site-to-site vpn with virtual tunnel int - Cisco 851 router to MS ISA 2006

jasonww04 · ‎01-02-2009

I'm trying to set up a virtual tunnel interface for a VPN from a Cisco 851 router to Microsoft's ISA 2006. The VPN will go UP-ACTIVE and then go down. While it is up it appears no traffic passes through the tunnel. Prior to trying the vti the router had a crypto map for this connection. There is another VPN connection on the router to another site still using a crypto map and it works fine.

Ivan Martinon · ‎01-09-2009

I was not aware that Microsoft Servers support GRE over IPSEC tunnels, if you have confirmed that this is right, you would need to run some debugs on your router, debug crypto ipsec and debug crypto isakmp to find out the root cause of the tunnel bouncing.