HSRP EIGRP TWO DEFAULT ROUTES

[Fergal Meehan]

Hi,

I have a question concerning EIGRP routing on a L3 switch behind a HSRP HA pair of routers which connect to a WAN.

HSRP is operating as should be and when R1 fails, or an interface thereon, R2 becomes the active. All good.

However there are now two default routes in the route table on the L3 switch. One is routing traffic to the R2 real IP which is expected but also there is the old default route to R1's real IP.

Using EEM we can overcome this but is there another simpler method to prevent this occurring?

Thanks
F

[Jon Marshall]

F

If i understand correcty your LAN interfaces on the routers ie. the ones connecting to the L3 switch are running HSRP and you are also running EIGRP between the L3 switch and the routers.

If so you wouldn't usually have both solutions in use ie. you either -

1) use HSRP and point the default route on the L3 switch to the HSRP VIP

or

2) use EIGRP between the routers and the L3 switch. If a router or interface fails it should stop advertising the default route to the L3 switch.

However that sounds like it is not happening which suggests the default routes are not coming from the WAN.

So where are the default routes in EIGRP on the L3 switch coming from ?

Jon

[ALIAOF_]

How is he passing HSRP packets over the L3 interfaces though, I thought that was not possible?

[Jon Marshall]

Probably using a shared vlan between the router interfaces and the L3 switch.

So on the L3 switch end the connections would be L2 ports and then there would be an SVI for the vlan on the switch.

Jon
 

[ALIAOF_]

Ah I believe I did something like that but not for HSRP purpose but something like this:

Router:

Created a port channel with a /30 scheme

Switch:

Connected the router ports to the ethe-rchannel on the switch and created an SVI eg VLAN255 and put the ether-channels in VLAN255.

Setup a static route on the switch pointing to the VLAN255 interface on the router.

[shreerampardhy]

Hello F,

Please can you attach a small topology diagram?

Regards

Shreeram