I have two RAX45 routers.. one at home and one at my wife's office. I have the home router working fine. I am able to get to my home LAN using an OpenVPN client. This router is also set as the LAN DHCP server however.
My wife's office router is the problem. It is set to allow/block device access. So I have already given local devices access to the LAN, including a new laptop that will also be used away from the office as an OpenVPN client. This router does not handle DHCP since there is a Windows 2012 server handling IP addresses already.
I am able to connect to the router using its VPN cert/key. From within the LAN I can log into the router admin panel and see the laptop listed as a VPN conected device. The problem is that I am more or less jailed with an assigned IP that is not part of the LAN. I have been reading KBs, forums, How tos, etc. and trying many different things. I have found that the majority of these articles are responded to by others with "previous" or outdated knowledge. Many of the suggestions are deprecated. Some I have been able to work around. I have even started messing with setting up the Windows server to be a OpenVPN server and remote directly into the server. This is not preferred since the client laptop only needs acess to the LAN printers and NAS drives.
Its been at least a week and I need to get this done. Can anyone provide some suggestions or WORKING client config files? Or even a working server config file. I could go on and on about what settings I have tried, what the logs said, etc. I had my home VPN working in a couple hours. This office configuration cannot be this difficult. I am using the latest OpenVPN for Windows (2.5.5 perhaps).
When you connect to the VPN server, you will get a different IP range, but it will still allow you to communicate with other devices in other subnets. The only issue is some scans may not work if they do not allow you to specify a subnet, e.g., the basic network scan will not work in the network section of windows explorer, but local resources can still be accessed via their IP address.
For example suppose you have a system hosting an SMB share on IP 192.168.1.100, and you need to access that share over the VPN, It may not appear in the automatic network scan,but if you type in \\192.168.1.100 in the windows explorer address bar, the share will work.
One issue that can portntially happen is you have multiple routers on your network, is if the secondary router is using a LAN to WAN connection and effectively making a double NAT, then the VPN will not provide access into nay local resources beind that router u.nless you put it in AP mode, or disable its DHCP server, and changes its local IP to something else, and then dy a physical LAN to LAN connection between the 2 routers.
I tried pinging an ip on the remote office network and got a reply. So I realized that the VPN connection was letting me access the remote network even though no network adapters were reporting the proper IP range. Unfortunately the hostnames were not resolving. Pinging any host by name failed. Most of the software being run by this client laptop is already configured by the remote server to use hostnames, so I still had issues. I tried adding dhcp-option DNS <ip-to-remote-dns-server> and dhcp-option DOMAIN <mydomain.local> to the client laptop's VPN config file, but this did not get the hostnames on the remote network to resolve either.
In desperation I decided to join the laptop (running Windows 11 Pro) to the domain (Win Server 2012). After rebooting and reconnecting to the remote network, I am now able to ping any hostname on the remote network and get a reply. I am not sure why the dhcp-option settings did not help, but I was able to work around it.
