DiskId

DiskId is a term used to describe a unique identifier assigned to a storage disk to distinguish it from other disks in a system or network. DiskId can be hardware-based, such as a disk’s firmware or serial-number-derived identifiers, or software-based, such as GUIDs or UUIDs generated for volumes or partitions by the operating system or file system. In modern systems, the GPT partitioning scheme assigns a Disk GUID to the entire disk, while individual partitions have their own GUIDs. Many file systems also assign UUIDs to each volume to ensure stable references across reboots and hardware changes.

DiskId serves several practical roles. It allows software, scripts, and administrators to target a specific disk reliably for boot selection, imaging, backups, or recovery operations. Virtualization platforms and cloud environments use disk IDs to reference virtual disks consistently, even if device names or attachment order changes. In clustering, licensing, and inventory management, a persistent disk identifier helps tie activity or ownership to a particular physical or virtual device.

Limitations exist. Disk identifiers can change if the disk is replaced, reformatted, or cloned without preserving its identity. In virtual environments, IDs may be reassigned when disks are detached, moved, or reconfigured. Therefore, DiskId is most effective when it is tracked alongside other identifiers such as the disk’s serial number, WWN/NVMe namespace ID, or stable filesystem UUIDs.

See also: GUID, UUID, GPT, MBR, filesystem UUIDs, SCSI WWN, NVMe namespace.