View the storage config:

cat /etc/pve/storage.cfg

Verify the storage status:

pvesm status

Mount all storage:

mount -a

To add a disk:

• Datacenter > pve > Disks
• select the disk to be added, “Wipe Disk”
• Datacenter > pve > Shell
• run this command:

sgdisk -N 1 /dev/sdb

• back to Datacenter > pve > Disks
• The disk should be in GPT mode now