Ubuntu – How to get gateway of network interface

In VMware Workstation goto Edit > Virtual Network Editor then click on VMnet8 which should be your NAT adapter.

Then click on NAT settings, this will bring up a menu that will tell you what your NAT adapter gateway is (you will need that).

Once you have that you will need to then add a static route for your VPN subnet like so:

route add -net 10.1.50.0 netmask 255.0.0.0 gw 192.168.222.2

The syntax is:

route add -net $WORK-NETWORK netmask $NETMASK gw $NAT-ADAPTER-GW

Both networks should now be reachable from the VM.

If you want to add the route so it persists upon reboot you will then need to edit /etc/network/interfaces and add

# static route
post-up route add -net 10.1.50.0 netmask 255.0.0.0 gw 192.168.222.2 dev eth1

You can modify the gateway for network manager connections from the command line. So while I cannot find this option in the GUI, you can list the connections

nmcli con show

find yours

NAME                     UUID                                  TYPE             DEVICE 
thenameyougaveit         some-id-ksadbf019-aksb821           vpn              wlan1  

change the address (it will be discarded afaict but you cannot change the gateway address without setting it)

nmcli con mod some-id-ksadbf019-aksb821 ipv4.addresses 192.168.1.113/24

and then set the desired ip4 gateway

nmcli con mod some-id-ksadbf019-aksb821 ipv4.gateway 192.168.1.1

And now it works from the GUI. Of course, if anything changes on the other end, it will stop working.