Disk data format

{{Short description|Standard format for data in RAID}}

The SNIA common RAID disk data format (DDF) defines a standard data structure describing how data is formatted across disks in a RAID group. The DDF structure allows a basic level of interoperability between different suppliers of RAID technology. The common RAID DDF structure benefits storage users by enabling in-place data migration or recovery after controller failure using systems from different vendors.{{cite web |url=http://www.snia.org/tech_activities/standards/curr_standards/ddf |publisher=Storage Networking Industry Association |title=Common RAID Disk Data Format (DDF) |website=SNIA.org }}

DDF is an external metadata format that is compatible with the mdraid subsystem in the Linux kernel. The mdadm command-line utility is a part of the mdraid subsystem.{{Cite web |title=Chapter 21. Managing RAID Red Hat Enterprise Linux 8 |url=https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/8/html/managing_storage_devices/managing-raid_managing-storage-devices |access-date=2023-01-06 |website=Red Hat Customer Portal |language=en}}