Problem accessing LAN from OpenVPN



  • I have a problem accessing LAN from OpenVPN from some networks, and I think I narrowed this down to an issue with overlapping subnets. My home LAN is on 192.168.1.x. Currently I am at a location that uses the same subnet, and I have no control over this. I can use OpenVPN to connect to the pfsense firewall at home, and I can access the internet (surf the web). However, I cannot connect to machines on the 192.168.1.x subnet. For example, when I try to connect to 192.168.1.1, I connect to the local router rather than my pfsense at home. I understand that the general advice is not to have overlapping networks, but when on travel, I have no control over what IP addresses hotels use. Is there a workaround with instructions that is easy to understand for a layman like me?



  • Is a roadwarrior setup?



  • To avoid conflicts as much as possible i made a list of subnets that manufacturers like to use as default.
    Best would be to NOT configure any subnets of following list on networks you control when OpenVPN is involved:

    10.0.0
    10.0.1
    10.1.1
    10.1.10
    10.2.0
    10.8.0
    10.10.1
    10.90.90
    10.100.1
    10.255.255
    
    169.254 # APIPA #
    
    172.16.0
    172.16.16
    172.16.42
    172.16.68
    
    172.19.3
    
    172.20.10 # IPhone hotspot #
    
    192.168.0
    192.168.1
    192.168.2
    192.168.3
    192.168.4
    192.168.5
    192.168.6
    192.168.7
    192.168.8
    192.168.9
    192.168.10
    192.168.11
    192.168.13
    192.168.15
    192.168.16
    192.168.18
    192.168.20
    192.168.29
    192.168.30
    192.168.33
    192.168.39
    192.168.40
    192.168.42 # Android USB tethering #
    192.168.43 # Android hotspot #
    192.168.50
    192.168.55
    192.168.61
    192.168.62
    192.168.65
    192.168.77
    192.168.80
    192.168.85
    192.168.88
    192.168.98
    192.168.99
    192.168.100
    192.168.101
    192.168.102
    192.168.111
    192.168.123
    192.168.126
    192.168.129
    192.168.137 # Windows Phone hotspot #
    192.168.168
    192.168.178
    192.168.190
    192.168.199
    192.168.200
    192.168.220
    192.168.223
    192.168.229
    192.168.240
    192.168.245
    192.168.251
    192.168.252
    192.168.254
    
    200.200.200
    


  • @periko: I do not know what roadwarrior is so I assume the answer is no.

    @pippin: I agree that would be a solution and it is the one I am trying to avoid.

    In the meantime, I found that on my android phone using the OpenVPN app, I can access the firewall with 192.168.1.1. Only on the MacBook Pro running Tunnelblick the before address lands me on the local router. Both systems use the same OpenVPN config files. It then seems this may be a Tunnelblick issue.



  • Or it could be Mac issue. I just tried Viscosity and it has the same issue.