To the client, a package set appears to be a normal package. For information about using package sets on the server side, see Package Sets.
A package set has three possible states on the client: installed, not installed, or partially installed. "Partially installed" indicates that the package set has been installed, but that one or more of its component packages have been removed.
To avoid a partially installed state, you can lock the package set on the client with the rug lock-add command. This is equivalent to locking every package in the package set.
The client keeps track of the package set state.
You can use rollback with package sets just as you would with packages.