There are a couple of questions out there about how to add runas to a custom action, but I did not see any answers.
So here is how I got run as to work with computer management. There are several variations you can do with this but our need was to run computer manager as the local administrator (this enables us to add the domain admins into the local administrators group).
1. A local admin username and password must be the same on your local computer(where you are executing the runas command) and the computer you are connecting too.
2. Create a custom action with the following command -
runas /user:localadmin "mmc.exe compmgmt.msc /computer:{computer}"
That's it. When you run the custom action, you will be prompted for the password and then a few seconds later computer manager will load for the remote machine.
Once we get the domain admins group added to the local administrators group on all the machines we will change the /user:localadmin to /user:domain\domainadmin.
You should be able to configure most of your custom actions to runas an admin.
