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    Route old IP (from old, now non-existent subnet) to LAN IP

    NAT
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    • N
      Nesster
      last edited by

      I'm trying to find a solution to "catch" traffic for a non-existent IP (on a subnet that doesn't exist anymore), to no avail.

      Here's our network:
      WAN
      LAN -> 192.168.128.0/24

      Now, the router has no knowledge of subnet 192.168.10.0, but I want to "map" or "redirect" traffic addressed to 192.168.10.6 to say 192.168.128.13.

      I tried different things, VIP, 1:1 NAT, and searched a lot on this, can't figure it out. I'm thinking this should not be too complicated, I must be missing something …

      Reason for this is we had to change subnet, and we have a piece of software that had an IP hardcoded in it (and we don't have source code).

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      • dotdashD
        dotdash
        last edited by

        If it is traffic destined for the firewall, you should be able to add an alias IP and rules to allow it. Which interface does the traffic come in on, and where is the destination machine?

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        • N
          Nesster
          last edited by

          The network is really basic, all clients are on 192.168.128.0 subnet. Right now nobody knows about the 192.168.10.0 subnet. I guess I'll have to have a route for the 192.168.10.0 subnet and have my router IP 192.168.128.3 the default gateway for it.

          Traffic comes in the LAN interface (192.168.128.3), destination machine is 192.168.128.13

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          • dotdashD
            dotdash
            last edited by

            Tricky. Traffic shouldn't really be traversing the firewall at all if I'm following you. (Both source and destination are on the LAN)
            Crazy idea- maybe put a VIP on the WAN for 192.168.10.6, forward all needed ports to 192.168.128.13, enable NAT reflection- proxy+NAT for all NAT rules.

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