How do I format / reformat a single disk?

If a disk has never been seen by Swarm and it boots into a Swarm chassis, the disk will automatically format on bootup (or insertion in the case of hot plug).

If a disk has been retired from a cluster and needs to be reformatted, you need to access the System Menu on the Swarm storage node via remote terminal or Keyboard/ Monitor.

NOTE: To reformat even a single drive through this interface, the entire chassis will need to be taken offline during this process.

Choose 4. System Control; then choose 3. Stop storage processes.

Confirm that choice by choosing Yes.

At that point, you should see Storage Processes: STOPPED

Then choose 2. Disk Volumes

Arrow down to the disk in question and press "f"

The prompt will ask you to type: FORMAT to continue.  There is no formatting actually taking place at this point, so do not expect a delay.  The disk is being marked for re-format on next boot.

At that point, you can reboot the system under System Control.

The disk will be reformatted as the chassis mounts.