Adding route on client using OpenVPN

Solution 1:

Looking at your routing table. There is no explicit route telling traffic to 172...* as you call it. To be sent to the VPN tun interface.

You have several options:

If you have access to the openVPN server add this directive to the openvpn config:
```
push "redirect-gateway def1 bypass-dhcp"
```
This setting will route/force all traffic to pass through the VPN. The other alternative you have. Is to add a static route yourself on the client side
Add the route manually on the client side in a terminal
```
sudo route add -net 172.16.0.0/24 dev tun0
```
openvpn has a directive for adding and removing of routes client side in your openvpn config file with with the route option.

Adding:
```
route 172.16.0.0 255.255.255.0
```
to your openvpn config file on the vpn client. will add the route automatically when you connect
Bonus: openvpn also has a up/down directive that allows you to launch a script on connect to VPN. This can allows you to do any custom action like setting DNS, routes etc. But it requires you to store the commands to execute in another file.

So if you had the following to your openvpn client config file
```
script-security 2 system
up run-stuff-after-vpn-connect.sh
```
Create a file named run-stuff-after-vpn-connect.sh (make sure it has execute permissions. And add:
```
#!/bin/sh
route add -net 172.16.0.0/24 dev tun0
```
This will add the route as soon as the tunnel is up

Since you didn't give us the full declaration of your subnet in your question assuming its 172.16.0.0/24