Configuration Example: OSPF on Pod#4

[Tom4498]

OSPF Areas
10.1.1.0 area 0 frame-relay
10.2.1.0 area 2 R1 on VLAN10
10.3.1.0 area 3 R2 and R3 on VLAN30
10.4.1.0 area 4 R4 and R5 on VLAN 40

R1 has ip ospf priority set to 1 and R2, R3, and R4 have it set to 0. All Routers have a loopback0 with an address of 10.10.10.x where x is the Router number.

R1
router ospf 1
network 10.1.1.0 0.0.0.255 area 0
network 10.2.1.0 0.0.0.255 area 2
neighbor 10.1.1.2
neighbor 10.1.1.3
neighbor 10.1.1.4
int loopback0
ip address 10.10.10.1

R2
router ospf 1
network 10.1.1.0 0.0.0.255 area 0
network 10.3.1.0 0.0.0.255 area 3
neighbor 10.1.1.1
exit
int loopback0
ip address 10.10.10.2 255.255.255.0

R3
router ospf 1
network 10.1.1.0 0.0.0.255 area 0
network 10.4.1.0 0.0.0.255 area 4
neighbor 10.1.1.1
exit
int loopback0
ip address 10.10.10.3 255.255.255.0

R4
router ospf 1
network 10.1.1.0 0.0.0.255 area 0
network 10.4.1.0 0.0.0.255 area 4
neighbor 10.1.1.1
exit
int loopback0
ip address 10.10.10.4 255.255.255.0

R7
router ospf 1
network 10.4.1.0 0.0.0.255 area 4

[Tom4498]

R1#show ip ospf database

OSPF Router with ID (10.10.10.1) (Process ID 1)

Router Link States (Area 0)

Link ID ADV Router Age Seq# Checksum Link count
10.10.10.1 10.10.10.1 188 0x80000002 0x00E8B1 1
10.10.10.2 10.10.10.2 188 0x80000002 0x00E9AC 1
10.10.10.3 10.10.10.3 188 0x80000002 0x00E4AF 1
10.10.10.4 10.10.10.4 188 0x80000002 0x00E5AA 1

Net Link States (Area 0)

Link ID ADV Router Age Seq# Checksum
10.1.1.1 10.10.10.1 188 0x80000001 0x005033

Summary Net Link States (Area 0)

Link ID ADV Router Age Seq# Checksum
10.3.1.0 10.10.10.2 244 0x80000001 0x003FC5
10.4.1.0 10.10.10.4 179 0x80000003 0x0023DC

Router Link States (Area 2)

Link ID ADV Router Age Seq# Checksum Link count
10.10.10.1 10.10.10.1 308 0x80000001 0x0033D1 0

R1#show ip ospf neig

Neighbor ID Pri State Dead Time Address Interface
10.10.10.4 0 FULL/DROTHER 00:01:56 10.1.1.4 Serial0
10.10.10.3 0 FULL/DROTHER 00:01:54 10.1.1.3 Serial0
10.10.10.2 0 FULL/DROTHER 00:01:54 10.1.1.2 Serial0

[Tom4498]

R2#show ip ospf database

OSPF Router with ID (10.10.10.2) (Process ID 1)

Router Link States (Area 0)

Link ID ADV Router Age Seq# Checksum Link count
10.10.10.1 10.10.10.1 358 0x80000002 0x00E8B1 1
10.10.10.2 10.10.10.2 357 0x80000002 0x00E9AC 1
10.10.10.3 10.10.10.3 358 0x80000002 0x00E4AF 1
10.10.10.4 10.10.10.4 358 0x80000002 0x00E5AA 1

Net Link States (Area 0)

Link ID ADV Router Age Seq# Checksum
10.1.1.1 10.10.10.1 358 0x80000001 0x005033

Summary Net Link States (Area 0)

Link ID ADV Router Age Seq# Checksum
10.3.1.0 10.10.10.2 414 0x80000001 0x003FC5
10.4.1.0 10.10.10.4 350 0x80000003 0x0023DC

Router Link States (Area 3)

Link ID ADV Router Age Seq# Checksum Link count
10.10.10.2 10.10.10.2 423 0x80000001 0x008D4C 1

Summary Net Link States (Area 3)

Link ID ADV Router Age Seq# Checksum
10.1.1.0 10.10.10.2 349 0x80000003 0x00715D
10.4.1.0 10.10.10.2 345 0x80000001 0x00B50E
R2# sho ip ospf nei

Neighbor ID Pri State Dead Time Address Interface
10.10.10.1 1 FULL/DR 00:01:42 10.1.1.1 Serial0

[Tom4498]

R2
ip multicast-routing
ip pim rp-address 10.3.1.2
!
interface Ethernet0
ip address 10.3.1.2 255.255.255.0
ip pim sparse-dense-mode
R2#show ip pim rp
Group: 224.0.1.40, RP: 10.3.1.2, next RP-reachable in 00:00:45

R4
ip multicast-routing
ip pim rp-address 10.3.1.2
!
interface Ethernet0
ip address 10.4.1.4 255.255.255.0
ip pim sparse-dense-mode
R4#show ip pim rp
Group: 224.0.1.40, RP: 10.3.1.2, uptime 00:00:34, expires never

I need a command to verify this.

[Tom4498]

R3
bridge 1 protocol ieee
dlsw local-peer peer-id 10.3.1.3
dlsw remote-peer 0 tcp 10.4.1.7
!
interface Ethernet 0
bridge-group 1

R3#show dlsw peer
Peers: state pkts_rx pkts_tx type drops ckts TCP uptime
TCP 10.4.1.7 CONNECT 3 3 conf 0 0 0 00:00:31
Total number of connected peers: 1
Total number of connections: 1




R7
bridge 1 protocol ieee
dlsw local-peer peer-id 10.4.1.7 promiscuous
!
interface Ethernet 0/0
bridge-group 1

R7#show dlsw peer
Peers: state pkts_rx pkts_tx type drops ckts TCP uptime
TCP 10.3.1.3 CONNECT 2 2 prom 0 0 0 00:00:07
Total number of connected peers: 1
Total number of connections: 1

[Tom4498]

AS 65002 - R1, R2, and R3
AS 65004 - R4 and R7
R2 and R4 are running EBGP. R2 is a router reflector for R1 and R3. I am already running OSPF so I decided to leave syncronization on to see what happens with the routes.

R1
router bgp 65002
neighbor 10.10.10.2 remote-as 65002
neighbor 10.10.10.2 update-source Loopback0
network 10.1.1.0 mask 255.255.255.0
network 10.2.1.0 mask 255.255.255.0

R2
router bgp 65002
bgp log-neighbor-changes
network 10.1.1.0 mask 255.255.255.0
network 10.3.1.0 mask 255.255.255.0
neighbor 10.10.10.1 remote-as 65002
neighbor 10.10.10.1 update-source Loopback0
neighbor 10.10.10.1 route-reflector-client
neighbor 10.10.10.3 remote-as 65002
neighbor 10.10.10.3 update-source Loopback0
neighbor 10.10.10.3 route-reflector-client
neighbor 10.10.10.4 remote-as 65004
neighbor 10.10.10.4 update-source Loopback0

R3
router bgp 65002
neighbor 10.10.10.2 remote-as 65002
neighbor 10.10.10.2 update-source Loopback0
network 10.1.1.0 mask 255.255.255.0
network 10.3.1.0 mask 255.255.255.0

R4
router bgp 65004
neighbor 10.10.10.2 remote-as 65002
neighbor 10.10.10.2 update-source Loopback0
neighbor 10.10.10.7 remote-as 65004
neighbor 10.10.10.7 update-source Loopback0
network 10.1.1.0 mask 255.255.255.0
network 10.4.1.0 mask 255.255.255.0

R7
router bgp 65004
neighbor 10.10.10.4 remote-as 65004
neighbor 10.10.10.4 update-source Loopback0
network 10.4.1.0 mask 255.255.255.0

[Tom4498]

I noticed the 10.2.1.0 network was not showing up in ospf. I went back and found out I left the interface on R1 shutdown. I turned it on and it started advertizing. I can see the route on R4.

R4#sh ip route
Codes: C - connected, S - static, I - IGRP, 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, E - EGP
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

10.0.0.0/24 is subnetted, 5 subnets
O IA 10.3.1.0 [110/74] via 10.1.1.2, 00:00:37, Serial0
O IA 10.2.1.0 [110/74] via 10.1.1.1, 00:00:33, Serial0
C 10.1.1.0 is directly connected, Serial0
C 10.10.10.0 is directly connected, Loopback0
C 10.4.1.0 is directly connected, Ethernet0

[Tom4498]

R4#show ip bgp
BGP table version is 3, local router ID is 10.10.10.4
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal
Origin codes: i - IGP, e - EGP, ? - incomplete

Network Next Hop Metric LocPrf Weight Path
*> 10.1.1.0/24 0.0.0.0 0 32768 i
*> 10.4.1.0/24 0.0.0.0 0 32768 i

R7#show ip bgp
BGP table version is 2, local router ID is 10.10.10.7
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
*> 10.4.1.0/24 0.0.0.0 0 32768 i

R7#show 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

10.0.0.0/24 is subnetted, 5 subnets
O IA 10.3.1.0 [110/84] via 10.4.1.4, 00:56:41, Ethernet0/0
O IA 10.2.1.0 [110/84] via 10.4.1.4, 00:03:45, Ethernet0/0
C 10.10.10.0 is directly connected, Loopback0
O IA 10.1.1.0 [110/74] via 10.4.1.4, 00:56:41, Ethernet0/0
C 10.4.1.0 is directly connected, Ethernet0/0

[Tom4498]

I configured md5 authentication and turned off mospf messages. I turned md5 on for the areas on the router.

router ospf 1
ignore lsa mospf
area 0 authentication message-digest
area 2 authentication message-digest
area 3 authentication message-digest
area 4 authentication message-digest
exit
int e 0
ip ospf message-digest-key 1 md5 cisco
exit
int s 0
ip ospf message-digest-key 1 md5 cisco
end
wr mem

I verified that the md5 works with show ip ospf nei.

R1#show ip ospf nei

Neighbor ID Pri State Dead Time Address Interface
10.10.10.4 0 FULL/DROTHER 00:01:42 10.1.1.4 Serial0
10.10.10.3 0 FULL/DROTHER 00:01:40 10.1.1.3 Serial0
10.10.10.2 0 FULL/DROTHER 00:01:41 10.1.1.2 Serial0

[Tom4498]

R1#sh ip bgp summary
BGP router identifier 10.10.10.1, local AS number 65002
BGP table version is 3, main routing table version 3
2 network entries using 194 bytes of memory
2 path entries using 72 bytes of memory
1 BGP path attribute entries using 60 bytes of memory
0 BGP route-map cache entries using 0 bytes of memory
0 BGP filter-list cache entries using 0 bytes of memory
BGP using 326 total bytes of memory
BGP activity 2/0 prefixes, 2/0 paths, scan interval 60 secs

Neighbor V AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down State/PfxRcd
10.10.10.2 4 65002 0 0 0 0 0 never Active

R2#show ip bgp summary
BGP router identifier 10.10.10.2, local AS number 65002
BGP table version is 3, main routing table version 3
2 network entries using 194 bytes of memory
2 path entries using 72 bytes of memory
1 BGP path attribute entries using 60 bytes of memory
0 BGP route-map cache entries using 0 bytes of memory
0 BGP filter-list cache entries using 0 bytes of memory
BGP using 326 total bytes of memory
BGP activity 2/0 prefixes, 2/0 paths, scan interval 60 secs

Neighbor V AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down State/PfxRcd
10.10.10.1 4 65002 0 0 0 0 0 never Active
10.10.10.3 4 65002 0 0 0 0 0 never Active
10.10.10.4 4 65004 0 0 0 0 0 never Active

Active is not good. I noticed that I made a mistake taking the loopback and switched to the frame-relay ips.

I took out the update-source option on R2 and R3 and it came up...

R2#
01:20:31: %SYS-5-CONFIG_I: Configured from console by consolewr mem
Building configuration...
[OK]
R2#show ip bgp sum
01:20:54: %BGP-5-ADJCHANGE: neighbor 10.1.1.3 Up mary
BGP router identifier 10.10.10.2, local AS number 65002
BGP table version is 3, main routing table version 3
2 network entries using 194 bytes of memory
4 path entries using 144 bytes of memory
2 BGP path attribute entries using 120 bytes of memory
0 BGP route-map cache entries using 0 bytes of memory
0 BGP filter-list cache entries using 0 bytes of memory
BGP using 458 total bytes of memory
BGP activity 2/0 prefixes, 4/0 paths, scan interval 60 secs

Neighbor V AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down State/PfxRcd
10.1.1.1 4 65002 0 0 0 0 0 never Active
10.1.1.3 4 65002 5 5 3 0 0 00:00:02 2
10.1.1.4 4 65004 0 0 0 0 0 never Active


R1#sh ip bgp summary
BGP router identifier 10.10.10.1, local AS number 65002
BGP table version is 4, main routing table version 4
3 network entries using 291 bytes of memory
4 path entries using 144 bytes of memory
2 BGP path attribute entries using 120 bytes of memory
0 BGP route-map cache entries using 0 bytes of memory
0 BGP filter-list cache entries using 0 bytes of memory
BGP using 555 total bytes of memory
BGP activity 3/0 prefixes, 4/0 paths, scan interval 60 secs

Neighbor V AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down State/PfxRcd
10.1.1.2 4 65002 5 5 3 0 0 00:00:01 2
R1#
01:26:18: %BGP-5-ADJCHANGE: neighbor 10.1.1.2 Up

[Tom4498]

R7#sh ip bgp summary
BGP router identifier 10.10.10.7, local AS number 65004
BGP table version is 2, main routing table version 2
1 network entries using 101 bytes of memory
1 path entries using 48 bytes of memory
1 BGP path attribute entries using 60 bytes of memory
0 BGP route-map cache entries using 0 bytes of memory
0 BGP filter-list cache entries using 0 bytes of memory
BGP using 209 total bytes of memory
BGP activity 1/0 prefixes, 1/0 paths, scan interval 60 secs

Neighbor V AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down State/PfxRcd
10.1.1.4 4 65004 0 0 0 0 0 never Active
R7#clear ip bgp *
R7#sh ip bgp summary
BGP router identifier 10.10.10.7, local AS number 65004
BGP table version is 1, main routing table version 1

Neighbor V AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down State/PfxRcd
10.1.1.4 4 65004 0 0 0 0 0 never Idle

[Tom4498]

It looks like when you clear bgp it bounces back to idle and then active if you have a problem.

R1#sh ip bgp summar
BGP router identifier 10.10.10.1, local AS number 65002
BGP table version is 4, main routing table version 4
3 network entries using 291 bytes of memory
4 path entries using 144 bytes of memory
2 BGP path attribute entries using 120 bytes of memory
0 BGP route-map cache entries using 0 bytes of memory
0 BGP filter-list cache entries using 0 bytes of memory
BGP using 555 total bytes of memory
BGP activity 3/0 prefixes, 4/0 paths, scan interval 60 secs

Neighbor V AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down State/PfxR
10.1.1.2 4 65002 12 12 4 0 0 00:07:12 2
R1#sh ip bgp
BGP table version is 4, local router ID is 10.10.10.1
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal
Origin codes: i - IGP, e - EGP, ? - incomplete

Network Next Hop Metric LocPrf Weight Path
* i10.1.1.0/24 10.1.1.2 0 100 0 i
*> 0.0.0.0 0 32768 i
*> 10.2.1.0/24 0.0.0.0 0 32768 i
*>i10.3.1.0/24 10.1.1.2 0 100 0 i


R2#show ip bgp
BGP table version is 4, local router ID is 10.10.10.2
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal
Origin codes: i - IGP, e - EGP, ? - incomplete

Network Next Hop Metric LocPrf Weight Path
* i10.1.1.0/24 10.1.1.1 0 100 0 i
* i 10.1.1.3 0 100 0 i
*> 0.0.0.0 0 32768 i
*>i10.2.1.0/24 10.1.1.1 0 100 0 i
* i10.3.1.0/24 10.1.1.3 0 100 0 i
*> 0.0.0.0 0 32768 i
R2#sh p bgp summary
^
% Invalid input detected at '^' marker.

R2#sh ip bgp summary
BGP router identifier 10.10.10.2, local AS number 65002
BGP table version is 4, main routing table version 4
3 network entries using 291 bytes of memory
6 path entries using 216 bytes of memory
2 BGP path attribute entries using 120 bytes of memory
0 BGP route-map cache entries using 0 bytes of memory
0 BGP filter-list cache entries using 0 bytes of memory
BGP using 627 total bytes of memory
BGP activity 3/0 prefixes, 6/0 paths, scan interval 60 secs

Neighbor V AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down State/PfxRcd
10.1.1.1 4 65002 13 13 4 0 0 00:08:38 2
10.1.1.3 4 65002 18 19 4 0 0 00:13:09 2
10.1.1.4 4 65004 0 0 0 0 0 never Active


Even though R2 and R4 are on the same network, they are connected over frame-relay through R1 acting as a hub. I add bgp-multihop and got this on R2...

R2#sh ip bgp summar
BGP router identifier 10.10.10.2, local AS number 65002
BGP table version is 4, main routing table version 4
3 network entries using 291 bytes of memory
6 path entries using 216 bytes of memory
2 BGP path attribute entries using 120 bytes of memory
0 BGP route-map cache entries using 0 bytes of memory
0 BGP filter-list cache entries using 0 bytes of memory
BGP using 627 total bytes of memory
BGP activity 3/0 prefixes, 6/0 paths, scan interval 60 secs

Neighbor V AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down State/PfxRcd
10.1.1.1 4 65002 16 16 4 0 0 00:11:05 2
10.1.1.3 4 65002 20 21 4 0 0 00:15:36 2
10.1.1.4 4 65004 0 1 0 0 0 never OpenSent