Accidental routing loop
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I'm on a network with one gateway and one windows pc on the lan. I wanted to test OpenVPN so I VPNed to the gateway, using default server.conf. This works fine.
Then I configured server.conf to push the LAN subnet to the client. After vpning in a second time I couldn't ping either the VPN subnet or LAN subnet. Routing loop.
(LAN) (VPN) (loopback) (LAN)
10.11.12.0 -> 10.8.0.6 -> 127.0.0.0 -> 10.11.12.0What I don't understand is how the loopback interface, 127.0.0.0/8 points to the LAN interface.
I know the loopback gets to the LAN interface somehow because the first time I connected and 10.8.0.6 pointed to 127.0.0.1 my gateway was receiving pings.
windows route print:
Active Routes: Network Destination Netmask Gateway Interface Metric 0.0.0.0 0.0.0.0 10.11.12.1 10.11.12.254 10 10.8.0.1 255.255.255.255 10.8.0.5 10.8.0.6 1 10.8.0.4 255.255.255.252 10.8.0.6 10.8.0.6 30 10.8.0.6 255.255.255.255 127.0.0.1 127.0.0.1 30 10.11.12.0 255.255.255.0 10.11.12.254 10.11.12.254 10 10.11.12.0 255.255.255.0 10.8.0.5 10.8.0.6 1 10.11.12.254 255.255.255.255 127.0.0.1 127.0.0.1 10 10.255.255.255 255.255.255.255 10.8.0.6 10.8.0.6 30 10.255.255.255 255.255.255.255 10.11.12.254 10.11.12.254 10 127.0.0.0 255.0.0.0 127.0.0.1 127.0.0.1 1 189.25.78.113 255.255.255.255 10.11.12.1 10.11.12.254 10 224.0.0.0 240.0.0.0 10.8.0.6 10.8.0.6 30 224.0.0.0 240.0.0.0 10.11.12.254 10.11.12.254 10 255.255.255.255 255.255.255.255 10.8.0.6 10.8.0.6 1 255.255.255.255 255.255.255.255 10.11.12.254 10.11.12.254 1 Default Gateway: 10.11.12.1To fix the routing loop I can just push a separate subnet.