Is there a particular height at which I should mount a network cabinet?

There isn’t one universally correct height.

Mount it where the equipment can be reached safely, the door and side panels can be used properly, cables can enter sensibly and the cabinet won’t interfere with surrounding furniture, doors or other services.

Think about future maintenance as well as the initial installation. Mounting a cabinet almost against the ceiling may look wonderfully tidy until somebody needs to read a label on the top patch panel while standing on something that was never designed to be a ladder.

The right height is one that gives you sensible access throughout the life of the installation.