We have a backup internet connection that is tied into our Test Lab environment. As a part of this, I needed to change the default gateway on all of my Test Lab VMs so that everything would go out the proper connection. Now, I could RDP into each one and make the change, but that is boring and this is a LAB! It’s time to play a little bit and see if we can change this efficiently.
My initial thought was to use a combination of "psexec" and "netsh" commands to change that IP. I figured out the netsh command necessary to change an IP address (including the default gateway) and just left the IP address information out of the command. Much to my surprise, it set the adapter to DHCP, yet statically configured a default gateway. For our LAB this doesn't work since DHCP doesn't grab an address, but at least now I know. So how do you go about scripting a change to the default gateway for multiple Windows systems?
Use a route add command, of course! Using psexec to push the command out, I ran “route add -p 0.0.0.0 mask 0.0.0.0 10.1.1.1” where 10.1.1.1 is my new default gateway. Much to my surprise, it changed the default gateway entry on the adapter without issue.