two default route to internet on same spoke router

[jomo frank]

Hello Expert,                  

I have a hub and spoke network,which  has line redundancy configured for all spoke connection.

I am using eigrp as the routing protocol for all routing expected for the internet route, which use

a default route configured on each spoke.

To achieve line redunancy there are  two connections, wireless (primary connection)  and ip dsl (secondary connect) from hub

to each spoke.

I am using two default route so that in event of  line failure (wireless or id dsl ) the path to the internet should be reachable.

I notice  with this approach/method I am having problems when the primary connection drops the failover

to secondary(ip dsl line) is seemless for the eigrp generated routes, but the default route does not

change.

I was hoping that when the first default route becomes unavailable the second would be use but this

Not happening.

Regards

Jomo

[Rahul Kukreja]

Jumo,

I took a look at the attached configuration, you are using the permanent keyword with the static route

ip route 0.0.0.0 0.0.0.0 Tunnel0 permanent

ip route 0.0.0.0 0.0.0.0 Tunnel1 permanent

Permanent keyword specifies that the route will not be removed, even  if the interface shuts down.

http://www.cisco.com/en/US/docs/ios/iproute_pi/command/reference/iri_pi1.html#wp1037816

EIGRP neighbors (so in turn the routes learned from that neighbor) should go down if the hello packets are not received, but static routes may not.

Also in the above desciption - it is specified that the routes are primary/backup and in the configuration - the AD value for both the routes is same.

- HTH

Rahul

[jomo frank]

hello Rahul,

If i change the metric at the end of the route and remove permanent as per example should this be be okay?

ip route 0.0.0.0 0.0.0.0 Tunnel0 2

ip route 0.0.0.0 0.0.0.0 Tunnel1 3

Regards

[Abzal · Accepted solution]

Hi Jomo,

I think what you are looking for is floating static  routes.Because your example with different AD will work if interface  will be down. But when you loose connection and if interface stays up.  It won't help.

There is great resource that will help you.

http://www.firewall.cx/cisco-technical-knowledgebase/cisco-routers/813-cisco-router-ipsla-basic.html

Hope it will help.

Please rate helpful posts.

[Ed Willson]

I concur - I posted the same link last week

[Rick Morris]

If you want the static routes to be used, one as the primary and one as the backup then all you need is the following:

ip route 0.0.0.0 0.0.0.0 Tunnel0

ip route 0.0.0.0 0.0.0.0 Tunnel1 100

This places the AD on the backup and will be used in the event Tunnel0 goes down.

[Ed Willson]

Rick - If you have two statics in there the best one will remain in the routing table. I'm pretty sure that's not going to work as the static is still there even if the link is down.

[Rick Morris]

Ed Willson wrote:
Rick - If you have two statics in there the best one will remain in the routing table. I'm pretty sure that's not going to work as the static is still there even if the link is down. 

Ed,

When using the interface at the end of a static route the route will be injected into the routing table as long as the interface is up.  In this config:

ip route 0.0.0.0 0.0.0.0 Tunnel0

ip route 0.0.0.0 0.0.0.0 Tunnel1 100

This is telling the routing table to inject the route based on what interface is up.  If both tunnels are up then tunnel 1 will not be the primary because of the AD.  If tunnel 0 goes down then the route is withdrawn.  This leaves Tunnel 1 as the preferred route in the table.

[Ed Willson · Accepted solution]

Hey Jomo,

     I'm thinking perhaps IP SLA might fit the bill. I used the following link for a branch that is multi-homed to reach the HQ for internet access:

http://www.firewall.cx/cisco-technical-knowledgebase/cisco-routers/813-cisco-router-ipsla-basic.html

Thanks,

    Ed