.2.2.3
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path
*>i5.5.5.5/32 2.2.2.2 0 100 0 1 i
*>i6.6.6.6/32 2.2.2.2 0 100 0 1 i
Also before working on the Troubleshooting part, when i did the configuration on GNS3 based on your template, both these Routes were showing in my BGP table but not in the Routing table.
Once i gave the Sync command as i saw it was an IBGP router for R2, I was able to see both the routes in the routing table.
R3#sh ip route
Codes: 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
Gateway of last resort is not set
2.0.0.0/24 is subnetted, 1 subnets
C 2.2.2.0 is directly connected, FastEthernet0/0
5.0.0.0/32 is subnetted, 1 subnets
B 5.5.5.5 [200/0] via 2.2.2.2, 00:05:20
6.0.0.0/32 is subnetted, 1 subnets
B 6.6.6.6 [200/0] via 2.2.2.2, 00:05:20
My email is arwinr@gmail.com...send me an email and i can tell you how to figure out the issue with just the show commands posted above.
DeleteThank you
R1(config-router)#no neighbor 1.1.1.2 send-community, will solve this.
ReplyDeleteOR
(on R1 again)
access-list 5 permit 5.5.5.5 0.0.0.0
#example of ACL5
access-list 6 permit 6.6.6.6 0.0.0.0
#example of ACL6
neighbor 1.1.1.2 route-map mapName out
#example of neighbor command
route-map mapName
#example of route map
match ip address 5
NO set community no-export #changes
match ip address 6
NO set community no-advertise #changes
Good job!
Delete