LTO vs SDLT
From Documentation
| Revision as of 12:11, 26 June 2006 Moff (Talk | contribs) ← Previous diff |
Revision as of 12:13, 26 June 2006 Moff (Talk | contribs) (→Notes) Next diff → |
||
| Line 111: | Line 111: | ||
| ==== Notes ==== | ==== Notes ==== | ||
| - | * SDLT600 is backward compatible with Super DLTtape II 300 GB - READ AND WRITE native capacity, Super DLTtape I 160 GB - READ ONLY native capacity & DLTtape VS1 80 GB - READ ONLY native capacity. | + | * SDLT600 is backward compatible with Super DLTtape II 300 GB - READ AND WRITE native capacity, Super DLTtape I 160 GB - READ ONLY native capacity and DLTtape VS1 80 GB - READ ONLY native capacity. |
| - | * SDLT 320 is backward-read and -write compatible with the SDLT 220, and backward-read compatible with the DLT 8000, DLT 7000, DLT 4000, DLT VS80 , and DLT1 using DLTtape IV media. | + | * SDLT 320 is backward-read and -write compatible with the SDLT 220, and backward-read compatible with the DLT 8000, DLT 7000, DLT 4000, DLT VS80, and DLT1 using DLTtape IV media. |
Revision as of 12:13, 26 June 2006
Technical Note
Two competing tape technologies dominate the enterprise backup segment, LTO and SDLT. The current top 2 drive technologies are LTO3 and SDLT600 respectively. Both products represent evolution from a previous generation rather than complete new products. This is preferable as it ensures compatibility with a large range of existing tape libraries and provides backward read compatibility with the previous generation of product. Both factors offer continued protection of investment.
The LT03 significantly raises the bar, both in capacity per tape and with significantly higher drive transfer rates. To obtain the maximum performance from these new drives it will be important to use a back-up server equipped with the appropriate newer generation of high speed interface cards (see SCSI Information). Typically these servers will utilise PCI-X interface technology which provides internal bus speeds capable of supporting these data rates. [Functional Software has conducted testing with these higher performance drives and can ensure you get the most from your implementation of LT03 based libraries.]
DLT tape has been the other tape standard for enterprise use for many years. There are thousands of companies around the world that rely on this well proven technology to protect their data. The SDLT600 is read compatible with the SDLT320 but utilises a new cartridge, Super DLTtape II, to obtain its 300Gbyte native (600Gbyte compressed) capacity. The previous generation product, the SDLT 320, used the same Super DLTtape I cartridges as the SDLT 220 and is backward read compatible with DLTtape IV media, preserving investments in previous DLT technologies. For this reason alone DLT will continue to be a player in the tape market.
In the comparison table below the HP Ultrium LTO2 product specs have been used. The HP drive incorporates Adaptive Tape Speed which dynamically matches the transfer rates of slower hosts (from 10 MB/s upwards), which increases performance, reduces mechanical wear on the drive and extends tape life.
Comparison Chart
| LTO3 HP Ultrium 960 | SDLT600 Quantum | LTO2 HP Ultrium 460 | SDLT320 Quantum | |
|---|---|---|---|---|
| Native Capacity (GB) | 400 | 300 | 200 | 160 |
| Compressed Capacity (GB) | 800 | 600 | 400 | 320 |
| Media Type | MP² | AMP¹ | MP² | AMP¹ |
| Drive | LT03 Ultrium | SDLT600 | LT02 Ultrium | SDLT320 |
| Drive Transfer Rate (Native) (MB/s) | 80 | 36 | 30 | 16 |
| Drive Transfer Rate (Native) (GB/h) | 288 | 133 | 108 | 57 |
| Drive Transfer Rate (Comp.) (MB/s) | 160 | 72 | 60 | 32 |
| Interfaces Available | LVD ULTRA, 320 SCSI, 2 GB Fibre Channel | LVD ULTRA, 160 SCSI, 2 GB Fibre Channel | LVD Ultra-3 SCSI, 2 GB Fibre Channel | Ultra 2 LVD and HVD SCSI |
| Cartridge Memory | LTO-CM | No | LTO-CM | No |
| Compression Technology | ALDC ( 2 : 1 ) | DLZ (2 : 1) | ALDC ( 2 : 1 ) | DLZ (2 : 1) |
| MTBF - hours | 250,000 | 250,000 | 250,000 | 250,000 |
| Form Factor | 5.25inches | 5.25inches | 5.25inches | 5.25inches |
| Backward Read Compatible? | Read and write compatible with LTO2. Read compatible with LT01 | Read and write compatibility with SDLT320. See notes below | Read and write compatible with LTO1 | 1st generation. Read compatibility with dual-head design. See notes below |
| Backward Write Compatible? | Read and write compatible with LTO2 | No | Read and write compatible with LTO1 | No |
¹ AMP : Advanced Metal Particle
² MP : Metal Particle
Notes
- SDLT600 is backward compatible with Super DLTtape II 300 GB - READ AND WRITE native capacity, Super DLTtape I 160 GB - READ ONLY native capacity and DLTtape VS1 80 GB - READ ONLY native capacity.
- SDLT 320 is backward-read and -write compatible with the SDLT 220, and backward-read compatible with the DLT 8000, DLT 7000, DLT 4000, DLT VS80, and DLT1 using DLTtape IV media.