LTO-8 and LTO-9 are both mature, widely supported generations of LTO tape. If you are buying drives or media today, which should you choose? Here are the key differences and five reasons most buyers choose LTO-9, plus the situations where LTO-8 still makes sense.
LTO-9 vs LTO-8 at a glance
| LTO-9 | LTO-8 | |
|---|---|---|
| Native capacity | 18 TB | 12 TB |
| Compressed capacity (2.5:1) | 45 TB | 30 TB |
| Native transfer rate | 400 MB/s | 360 MB/s |
| Compressed transfer rate | 1,000 MB/s | 900 MB/s |
| Drive reads/writes | LTO-9, LTO-8 | LTO-8, LTO-7 |
| Data tracks | 8,960 | 6,656 |
| New-cartridge optimisation | Yes (one-off) | No |
| Encryption / WORM / LTFS | Yes / Yes / Yes | Yes / Yes / Yes |
5 reasons to choose LTO-9
1. 50% more capacity
LTO-9 stores 18TB native against LTO-8’s 12TB, so the same library slot holds 50% more data. For growing data sets, that means fewer cartridges, fewer slots and lower handling costs.
2. Faster transfers
LTO-9 streams at 400MB/s native (1,000MB/s compressed) against 360MB/s (900MB/s) for LTO-8. That shortens backup windows and speeds up restores of large volumes.
3. It reads and writes your LTO-8 tapes
LTO-9 drives are fully read/write compatible with LTO-8 media. You can upgrade drives now and keep using your LTO-8 cartridges, with no forced migration. The catch is that LTO-9 drops support for LTO-7. LTO-8 drives support LTO-7, but LTO-9 supports only one previous generation. See LTO-9 compatibility.
4. Lower cost per terabyte over time
Higher density means fewer cartridges to buy, store, transport and track for the same data. For growing archives, LTO-9 usually works out cheaper per terabyte stored across the life of the system.
5. A longer support runway
LTO-9 is newer, so drives, media and vendor support will be available for longer than for LTO-8. That matters for archives you need to read for many years.
What about compression and encryption?
Both generations use the same 2.5:1 compression ratio and the same AES-256 hardware encryption. Both support WORM and LTFS. Security is the same for both, so the decision comes down to capacity, compatibility and cost.
When LTO-8 still makes sense
- You still need to read or write LTO-7 media regularly
- You are adding identical drives to an existing LTO-8-only library, and the cost of change outweighs the capacity gain
- You use LTO-7 Type M (9TB) media, which only LTO-8 drives support
Conclusion
For most organisations, LTO-9 is the better buy: more capacity, more speed, a longer life ahead, and full compatibility with existing LTO-8 tapes. Before you switch, check whether you still need to read LTO-7. If you are planning a completely new system, look at LTO-10 as well.
See LTO-9 tapes and LTO-8 tapes, or ask us which fits your environment.