How to access a vpn network behind a router?

Question

openvpn

Good afternoon.
I want to organize a vpn tunnel between two offices. using openvpn. Both offices have routers. In office A there is a server on it the openvpn server network 10.8.0.1 is spinning. I would like to get access to the vpn network in office B. By installing the openvpn client, I have access. The question is, is it possible to connect to a server on a router or another server in office B so that all computers on their own network have access to the vpn network at 10.8.0.1 without installing openvpnclient on each computer?
1. If you put a router in office B with firmware that has an openvpn client, will the computers in its network have access to the vpn server from office A?
2. If the router does not support the openvpn connection function, how can all computers access the VPN server
Thank you

Answer 1

If the router in office B does not support the OpenVPN client, you can install the client on any computer and add routes on the router and on that computer. Then there will be access to A network.
If more. Suppose the network in office A is 192.168.1.0 , the VPN network is 10.8.0.0 (the VPN server address is 10.8.0.1 ), the network in office B is 172.16.1.0
In network B the default gateway is 172.16.1.1 , the VPN client is installed on computer 172.16.1.2 and has an address in VPN 10.8.0.2
You need to register 2 routes on the gateway in network B (1. Destination network 10.8.0.0 mask - 255.255.255.0, gateway 172.16.1.2 and 2. Destination network 192.168.1.0 mask - 255.255.255.0 gateway 172.16.1.2). On the computer with the VPN client, add the route Destination network 192.168.1.0 mask - 255.255.255.0 gateway 10.8.0.1. After that, access from any computer in network B to network A will appear. To access network A from network B, you need to add the route Destination network 172.16.1.0 mask - 255.255.255.0 gateway 10.8 on router A (if it is the default gateway). 0.2. If you add these routes on the specified devices, then you will have access to all computers in both networks.

Answer 2

If you connect from a router in office B to a server in office A, you need to add a route through the tunnel to the 10.8.0.0 network on the router.
If the router does not support then change the router or install a server