LTO-9 is the ninth generation of Linear Tape-Open technology and the last generation to keep backward compatibility. It was released in 2021 by the LTO Program (HPE, IBM and Quantum) and remains one of the most widely installed generations. Here are the full specifications and what they mean in practice.
LTO-9 specifications at a glance
Capacity
At 18TB native, LTO-9 holds 50% more than LTO-8. The capacity comes from more data tracks (8,960, up from 6,656) and a longer, thinner tape (1,035m of 5.2µm tape), using Barium Ferrite particles. With compression, a single cartridge can hold up to 45TB, depending on how compressible your data is.
Performance
LTO-9 drives stream at 400MB/s native and up to 1,000MB/s with compressible data. At full speed, one drive moves roughly 1.44TB per hour before compression. To keep the drive streaming, the data source needs to keep up. Staging backups on disk first usually gives the best results.
Media optimisation
Because of the very high track density, LTO-9 drives calibrate each new cartridge the first time it is loaded and store the results in the cartridge memory. This one-off optimisation takes on average about 40 minutes, and occasionally up to two hours. After that, the cartridge loads normally in any LTO-9 drive. Plan for this when you introduce new media: many libraries can pre-optimise cartridges in the background. (LTO-10’s new head design removes this step.)
Backward compatibility
LTO-9 drives read and write LTO-8 cartridges. Unlike earlier generations, they cannot read tapes two generations back, so LTO-7 media is not supported. See the LTO-9 compatibility guide for the full matrix.
Security
LTO-9 includes AES-256 hardware encryption at full speed, with keys managed by the drive, the library or your backup software. WORM cartridges provide immutability for compliance, and cartridges stored offline give you a physical air gap against ransomware.
LTFS
LTO-9 supports partitioning and the Linear Tape File System, so tapes can be mounted and browsed like a disk. That is ideal for exchanging large files and for self-describing archives.
Archive life
Stored within the manufacturers’ recommended conditions (16–25°C, 20–50% relative humidity), LTO-9 media is rated for up to 30 years of archive life.
Ready to buy? See LTO-9 tapes, or compare with LTO-10 specifications.