ip routing + static routes

[TrueFX]

Hello, I have 3 3750s in a traingle network. I am trying to set up redundant links between the three by using static routes. The only thing I have done to enable routing is "ip routing". I have not enabled a specific protocol such as RIP or OSPF.

The direct Point to Point routing works great. When I try to add a secondary route using metrics, nothing works when I take the primary link down. Is this even possible without enabling RIP / OSPF?

Thanks

[wiluszm]

TrueFX,

By using metrics do you mean creating of floating statics? In this example it should work for routing. We used to do this for corporate routing redundancy, and have now switched to iBGP with route-maps. Can you post your config and a copy of "sh ip route" when the link is connected and then removed? That should narrow down the routing issue.

-Mike

http://cs-mars.blogspot.com

[TrueFX]

Here is my "show ip route" :

Gateway of last resort is 192.168.1.4 to network 0.0.0.0

10.0.0.0/8 is variably subnetted, 8 subnets, 2 masks

C 10.152.20.0/24 is directly connected, Vlan20

C 10.152.30.0/24 is directly connected, Vlan30

C 10.152.10.0/24 is directly connected, Vlan10

S 10.151.0.0/16 [1/0] via 10.200.12.6

C 10.152.50.0/24 is directly connected, Vlan50

C 10.152.40.0/24 is directly connected, Vlan40

C 10.200.10.0/24 is directly connected, GigabitEthernet1/0/48

C 10.200.12.0/24 is directly connected, GigabitEthernet1/0/47

S* 0.0.0.0/0 [1/0] via 192.168.1.4

S 192.168.0.0/23 [1/0] via 10.200.10.1

As you can see, there are 3 "S"tatic routes. One route goes to the 10.151.0.0 network and one goes to the 192.168.0.0 network. I have no idea what the "S*" route is.

Following is my Config :

ip classless

ip route 0.0.0.0 0.0.0.0 192.168.1.4

ip route 10.151.0.0 255.255.0.0 10.200.12.6

ip route 10.151.0.0 255.255.0.0 10.200.10.1 10

ip route 192.168.0.0 255.255.254.0 10.200.10.1 permanent

ip route 192.168.0.0 255.255.254.0 10.200.12.6 10

What I have done to test my routes is to "shutdown" gig1/0/48 which should in turn make traffic go through gig1/0/47 (10.200.12.6). As you can see i added a metric of "10" to the config.

When I administratively shut down the port, traffic does not flow and it does not show the route in "show ip route". Any ideas on what I may be missing?

Thanks

[sundar.palaniappan]

Paul,

The config looks correct. Shutting down is not the same as the interface actually going down. To test this, unplug the cable from gig1/0/48 and you should see the floatic static route come into routing table and traffic should be forwarded out gig1/0/47.

BTW, "S*" indicates that it is a static route and gateway of last resort (default gateway).

Regards,

Sundar

[Richard Burts]

Paul

If I am understanding your situation correctly you are attempting to configure two floating static routes (routes for 10.151.0.0 and for 192.168.0.0). There is an issue with the floating static for 192.168.0.0. Your config has this:

ip route 192.168.0.0 255.255.254.0 10.200.10.1 permanent

which will put the route into the table. And the permanent parameter means to keep the route in the routing table no matter what. So the floating static for this will never work because the primary static will never be withdrawn.

The floating static for 10.151.0.0 should work if you test it right. The primary static uses the next hop on interface gig1/0/47 and the floating static uses interface gig1/0/48. So if you shut gig1/0/48 the primary still works and you have taken away the floating route. If you shut gig1/0/47 instead you should see the primary route withdraw and the floating static go into the routing table.

HTH

Rick