How to make a 12V distribution block for hard drives
Most power supplies have a continuous power allowed and a surge power for a short duration.  Select a power supply to have large enough values for both start up surge and normal full load of all drives.

To prevent shorts causing an issue, a PTC is probably the easiest.  These are devices that heat up as current flows through them.  They allow a certain level, but become high resistance (thus limiting current flow) when hitting 50% more than that level.  They will then reset when they cool down.  The surge current is fast enough that it will not trip the PTC, but a short would.  The PTC will pull as much as is needed to keep it in the shutoff region, but would not bring all drives down.