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I'm running into something that is causing confusion when a VPN connection is down. Packets destined for the remote segment are sent back to the VPN's default gateway and then sent back to the VPN server. Creates a loop that confuses people when they do traceroute.</div>
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Default GW: 192.168.17.1</div>
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Routes: 192.168.19.0/24 -> 192.168.17.2</div>
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192.168.18.0/24 -> 192.168.17.2<br>
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VPN S: 192.168.17.2</div>
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Routes: 0.0.0.0 -> 192.168.17.2</div>
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192.168.19.1 -> 192.168.18.1<br>
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192.168.18.0/24 is used for the VPN endpoints</div>
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192.168.19.0/24 is used for DNAT rules on the VPN end point.</div>
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When the VPN is up, packets to 192.168.19.1 will go to 17.1 first, then 17.2, then 18.1, and finally 19.1</div>
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If 18.1 is offline then packets to 192.168.19.1 go to 17.1, then 17.2, and back to 17.1. This creates a loop.</div>
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Can I stop that? I thought about blocking 192.168.19.0/24 on eth0 with iptables, but would that not black the return path when the VPN is up and connections work?</div>
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