Hello guys,
I setup up a IPsec tunnel between checkpoint and a 3rd party VPN. Everything works fine without any problem.
The question is that when I connect one router (R1) to the gateway(R77.30) and put one PC(WS2012R2-4) behind the router the tunnel not worked as expected.
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Behind the router I have the network 10.1.1.0/24 and I do some NAT manipulation on the gateway, like that:
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I want to manipulate the traffic coming from the PC 10.1.1.10 to appear in the tunnel on the other side with the Source 172.16.3.20.
I setup my firewall rule to work with the VPN Community, like that:
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The VPN Domains in both sides are the Networks: 172.16.3.0/24(Checkpoint) and 172.16.1.0/24(Fortinet).
The problem is that host 10.1.1.10 cannot fire up the tunnel and all other hosts on the network 172.16.3.0/24 can setup the tunnel. I don't have the NAT disabled on the Community and the gateway and router have routes setting up for routing purposes, I don't think this is a routing issue.
I captured traffic with the wireshark from the outside interface eth0 (See the topology above), and I forced traffic through the tunnel with the PC 10.1.1.10, but nothing happened, please see below the packets:
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Source NAT works fine, but I cannot setup the tunnel, why this happen?
What am I doing wrong? What is left to do?
Thanks in advanced