LTO Tape FAQ

LTO-6 onwards assume 2.5:1 compression; LTO-1 to LTO-5 assume 2:1.

LTO drives compress data in hardware as they write it. Compressed capacity assumes a typical ratio (2.5:1 for LTO-6 onwards). Text, databases and logs often compress well. Video, images and data that is already compressed or encrypted barely compress at all, so plan on native capacity for those.

The LTO Program publishes a multi-generation roadmap. After the November 2025 update it runs to LTO-14 at 365TB native (913TB compressed), with a new generation every two to three years. See the LTO roadmap.

It depends on the generation. LTO-1 to LTO-7 drives read two generations back (for example, LTO-7 reads LTO-5). LTO-8 and LTO-9 drives read only one generation back. LTO-10 drives cannot read any earlier generation. See the full compatibility chart.

LTO-2 to LTO-9 drives can write to cartridges one generation back, in that older format. For example, an LTO-9 drive writes LTO-8, and an LTO-8 drive writes LTO-7. LTO-10 drives write only LTO-10.

No. A drive can never use a cartridge from a newer generation. You can put an LTO-6 tape in an LTO-7 drive, and it will work at LTO-6 capacity.

Yes, in most modern libraries. Partitioning lets you run, for example, an LTO-10 partition for new backups and an LTO-9 partition for restoring older LTO-8 media. Your backup software tracks each cartridge by its barcode label.

WORM (Write Once, Read Many) cartridges can be written and appended to, but existing data can never be overwritten or erased. That makes them tamper-proof, and ideal for evidence, compliance archives and ransomware protection. More on the LTO WORM page.

The Linear Tape File System stores a file index on the tape itself (LTO-5 onwards), so a cartridge can be mounted and used like a large USB drive, with drag and drop in Windows, macOS or Linux. You don’t need backup software to read it. More on the LTFS page.

Yes. Since LTO-4, drives include hardware AES-256 encryption (AES-GCM), which encrypts at full speed and also checks data integrity. You can encrypt in the drive, managed by the library or backup software, or in the backup software itself. Keep your encryption keys safe. Without them, the data cannot be recovered.

Standalone drives are available with SAS or Thunderbolt connections. Autoloaders and libraries add Fibre Channel, and some support iSCSI.

A device that reads and writes LTO cartridges. It comes as a 5.25″ half-height internal drive or as an external desktop unit, and is used to back up and restore servers and workstations. See LTO tape drives.

A 1U or 2U rackmount unit with one or two drives, typically 8 to 24 cartridge slots and a barcode reader. It rotates tapes automatically under the control of your backup software. See autoloaders.

A larger automated system with multiple drives and hundreds or thousands of slots, available as rackmount or floor-standing frames. See tape libraries.

Modern LTO drives are designed for demanding duty cycles. As an example, LTO-7 drives are rated at 250,000 hours MTBF at a 100% duty cycle. In practice, most organisations replace drives when they move to a new generation or when support ends.

All LTO Ultrium cartridges measure 102.0 × 105.4 × 21.5 mm (about 4.0 × 4.1 × 0.8 inches), so they fit the same library slots across generations.

Manufacturers rate LTO media for up to 30 years of archive life when stored in the right conditions. The practical limit is usually drive availability, not the tape. Plan to migrate to newer generations every few generations.

• Operating: 10–45°C, 10–80% RH
• Short-term storage: 16–35°C, 20–80% RH
• Long-term archive: 16–25°C, 20–50% RH
• Transport: −23 to 49°C, 5–80% RH

Avoid condensation. The maximum wet-bulb temperature is 26°C. Let cartridges acclimatise for 24 hours before use if they have been moved between environments. Exact figures vary slightly by manufacturer and generation.

Only when the drive asks. Modern drives request cleaning when they need it, and cleaning more than necessary wears the heads. In libraries, enable automatic cleaning and keep a cleaning cartridge in a reserved slot. See LTO cleaning tapes.

• Make at least two copies
• Keep the copies in separate locations
• Store tapes in a data-rated safe, not just a document fire safe
• Keep them within the recommended temperature and humidity range
• Every two to three years, recall a sample of tapes and check they read correctly

Enable verification in your backup software, so it reads back the data after writing, and carry out regular test restores. A backup you have never restored from is untested.

Linear Tape-Open is an open tape standard. It was created in the late 1990s by HP, IBM and Seagate as an alternative to proprietary formats such as DLT, and the first drives shipped in 2000. The LTO Program is now led by HPE, IBM and Quantum, and licensed manufacturers make compatible drives and media. See what LTO is and how it works.

For large volumes of data that must be kept but are rarely accessed, tape costs far less per terabyte, uses no power at rest, lasts decades and can be kept physically offline, out of reach of ransomware. It has also long been used in film and post-production to move footage between locations. Most organisations use tape alongside disk and cloud. See the benefits of LTO tape.

Yes: media from every major brand, barcode labels, cleaning and WORM cartridges, storage and transport cases, drives, autoloaders, libraries and backup software. Call 01256 331614 or contact us.