How to mount a disk in Proxmox VE and use it for VMs or storage

Start by identifying the new disk with commands such as lsblk or fdisk -l to confirm the device name. A new disk has to be partitioned first; fdisk or parted can create the partition table and the partitions. Then format the disk with a filesystem such as ext4 or xfs, or set it up as LVM or ZFS, depending on the storage design you want.

Once formatted, mount the disk to a directory, commonly under /mnt or another path you choose, with the mount command. To keep it mounted after a reboot, add an entry to the /etc/fstab file.

With the disk mounted at the operating system level, you can add it to Proxmox in the web interface. Go to Datacenter → Storage → Add, pick the storage type (Directory, LVM, ZFS, etc.) and enter the mount point or volume group. The storage is then available for VM disks, ISO images, backups or container volumes.

Plan before you change anything. Check the disk's health, choose the storage backend that fits your performance and redundancy needs, and make sure backups are in place before you make structural storage changes.