Multiple GRE's on one router

[ubuntu_guy]

I'm going to be setting up eigrp over gre over ipsec on my hub and spoke network. On my host router will I have to have a seperate tunnel interface for each remote site or can I configure just one tunnel interface and have it for all the tunnels?

Thanks.

[Giuseppe Larosa]

Hello Richard,

you are going to route over the GRE tunnel, so if it acceptable for you that to reach any other remote site the router goes via hub you need just one point to point GRE tunnel from each spoke to the hub router.

If you need to build tunnels to other remote sites for specific needs like VoIP and so on you should consider to use DMVPN Phase2 with dynamic spoke to spoke tunnels.

DMVPN uses point to multipoint GRE tunnels with NHRP pretending that all devices are in a single IP subnet.

see DMVPN design guide

http://www.cisco.com/en/US/docs/solutions/Enterprise/WAN_and_MAN/DMVPDG.html

Hope to help

Giuseppe