1 / 55

DDS Objectives

DDS Objectives. DDS. Provide an overview of the key technical features of DDS Technology To introduce HPs DDS Technology product Family, and show where this technology is best deployed Compare HP products to our competitors Provide tools and references to further information.

parkerrobert
Download Presentation

DDS Objectives

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. DDS Objectives DDS • Provide an overview of the key technical features of DDS Technology • To introduce HPs DDS Technology product Family, and show where this technology is best deployed • Compare HP products to our competitors • Provide tools and references to further information

  2. Tape Technology Unit Shares: Dataquest DDS DDS maintains its position as the leading tape technology The DLT/LTO category is the fastest growing

  3. Why is DDS Technology so popular? DDS • Low cost of ownership – drive & media combination offer lowest cost tape technology • Good reliability – when used in the correct manner • DDS is a Standard, manufactured by HP, SONY & Seagate. 4 successful generations, each building on the previous generation installed base

  4. 150m tape Thinner tracks DDS History DDS DDS-4 DDS-3 DDS-2 (1999) DDS-DC (1995) (1993) DDS (1991) (1989) 90m tape Audio DAT 120m tape 125 m media Enabling Tehcnologies DCLZ Media spec MP+ media Increased bpi using PRML Groups Thinner C3 ECC tracks Format efficiency Native Capacity 2GB 1.3GB 4GB 12GB 20GB 183kB/s Transfer rate 183kB/s 360kB/s- 750kB/s- 1MB/s- 720kB/s 1.5MB/s 3MB/s

  5. HP DDS Product Family Native Capacity GB HP DAT40i/e/k/m DAT40x6i/e HP DAT24i/e/k/m DAT24x6i/e 20 12 HP DAT8i/e 4 Note:DDS1 now obsolete Native Performance GB/Hr 1.8 3.6 10.8

  6. Other Technical Specifications Each generation benefits from previous generation engineering enhancements

  7. 3 Current Generations of DDS DDS3 DDS2 Interchange Guaranteed Head cleaner, operates as necessary under firmware control. Mode Motor, drives all the mechanical loading/unloading and threading of tape. On DDS4 the W/R pre-amp is mounted on the rotating drum to get better Signal to Noise (SNR) performance. DDS4

  8. Cassette Switch Decoding • Holes in tape cassette inform the drive which type of tape is being used. Write Protect 1 2 3 D D 4 D=Datum hole Actual size Open=1 Closed=0

  9. DDS Tape - Basics DDS

  10. Read After Write DDS Read 2 Write 2 Write 1 Read 1 The data written on the tape is read after the write operation and checked for integrity.

  11. DDS Format Details DDS

  12. Mechanical loading process Moveable guides to “thread” the tape across the drum DDS Capstan motor “drives” tape across the head. Pinch roller acts as to engage the capstan motor onto the tape to get effective “drive”

  13. Track Layout DDS DDS 2 margin subdata ATF ATF subdata margin Main Data 128 Blocks DDS 3&4 margin margin Main Data 96 Fragments Main Changes: • No ATF zones • Subcodes embedded along tracks • C1 Blocks - Fragments

  14. Fragment ID (0 - 91) Header Area ID Frame Number Sub Code Information x 4 Data blocks from a G4 Sub Group Header Parity x2 (CRC) • Subcodes embedded along tracks • No ATF zones Track Details - DDS3&4 90° Margin P Main Data 96Fragments Margin Fragment Detail

  15. Why PRML? Used On DDS3 & DDS4 (Partial Response Maximum Likelihood) DDS • Enables 2x bit density without reducing read head gap • Head gap length 2x bit length • 3 level detection used • Recovers Signal to Noise Ratio (SNR) DDS2 Read Head Read Head DDS3&4 2 Decoded as part of a longer sequence 1 1 0 0 Peak detect PRML

  16. Some DDS 4 Engineering Enhancements

  17. ANY ANY Front panel display DDS Clean / Attention Tape Key Off Activity - Load/Unload Flashing Green period=1 Second Activity - Read/Write Flashing Green period=1/2 Second Tape Loaded - Unit Offline Green Media Caution Flashing Amber period=1 Second Fault Amber Self-test in progress

  18. DDS Autoloaders Entry Level Automation

  19. R R Z Z X X Y Y DDS autoloader – mechanism-basics X: cartridge horizontal movement R: magazine rotation Robotics PCB fits here Y: cartridge vertical movement Z: magazine horizontal movement Picker mechanism

  20. DDS-4 Autoloader – Sample Usage Model DDS 30GB Server This example illustrates how an automated backup could be set up for a 30GB capacity server to run for 3 months without manual intervention being required.

  21. Appropriate uses for DDS Technology DDS • Entry Level servers and workstations where the duty cycle does not exceed 3-4 hours per day • Ideal for cost effective large scale file transfers between machines. • Used on HP-UX systems to load the OS (using “ignite UX command”) • On “intel” systems DDS with HP OBDR is ideal for protecting the operating system and applications disks from system crash, even if the main data is backed up by higher capacity tape drives. • DDS Autoloaders ideal for remote office locations wanting to make backup as Automated as possible because of minimal IT staff.

  22. Ensuring a trouble free life with your HP DDS drive DDS • Use “native” tapes for best performance and reliability • Previous generation media is rougher and if used frequently can increase head wear. • Ensure drive streams • test system can supply data quickly enough with HP performance assessment tool (PAT – NT & W2K) • don’t “overload “ system during backups • Clean drive weekly with cleaning cassette • Don’t use autoloaders as big tape drives, this will exceed the designed duty cycles of the product • Use DDS4 – it is extremely reliable with an AFR < 3%

  23. DDS HP DDS COMPETITION For direct & indirect competition see http://brifpwww.bri.hp.com/competitionweb/default.asp Download the competitive folder (still current for DDS products)

  24. Summary of HP DAT advantages over competition DDS • #1 Market share in DDS technology (> 50%) • HP reputation for reliability • Widest Connectivity & Compatibility testing in the industry • Comprehensive TapeWare software in every box • OBDR – unique to HP DAT drives – quickest safest way to recover from a total system crash • Express Exchange – 24Hr replacement + system matching warranty on HP servers • HP DDS4 – fastest DAT drive available – here’s the proof!

  25. Hardware Setup DDS • Servers used HP LH4 and DELL 4300 • Dual Processor Intel 2, 400 MHz • 256Mb RAM • SCSI Hard disk for optimum transfer • Separate AHA2940 U2W to avoid bottlenecks • Microsoft NT version 4 with latest service packs • Latest versions of Backup Exec and ARCserve for Microsoft NT • Backups included SQL, Exchange as well as single large data file and the OS

  26. 20.00 25% CPU Loading 18.00 16.00 14.00 GBytes / hour 12.00 10.00 20.00 50% CPU Loading 17.20 16.10 8.00 18.00 14.20 12.24 6.00 16.00 8.92 4.00 14.00 GBytes / hour 2.00 12.00 0.00 10.00 QuantumDLT 4000 Sony DDS4(SDLT10000) ExabyteMammoth Sony AIT HP SureStoreDAT40 17.20 8.00 15.71 14.22 6.00 9.06 8.89 4.00 2.00 0.00 QuantumDLT 4000 Sony DDS4(SDLT10000) ExabyteMammoth Sony AIT HP SureStoreDAT40 Real-World Performance:Transfer Rates on a partially loaded server DDS The biggest factor affecting performance is the behaviour of the operating system and other processes running at the same time. But... Whatever the server loading, HP SureStore DAT40 is still the best performer.

  27. Average data file restore time under NT DDS

  28. Summary DDS • DDS technology will still be the predominant volume tape technology well into 2006 • DDS technology is still an ideal technology for entry level servers, workstations and unix servers because of its low total cost of ownership • DDS getting a new lease of life protecting OS & Application HDDs, utilising HP’s unique OBDR capability • When sold into the right environment DDS is a very reliable technology – especially HP DDS4

  29. Digital Linear Tape DLT, DLT-VS80 and SuperDLT

  30. DLT objectives DLT • understand the basic technology of digital linear tape • understand the differences between DLT, DLT VS80 and SuperDLT tape and their compatibility & interchangeability • be capable of specifying the correct technology for different customer requirements • provide references for further resources

  31. HP DLT Family - introduction DLT • DLT technology originally developed by DEC and then acquired by Quantum • DLT and SuperDLT tape are Quantum developed products sold by HP as SureStore DLT and SmartStorage products • SureStore originally aimed at the reseller marketplace for IA32 servers. SureStore will become the ‘universal product’ in Q4 ’01 • SmartStorage aimed at the enterprise HP-UX server with rack options • Quantum sold low cost DLT design to Benchmark Systems, now marketed as DLT VS (Value Smart) range

  32. 100GB current products data capacity GB(native) 40GB 6MB/s 50GB 35GB 5MB/s 40GB 3MB/s DLT8000 DLT-1 DLT VS80 DLT7000 DLT4000 DLT2000XT DLT600 DLT2000 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 DLT roadmap DLT

  33. HP DLT Family of products DLT Workstations, entry level Intel servers SureStore products SureStore products SMART Storage products DLT-1 and DLT-VS80 SureStore DLT80 DLT8000 SD class V ,N, L and A Mid Range & High End Intel servers Enterprise servers

  34. HP DLT rack solutions DLT module options TA5300 only SureStore Tape Array 5300 Ultrium 215m DVD ROM m September ‘01 DAT24m DAT40m SureStore Tape Array 5500 DLT VS80m DLT80m TA5300 & TA5500 Ultrium 230m rack solutions for PA-RISC, ia32 and ia64 servers

  35. HP current DLT portfolio positioning DLT Enterprise servers: LH6000 N-class Superdome Ultrium 215 230 DLT80 DLT-1 DLT-VS80 Mid-range servers: LH3000 L-class DAT40 DAT24 Entry level servers: E800 A-class DDS DLT Ultrium

  36. What is DLT? DLT • Linear tape recording • Data is written in linear tracks down the tape • The read-write head moves vertically to change tracks head rotation • Helical scan recording • Rotating read-write heads • tape wrapped around drum • drum is set at an angle to the tape 90° drum wrap

  37. very gentle head to media interface head designed to self clean adaptive calibration techniques very long media and head life under extreme stress multi-level error detection & correction long head & media life low maintenance excellent interchange lower cost of ownership secure data storage DLT technology features & benefits DLT

  38. what is DLT? - basics DLT • Diagram illustrates typical DLT tape path. Note the single spool cartridge.

  39. DLT– 4 channel linear recording DLT8000 formats DLT read-write head movement BOT EOT top edge of the tape head tilts read-write head has 52 positions = 208 tracks total. bottom edge of the tape

  40. Scratch Calibration Directory Data Area Area Area EOT BOT Leader Splice DLT tape layout DLT • scratch area - used to set write currents, determine the optimal tape tension. • calibration area - used to set the vertical position of the r/w head, density detection and align with data tracks for good interchange • directory area - used for fast search • BOT hole -physical beginning of tape (user data) • EOT hole -physical end of tape

  41. 1 Ft 2 BOTs Leader Cleaning tape 22.5 Ft BOT DLT tape III 43.5 Ft 2 BOTs DLT tape IIIxt 43.5 Ft BOT DLT tape IV DLT media recognition system DLT

  42. DLT load and unload DLT BOT/EOT sensor Head Tacho Take-up spool Leader Tape Link buckling mechanism Drive Hub Interposer/ Write Protect Sensor tape cartridge

  43. DLT load sequence DLT • Locate Edge of Tape • Find Calibration Tracks from Bottom of Tape • Find Calibration Tracks from Top of Tape • Develop Write Currents in Scratch Area • Read Directory • Erase Directory • Stop at BOT

  44. DLT performance tips - GENERIC DLT • SCSI transfers • should be at least 16kByte blocks • 32k blocks or bigger are preferred • use variable block mode (not fixed mode) • single large fixed blocks can work too • Host capabilities • CPU should be Pentium II • Disks should be at least fast SCSI-2 • Tape drive must have its own SCSI bus • If parallel streaming, DLTs should not share a common bus • Application (backup) software should use large buffers - 64KB in CA and Veritas

  45. Drive cleaning DLT • cleaning should only be performed when the cleaning light is ON use the correct cleaning tape • the cleaning light is turned on: • weak head signal during calibration • hard (uncorrectable) read or write errors • if the cleaning light is ON SCSI ‘request sense’ will return:cleaning request or cleaning required with status byte 18 = 81H • use only the approved cleaning cartridge

  46. DLT8000 read/write head DLT +/- 9deg DLT7000 and 8000 use symmetrical phase recording write head elements (8) read head elements (4)

  47. DLT8000 symmetrical phase recording DLT • Track Width 0.0445mm Tape Direction Track 3 Track 2 Track 1 Track 0 Bottom Edge of tape DLT8000 SPR1 recording format

  48. DLT8000 head tilt mechanism DLT

  49. DLT8000/mechanism DLT read write head assembly guide rollers DLT8000 cartridge receiver take up spool (modified from DLT7000) tachometer

More Related