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    NAT before IPSec

    Scheduled Pinned Locked Moved NAT
    23 Posts 6 Posters 7.1k Views
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    • T Offline
      tleiras
      last edited by

      Thanks a Lot.

      I'll try this configuration.

      Thanks.

      Thiago Leiras

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      • T Offline
        tleiras
        last edited by

        Hi Vononka,

        Did you have to set 1:1 or Outbound Nat configuration?

        When you send a package from Site A to Site B, what is the src ip when this package arrive at site B host?

        I'm sorry for my english.

        Thiago Leiras

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        • V Offline
          vononka
          last edited by

          Hi,
          No, but the subnet  192.168.1.0/24 is nated to 10.10.1.0/24 and 192.168.10.0/24 in 10.10.10/24.
          the virtual IP and the subnet must have the same netmask.

          Vononka

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          • T Offline
            tleiras
            last edited by

            Thanks a lot.
            I'll try this configuration today. After all I'll send news.

            Thanks.

            Thiago Leiras

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            • T Offline
              tleiras
              last edited by

              Hi,

              I've tried setup configuration as sugested, but this didn't work  :'(.

              My B side is a ipcop firewall and I tried establish vpn connection with site A using as remote address 172.16.24.0/24. On A site I configured Local Network wih 192.168.1.0/24 and Nat/BitNat with 172.16.24.0/24.

              On B site, the vpn status is Ok, but on PfSense (Site A) the VPN connection is down, although there are logs registering connection established.

              I'm attaching my actual configuration and log files on both sites. Does anyone has any idea why my Site A (192.168.1.0) package does not arrive at site B (10.1.1.0) with 172.168.24.0 address?

              Thanks a lot for help me.

              SiteAConfigThiago.png
              SiteAConfigThiago.png_thumb
              SiteBConfigThiago.png
              SiteBConfigThiago.png_thumb

              Thiago Leiras

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              • T Offline
                tleiras
                last edited by

                What about your configuration between Site A and Site C? Did you establish connection?
                In your original post you described that site A and Site C have the same CIDR. In this case did you have to Nat your Site A address to arive in site C with other network address?

                I'm sorry for the inconvenience.

                Thiago Leiras

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                • T Offline
                  tleiras
                  last edited by

                  Hello,

                  I succeed establish NAT before IPSec on Both sides.

                  I think the problem is with IPCOP. When I configure IPSEC VPN between 2 pfsenses (Site A 2.1 and site B 2.0.3), vpn works fine and all packages sent by site A arrives at Site B with 172.16.24.0 address. I'll check IPCOP documentation.

                  Thanks everyone for help me.

                  Thiago Leiras

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                  • T Offline
                    tleiras
                    last edited by

                    Hello,

                    I succeed establish NAT before IPSec on Both sides without problem.  :D

                    The problem was on my IPCOP on Site B. My firewall established connection on SonicWall using Nat Over Ipsec.

                    Thanks everyone for help me.

                    Thiago Leiras

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                    • S Offline
                      shadokin
                      last edited by

                      On your VIP you create, I assume you used a Localhost IP Alias?

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                      • dotdashD Offline
                        dotdash
                        last edited by

                        You shouldn't need to create VIPs or routes. You can set the NAT network directly in your phase2.

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                        • S Offline
                          shadokin
                          last edited by

                          Understood dotdash but Andry Vononka states he created a VIP and I was curious on that point. I am trying to do this with NAT to NAT on two externals and was curious if he used the VIP to point the traffic. I understand it 'SHOULD' work they way you stated and I agree but it's not. When I originate traffic from the internal network pointing to the IP of the local network on the other side of the tunnel, which is also a NAT'd external address it doesn't send the traffic down the tunnel. This is what it looks like….

                          Customer Server 10.200.1.122 (I do not use this as they NAT everything to 1.1.1.98)
                          Customer NAT 1.1.1.98 (assume internet routable IP)
                          Customer Gateway 1.1.2.241 (assume internet routable IP)
                          My Gateway 2.2.2.34 (assume internet routable IP)
                          My NAT 2.2.2.50 (assume internet routable IP)
                          My Server 192.168.20.67 (Customer does not see this address as I NAT everything to 2.2.2.50

                          The tunnel comes up just fine but can't seem to get traffic to route from 192.168.20.67 to 1.1.1.98 as I should be able to. Note when it arrives on 1.1.1.98 it should look like it's coming from 2.2.2.50 via the NAT from out side.

                          Any help is welcome in advance, thanks!

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                          • dotdashD Offline
                            dotdash
                            last edited by

                            Does the partner require you to nat to a public ip? I usually use this where there are overlapping subnets and use a different private. e.g. 192.168.1.0/24 real lan nat network 10.4.5.0/24 (the other side sees the 10.4.5 instead of 192.168.1)

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                            • T Offline
                              tleiras
                              last edited by

                              I used with network address only. Eg. 192.168.10.0/24 to 192.168.5.0/24.

                              Thiago Leiras

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