Okay so you have been able to enter you network routes using the “route add -net” command but then you reboot the server and DAM you have to put the routes back in. Well here is the solution.
Go to you network configuration file and open it up with your text editor
Once your config file is open in nano or vim add the following to the bottom of the config file so when the network interface comes up your routes will automatically be added
up route add -net 10.0.0.0/8 gw 192.168.2.1 dev eth0 up route add -net 172.16.0.0/12 gw 192.168.1.1 dev eth1 up route add -net 192.168.0.0/16 gw 192.168.1.1 dev eth1