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New Member

VPN and Loopback interface

I am setting site-to-site VPN b/t Pix and cisco router. I currently don't have a network behind the Cisco router so I cam creating a loopback interface on the router for testing. When testing, I can see tunnel build but I can not get to the lopback interface on the router from a network behind the PIX.

Question: Is it possible to use the loop back interface as interesting traffic inside the tunnel or does it have to be on a network outside the router? Thanks.

  • Other Security Subjects

Re: VPN and Loopback interface

mm ... goos question .. I am 99% sure it shoudl be OK. what is your output from show crypto isakmp sa and show crypto ipsec sa ..?


Re: VPN and Loopback interface

Yes its possible iam using this scenarion in my lab without problems - it looks like some problem with configuration


New Member

Re: VPN and Loopback interface

Thank you for all the responses. After your confirmation that using Loopback was Ok, I found the problem in my config. I did not have a route from the router back to the remote network behind the PIX.


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