Im doing a RIPv2 LAB on my gear and something weird is happening with auto-summary.
This is the scenario:
And these are the routing tables:
auto-summary OFF:[SIZE=1]WEST#sh ip route[/SIZE]
[SIZE=1]Gateway of last resort is not set[/SIZE]
[SIZE=1]
[/SIZE]
[SIZE=1]C 172.16.0.0/16 is directly connected, FastEthernet0/0[/SIZE]
[SIZE=1] 10.0.0.0/30 is subnetted, 4 subnets[/SIZE]
[SIZE=1]R 10.1.1.8 [120/1] via 10.1.1.13, 00:00:06, Serial0/1[/SIZE]
[SIZE=1]C 10.1.1.12 is directly connected, Serial0/1[/SIZE]
[SIZE=1]R 10.1.1.0 [120/2] via 10.1.1.13, 00:00:06, Serial0/1[/SIZE]
[SIZE=1]R 10.1.1.4 [120/1] via 10.1.1.13, 00:00:06, Serial0/1[/SIZE]
[SIZE=1]R 192.168.1.0/24 [120/2] via 10.1.1.13, 00:00:06, Serial0/1[/SIZE]
[SIZE=1]NORTH#sh ip route[/SIZE]
[SIZE=1]Gateway of last resort is not set[/SIZE]
[SIZE=1]
[/SIZE]
[SIZE=1]R 172.16.0.0/16 [120/2] via 10.1.1.9, 00:00:14, Serial0/0[/SIZE]
[SIZE=1] 10.0.0.0/30 is subnetted, 4 subnets[/SIZE]
[SIZE=1]C 10.1.1.8 is directly connected, Serial0/0[/SIZE]
[SIZE=1]R 10.1.1.12 [120/1] via 10.1.1.9, 00:00:14, Serial0/0[/SIZE]
[SIZE=1]C 10.1.1.0 is directly connected, Serial0/2[/SIZE]
[SIZE=1]R 10.1.1.4 [120/1] via 10.1.1.2, 00:00:02, Serial0/2[/SIZE]
[SIZE=1] [120/1] via 10.1.1.9, 00:00:14, Serial0/0[/SIZE]
[SIZE=1]R 192.168.1.0/24 [120/1] via 10.1.1.2, 00:00:02, Serial0/2[/SIZE]
[SIZE=1]HQ#sh ip route[/SIZE]
[SIZE=1]Gateway of last resort is not set[/SIZE]
[SIZE=1]
[/SIZE]
[SIZE=1]R 172.16.0.0/16 [120/1] via 10.1.1.14, 00:00:08, Serial0/0[/SIZE]
[SIZE=1] 10.0.0.0/30 is subnetted, 4 subnets[/SIZE]
[SIZE=1]C 10.1.1.8 is directly connected, Serial0/1[/SIZE]
[SIZE=1]C 10.1.1.12 is directly connected, Serial0/0[/SIZE]
[SIZE=1]R 10.1.1.0 [120/1] via 10.1.1.10, 00:00:01, Serial0/1[/SIZE]
[SIZE=1] [120/1] via 10.1.1.6, 00:00:01, Serial0/2[/SIZE]
[SIZE=1]C 10.1.1.4 is directly connected, Serial0/2[/SIZE]
[SIZE=1]R 192.168.1.0/24 [120/1] via 10.1.1.6, 00:00:01, Serial0/2[/SIZE]
[SIZE=1]SOUTH#sh ip route[/SIZE]
[SIZE=1]Gateway of last resort is not set[/SIZE]
[SIZE=1]
[/SIZE]
[SIZE=1]R 172.16.0.0/16 [120/2] via 10.1.1.5, 00:00:18, Serial0/1[/SIZE]
[SIZE=1] 10.0.0.0/30 is subnetted, 4 subnets[/SIZE]
[SIZE=1]R 10.1.1.8 [120/1] via 10.1.1.1, 00:00:13, Serial0/2[/SIZE]
[SIZE=1] [120/1] via 10.1.1.5, 00:00:18, Serial0/1[/SIZE]
[SIZE=1]R 10.1.1.12 [120/1] via 10.1.1.5, 00:00:18, Serial0/1[/SIZE]
[SIZE=1]C 10.1.1.0 is directly connected, Serial0/2[/SIZE]
[SIZE=1]C 10.1.1.4 is directly connected, Serial0/1[/SIZE]
[SIZE=1]C 192.168.1.0/24 is directly connected, FastEthernet0/0[/SIZE]
auto-summary ON:
[SIZE=1]WEST#sh ip route
[/SIZE][SIZE=1]Gateway of last resort is not set[/SIZE][SIZE=1]
[/SIZE]
[SIZE=1]C 172.16.0.0/16 is directly connected, FastEthernet0/0[/SIZE]
[SIZE=1] 10.0.0.0/30 is subnetted, 4 subnets[/SIZE]
[SIZE=1]R 10.1.1.8 [120/1] via 10.1.1.13, 00:00:20, Serial0/1[/SIZE]
[SIZE=1]C 10.1.1.12 is directly connected, Serial0/1[/SIZE]
[SIZE=1]R 10.1.1.0 [120/2] via 10.1.1.13, 00:00:20, Serial0/1[/SIZE]
[SIZE=1]R 10.1.1.4 [120/1] via 10.1.1.13, 00:00:20, Serial0/1[/SIZE]
[COLOR=#ff0000][SIZE=1]R 192.168.1.0/24 [120/1] via 10.1.1.13, 00:00:20, Serial0/1[/SIZE][/COLOR]
[SIZE=1]NORTH#sh ip route
[/SIZE][SIZE=1]Gateway of last resort is not set[/SIZE][SIZE=1]
[/SIZE]
[COLOR=#ff0000][SIZE=1]R 172.16.0.0/16 [120/1] via 10.1.1.9, 00:00:14, Serial0/0[/SIZE][/COLOR]
[SIZE=1] 10.0.0.0/30 is subnetted, 4 subnets[/SIZE]
[SIZE=1]C 10.1.1.8 is directly connected, Serial0/0[/SIZE]
[SIZE=1]R 10.1.1.12 [120/1] via 10.1.1.9, 00:00:14, Serial0/0[/SIZE]
[SIZE=1]C 10.1.1.0 is directly connected, Serial0/2[/SIZE]
[SIZE=1]R 10.1.1.4 [120/1] via 10.1.1.2, 00:00:12, Serial0/2[/SIZE]
[SIZE=1] [120/1] via 10.1.1.9, 00:00:14, Serial0/0[/SIZE]
[SIZE=1]R 192.168.1.0/24 [120/1] via 10.1.1.2, 00:00:12, Serial0/2[/SIZE]
[SIZE=1]HQ#sh ip route
[/SIZE][SIZE=1]Gateway of last resort is not set[/SIZE]
[COLOR=#ff0000][SIZE=1]R 172.16.0.0/16 [120/1] via 10.1.1.14, 00:00:14, Serial0/0[/SIZE]
[SIZE=1] [120/1] via 10.1.1.6, 00:00:16, Serial0/2[/SIZE][/COLOR]
[SIZE=1] 10.0.0.0/30 is subnetted, 4 subnets[/SIZE]
[SIZE=1]C 10.1.1.8 is directly connected, Serial0/1[/SIZE]
[SIZE=1]C 10.1.1.12 is directly connected, Serial0/0[/SIZE]
[SIZE=1]R 10.1.1.0 [120/1] via 10.1.1.10, 00:00:13, Serial0/1[/SIZE]
[SIZE=1] [120/1] via 10.1.1.6, 00:00:16, Serial0/2[/SIZE]
[SIZE=1]C 10.1.1.4 is directly connected, Serial0/2[/SIZE]
[COLOR=#ff0000][SIZE=1]R 192.168.1.0/24 [120/1] via 10.1.1.6, 00:00:16, Serial0/2[/SIZE]
[SIZE=1] [120/1] via 10.1.1.10, 00:00:14, Serial0/1[/SIZE][/COLOR]
[SIZE=1]SOUTH#sh ip route
[/SIZE][SIZE=1]Gateway of last resort is not set[/SIZE][SIZE=1]
[/SIZE]
[COLOR=#ff0000][SIZE=1]R 172.16.0.0/16 [120/1] via 10.1.1.1, 00:00:05, Serial0/2[/SIZE][/COLOR]
[SIZE=1] 10.0.0.0/30 is subnetted, 4 subnets[/SIZE]
[SIZE=1]R 10.1.1.8 [120/1] via 10.1.1.1, 00:00:05, Serial0/2[/SIZE]
[SIZE=1] [120/1] via 10.1.1.5, 00:00:03, Serial0/1[/SIZE]
[SIZE=1]R 10.1.1.12 [120/1] via 10.1.1.5, 00:00:03, Serial0/1[/SIZE]
[SIZE=1]C 10.1.1.0 is directly connected, Serial0/2[/SIZE]
[SIZE=1]C 10.1.1.4 is directly connected, Serial0/1[/SIZE]
[SIZE=1]C 192.168.1.0/24 is directly connected, FastEthernet0/0[/SIZE]
As you can see, it's a basic topology and auto-summary shouldn't have any effect on the routing tables, but something is happening with routes and specifically with hops to 192.168.1.0 & 172.16.0.0.
In Packet Tracer there are no effect on the routing tables with auto-summary ON (as expected), only in a real gear and GNS3 they change with auto-summary ON.
There is something that I'm missing?
Could be an IOS bug?
