3.13 Configure, verify, and troubleshoot RIPv2 for IPv4 (excluding authentication, filtering, manual summarization, redistribution)

Configuring RIP is very simple. The following commands configure RIP v2 and RIP for each network:

Router(config)#router rip
Router(config-router)#version 2
Router(config-router)#no auto-summary
Router(config-router)#network 192.168.2.0

There is only two “show” commands for RIP:

Router#show ip rip database 
192.168.0.0/24 auto-summary
192.168.0.0/24 directly connected, FastEthernet0/0
192.168.1.0/24 auto-summary
192.168.1.0/24
 [1] via 192.168.0.3, 00:00:09, FastEthernet0/0
192.168.2.0/24 auto-summary
192.168.2.0/24 directly connected, GigabitEthernet4/0
192.168.3.0/24 auto-summary
192.168.3.0/24
 [1] via 192.168.2.2, 00:00:19, GigabitEthernet4/0
Router#

Routing Protocol is "rip"
 Outgoing update filter list for all interfaces is not set
 Incoming update filter list for all interfaces is not set
 Sending updates every 30 seconds, next due in 29 seconds
 Invalid after 180 seconds, hold down 180, flushed after 240
 Redistributing: rip
 Default version control: send version 2, receive version 2
 Interface Send Recv Triggered RIP Key-chain
 FastEthernet0/0 2 2 
 GigabitEthernet4/0 2 2 
 Automatic network summarization is not in effect
 Maximum path: 4
 Routing for Networks:
 192.168.0.0
 192.168.2.0
 Routing Information Sources:
 Gateway Distance Last Update
 192.168.2.2 120 00:00:38
 192.168.0.3 120 00:00:31
 Distance: (default is 120)

To verify RIP check the routing table:

Router#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

C 192.168.0.0/24 is directly connected, FastEthernet0/0
R 192.168.1.0/24 [120/1] via 192.168.0.3, 00:00:24, FastEthernet0/0
C 192.168.2.0/24 is directly connected, GigabitEthernet4/0
R 192.168.3.0/24 [120/1] via 192.168.2.2, 00:00:05, GigabitEthernet4/0
Router#

If routes are missing this could mean:

1. missing network command(s)
2. interface or neighbor down
3. mismatched RIP version
4. ACLs blocking updates
   1. RIP v2 uses the 224.0.0.9 multicast address

To troubleshoot RIPv2 use the debug commands:

Router#debug ip rip events 
RIP event debugging is on
Router#debug ip rip database 
RIP database events debugging is on
Router#
*Apr 21 16:02:04.807: RIP: sending v2 update to 224.0.0.9 via GigabitEthernet4/0 (192.168.2.1)
*Apr 21 16:02:04.807: RIP: Update contains 2 routes
*Apr 21 16:02:04.807: RIP: Update queued
*Apr 21 16:02:04.811: RIP: Update sent via GigabitEthernet4/0
*Apr 21 16:02:13.907: RIP: received v2 update from 192.168.2.2 on GigabitEthernet4/0
*Apr 21 16:02:13.907: RIP-DB: network_update with 192.168.3.0/24 succeeds
*Apr 21 16:02:13.911: RIP-DB: adding 192.168.3.0/24 (metric 1) via 192.168.2.2 on GigabitEthernet4/0 to RIP database
*Apr 21 16:02:13.911: RIP: Update contains 1 routes
*Apr 21 16:02:15.775: RIP: sending v2 update to 224.0.0.9 via FastEthernet0/0 (192.168.0.1)
*Apr 21 16:02:15.775: RIP: Update contains 2 routes
*Apr 21 16:02:15.775: RIP: Update queued
*Apr 21 16:02:15.779: RIP: Update sent via FastEthernet0/0
*Apr 21 16:02:17.587: RIP: received v2 update from 192.168.0.3 on FastEthernet0/0
*Apr 21 16:02:17.587: RIP-DB: network_update with 192.168.1.0/24 succeeds
*Apr 21 16:02:17.591: RIP-DB: adding 192.168.1.0/24 (metric 1) via 192.168.0.3 on FastEthernet0/0 to RIP database