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    IPSec Site-to-Site VPN behind ISP modem

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    • J
      jauintm
      last edited by jauintm

      Hi,

      I'm trying to establish IPSec Site-to-Site tunnel between Cisco 4321 router with a public IP and Netgate SG-2100 behind ISP modem with private IP on the WAN port. But no luck yet.

      Cisco router(Public IP) -- Internet -- ISP modem(DHCP public IP) -- SG-2100(Private IP, 192.168.x.x on the WAN)

      Do I need to do some port forwarding on ISP modem?
      or do I need to some specific configuration for Cisco router and SG02100?
      Please advise..

      DaddyGoD 1 Reply Last reply Reply Quote 0
      • DaddyGoD
        DaddyGo @jauintm
        last edited by

        @jauintm said in IPSec Site-to-Site VPN behind ISP modem:

        SG-2100(Private IP, 192.168.x.x on the WAN)

        Hi,

        Why are you using dual-NAT?
        can you put the modem(ISP) in bridge mode?

        otherwise it may be a solution:
        NAT Traversal - IPSec over NAT

        f.e.: http://www.internet-computer-security.com/VPN-Guide/NAT-T.html

        Cats bury it so they can't see it!
        (You know what I mean if you have a cat)

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