Redistribution between RIP and OSPF..RIP routes disappear..

From: WorkerBee (ciscobee@gmail.com)
Date: Thu Apr 26 2007 - 13:25:39 ART


Anyone can highlight why a router (Rack1SW1) doing 2-way redistribution between
RIP and OSPF within the same router will cause me to loose all
my RIP learned routes from BB3 in the local routing table?

[BB3] -- RIP -- [Rack1SW1] -- OSPF -- [R3]

The only fix is to set RIP AD = 109 (less than OSPF AD) but why it happen??

Is it because the redistribute RIP routes appear as route feedback back to
OSPF as Type 5 LSA and being AD = 110, it replaced my RIP routes?

(Rack1SW1)

                Type-5 AS External Link States

Link ID ADV Router Age Seq# Checksum Tag
30.0.0.0 150.1.2.2 459 0x80000001 0x00F2F3 0
30.1.0.0 150.1.2.2 459 0x80000001 0x00E6FE 0
30.2.0.0 150.1.2.2 459 0x80000001 0x00DA0A 0
30.3.0.0 150.1.2.2 459 0x80000001 0x00CE15 0
31.0.0.0 150.1.2.2 459 0x80000001 0x00E5FF 0
31.1.0.0 150.1.2.2 459 0x80000001 0x00D90B 0
31.2.0.0 150.1.2.2 459 0x80000001 0x00CD16 0
31.3.0.0 150.1.2.2 459 0x80000001 0x00C121 0

############ Before 2-way redistribution ##################

Rack1SW1#show ip route rip
     31.0.0.0/16 is subnetted, 4 subnets
R 31.3.0.0 [120/1] via 204.12.1.254, 00:00:12, Vlan73
R 31.2.0.0 [120/1] via 204.12.1.254, 00:00:12, Vlan73
R 31.1.0.0 [120/1] via 204.12.1.254, 00:00:12, Vlan73
R 31.0.0.0 [120/1] via 204.12.1.254, 00:00:12, Vlan73
     30.0.0.0/16 is subnetted, 4 subnets
R 30.2.0.0 [120/1] via 204.12.1.254, 00:00:12, Vlan73
R 30.3.0.0 [120/1] via 204.12.1.254, 00:00:12, Vlan73
R 30.0.0.0 [120/1] via 204.12.1.254, 00:00:12, Vlan73
R 30.1.0.0 [120/1] via 204.12.1.254, 00:00:12, Vlan73
Rack1SW1#show ip route rip

############ After 2-way redistribution ##################

router ospf 1
 router-id 150.1.7.7
 log-adjacency-changes
 redistribute rip subnets
 network 150.1.7.7 0.0.0.0 area 37
 network 152.1.37.7 0.0.0.0 area 37
!
router rip
 version 2
 redistribute ospf 1 metric 1
 network 204.12.1.0
 no auto-summary

Rack1SW1#show ip route rip

<blank - no rip routes>

And I learned the original RIP routes from my downstream OSPF router.

O E2 31.3.0.0 [110/20] via 152.1.37.3, 00:04:52, Vlan37
O E2 31.2.0.0 [110/20] via 152.1.37.3, 00:04:52, Vlan37
O E2 31.1.0.0 [110/20] via 152.1.37.3, 00:04:52, Vlan37
O E2 31.0.0.0 [110/20] via 152.1.37.3, 00:04:52, Vlan37

O E2 30.2.0.0 [110/20] via 152.1.37.3, 00:04:53, Vlan37
O E2 30.3.0.0 [110/20] via 152.1.37.3, 00:04:53, Vlan37
O E2 30.0.0.0 [110/20] via 152.1.37.3, 00:04:53, Vlan37
O E2 30.1.0.0 [110/20] via 152.1.37.3, 00:04:53, Vlan37



This archive was generated by hypermail 2.1.4 : Tue May 01 2007 - 08:28:38 ART