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duplicate ip address on wan interfaces when testing HSRP.

Hello expert,

I have two  3900 series routers configured as hubs (dmvpn ) to do HSRP.

I also configure three 2900 as spokes (dmvpn)

I configure route A as primary router and router B  backup.

Let me outline the configuration of Router A.

I configure the two onboard gigabit ports for IP dsl and wireless connections

A switch card was insert on router a given a address for lan connections.

I use dmvpn for the ip dsl tunnel and for the wireless I use site to site vpn with gre

To connect my Spokes to the primary hub ( router A)

On router B I am using the exact configuration use on router A

For the two routers

Router A

Ip dsl interface      ppp.ppp.ppp.100

Wireless interface      ddd.ddd.ddd.117

Lan interface

Virtual interface (for HSRP)

Router B

Ip dsl interface              ppp.ppp.ppp.100

Wireless Interface         ddd.ddd.ddd.117

Lan interface       

Virture interface

When I fire both router and do fail over testing simulating a primary router failure the

Backup is taken over seamless and continuing routing.



I am using hyperterm to do any minor adjustment but very often a message would break

on either router saying that there is duplicated address on the ip dsl and wireless


I know that this true because am using the same configuration on both routers the only unique addresse is on  the lan interfaces.

Can I use the exact configuration on rouer A and router B?

If  I have to modify the address of the backup router to have unique addresses how would

this affect my dmvpn  and site to site vpn configuration.?


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