What is an LTO tape storage library?
A cabinet that holds many LTO cartridges in slots, one or more drives and a robot that moves cartridges between them, so backups and restores run without anyone changing tapes. Small ones are called autoloaders.
When you need one
Drive, autoloader or library
A single drive is enough while each backup fits on one cartridge and someone changes tapes. Once a job spans several cartridges, runs overnight, or you rotate tapes offsite every week, an automated changer pays for itself in staff time and missed backups.
- Autoloader: one drive and a magazine of about 8 to 16 slots in 1U or 2U. Good for a small office or a single server.
- Small library: one or more drives and 25 to 50 slots per module, expandable by stacking modules. Good for a mid-size estate or several backup streams.
- Enterprise library: hundreds to thousands of slots and dozens of drives, partitioned between applications.
Any of these is an LTO tape storage library: the cartridges stay in their slots, offline and powered down, until the robot loads one. How a library fits into a complete tape storage system is in LTO storage explained.
Models
Common autoloaders and small libraries
| Model | Type | Slots (base unit) | Notes |
|---|---|---|---|
| HPE StoreEver 1/8 G2 | Autoloader | 8 | 1U, one drive |
| Dell PowerVault TL1000 / IBM TS2900 | Autoloader | 9 | 1U, one half-height drive |
| Quantum SuperLoader 3 | Autoloader | 16 | 2U, two 8-slot magazines |
| Quantum Scalar i3 | Library | 25 | 3U modules, scales up |
| IBM TS4300 / Dell PowerVault ML3 | Library | 40 | 3U modules, scales up |
| HPE StoreEver MSL3040 | Library | 40 | 3U modules, scales up |
| Qualstar Q-Series, Spectra Stack | Library | Varies | Modular, LTO-9 and LTO-10 drives |
Slot counts are for the base unit with its standard configuration; check the data sheet for the drive generations each model supports. Library drives are sold as modules for that library.
What to check
Buying checklist
- Drive generation and count. Two drives let you copy tape to tape and run backup and restore at the same time.
- Interface. SAS for one host, Fibre Channel to share the library across a SAN.
- Barcode reader and labels. Libraries track cartridges by barcode, so every tape needs a label in the right format. See labels and cleaning tapes.
- Mail slots. I/O slots let you take cartridges offsite without opening the magazine.
- Software support. The library model, not just the drive, must be on your backup software's support list.
- Partitioning and encryption key management if several applications or teams share it.
Capacity
How much a library holds
Multiply slots by native capacity: a 40-slot library holds 720 TB on LTO-9 or 1.2 PB on 30 TB LTO-10 cartridges, before compression. Keep a few slots for cleaning cartridges and for tapes waiting to go offsite. Cartridge prices are in the LTO price tracker.
More guides
Other LTO guides
What is LTO tapeThe format in one pageLTO storageHow tape storage works and costsLTO capacity chartLTO-1 to LTO-14LTO tape drive buying guideWhich drive to buyLTO tape lifespanHow long tapes lastLTFS explainedTape as a file systemLTO tape data recoveryReading old tapesCleaning tapes and labelsSupplies and handlingLTO tape newsWhat changed this month
Pricebook
Get the LTO pricebook
Request current LTO media and drive pricing before you budget a migration or a refresh.
What is the difference between an autoloader and a tape library?
An autoloader has one drive and a single magazine of about 8 to 16 slots. A library has one or more drives, more slots, and can usually be expanded with extra modules.
How many tapes does a small LTO library hold?
Base modules typically hold 25 to 50 cartridges, which is 450 to 900 TB on LTO-9, and most can be expanded by stacking modules.
Do tape libraries need barcode labels?
Yes. The library identifies each cartridge by its barcode label, so every data and cleaning cartridge needs one in the format the library expects.
Can I mix LTO generations in one library?
Usually yes, with drives of each generation, as long as the library and your backup software support both. Each drive still only reads its supported generations.