Issue with access lan when remote network is the same subnet



  • Hello,

    I am using iOS with OpenVPN connect.  Over cellular I can browse the internet just fine and access local resources, but if I am on a public hotspot with the same subnet as my home network it will always resolve to the remote network resources.

    LAN: 10.0.0.0/255.255.0.0
    OpenVPN network: 10.140.0.0/16
    Example remote network 10.0.0.0/255.0.0.0

    I have force all traffic enabled and I push my local network in the advanced server settings.

    Is there any way to get OpenVPN to default to my LAN?

    Thanks!



  • Yes, that is an issue. If the network you are at (coffee shop, university…) happens to use a subnet that overlaps with your home subnet then there is trouble. If you are somewhere that has used 10.0.0.0/8 then that is a big pain! People should be setting up their networks with just small parts of that - 10.20.30.0/24 etc. Try to pick what you think is an obscure piece of private IP address space - 172.17.42.0/24 ... - for your home LAN and for the OpenVPN tunnel network.


  • Banned

    @phil.davis:

    People should be setting up their networks with just small parts of that - 10.20.30.0/24 etc.

    Hey, that's already taken by me, leave it alone!  ;D


  • Rebel Alliance Global Moderator

    ^ hehehehe, how can you be using it.. I am using it ;)



  • you can 1:1 NAT your home-lan to a "virtual" subnet over your vpn.

    for example:

    hotspot_your_ip = 10.0.0.200
    lan_host_you_wish_to_reach = 10.0.0.100    <<–- routing issue
    1:1 NAT your home_lan to 172.18.1.0/24  -------- from hotspot_your_ip you'd then connect to to 172.16.1.100 | and the NAT would have you end up on 10.0.0.100    <<--- routing issue "solved"

    i have a couple of sites where changing the lan-subnets is a ton of work (static ip's). I've used this method to circumvent possible routing issues