DMVPN with head end and remote sites configured with different subnets

[Nkechi Latunji]

Hi,

I have setup DMVPN as backup link to primary MPLS. I have mutual redistribution between ospf and bgp for the primary MPLS link. I am running EIGRP on the DMVPN and redistributing between ospf and EIGRP. My topology is two HQ sites and two remote sites. If I shutdown the MPLS circuits at the head end routers and the remote sites, the routing works fine over the DMVPN. In another instance when I only shutdown the MPLS circuit at a remote site, I can route over the DMVPN and reach networks at both HQ site but cannot reach the networks at the other remote site.

I noticed that when I shutdown the interface tunnel 0 or change the IP address on the router for the remote site I am unable to reach its networks, I can then reach these networks. 

Can I have a DMVPN setup where all the remote sites are on different subnets? If so what would the config look like or send me a link. I think this would sole my issue above

My setup for DMVPN is two head end routers and remote sites. 

Thanks

[Philip D'Ath]

You mention OSPF, EIGRP and BGP.

EIGRP is being used for DMVPN.  What is OSPF being used for? Is BGP being used to talk to the MPLS network?  What routing protocol(s) are the remete sites using?

Could you get rid of OSPF and just use EIGRP?  The more routing protocols you have the harder this is going to be.

[Nkechi Latunji]

BGP is used to talk to MPLS network and OSPF is used internal to the network. The remote sites are using eigrp, we are slowly converting them to ospf. I do not think i got an answer to my initial question if I can setup DMVPN with tunnel interfaces on different subnets

[Philip D'Ath]

You can run multiple DMVPN interfaces at the same time on the same router.  A common example is running dual DMVPN interfaces for a primary hub and a secondary hub.

All the routers in the same DMVPN "group" need to have their Tunnel interfaces in the same subnet.  If you add a second DMVPN connection then they will need to be in a different subnet.