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Transcript of HPSU training HP Restricted October 17, 2001 Page 2 DDS Objectives Provide an overview of the key...
October 17, 2001 Page 2
HPSUtraining
HP Restricted
DDS Objectives
• 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
DDS
October 17, 2001 Page 3
HPSUtraining
HP Restricted
Tape Technology Unit Shares: Dataquest
DDS maintains its position as the leading tape technology
The DLT/LTO category is the fastest growing
Tape Format Unit Share 2000
31%
6%
46%
4%
12% 1%
DC2000/Travan/ADR
DC6000/SLR
DDS
8mm (AIT/Mammoth)
DLT/LTO
Half-Inch
Tape Format Unit Share 2004
24%
4%
43%
5%
22%2%
DC2000/Travan/ADR
DC6000/SLR
DDS
8mm (AIT/Mammoth)
DLT/LTO
Half-Inch
DDS
October 17, 2001 Page 4
HPSUtraining
HP Restricted
Why is DDS Technology so popular?
• 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
DDS
October 17, 2001 Page 5
HPSUtraining
HP Restricted
DDS History
DDS DDS-DC
DDS-2DDS-3
DDS-4
(1989)(1991)
(1993)(1995)
(1999)
EnablingTehcnologies
Audio DAT 90m tape 120m tape 125 m mediaMedia spec DCLZ MP+ media Increased bpi
using PRMLGroups Thinner Forma
tC3 ECC tracks
efficiency
150m tapeThinnertracks
NativeCapacity 1.3GB 2GB 4GB 12GB 20GB
Transfer rate 183kB/s 183kB/s 360kB/s- 750kB/s- 1MB/s- 720kB/s 1.5MB/s 3MB/s
DDS
October 17, 2001 Page 6
HPSUtraining
HP Restricted
HP DDS Product FamilyNative
Capacity GB
Native Performance
GB/Hr
1.8 3.6 10.8
20
12
4
HP DAT8i/e
HP DAT24i/e/k/m
DAT24x6i/e
HP DAT40i/e/k/m
DAT40x6i/e
Note:DDS1 now obsolete
October 17, 2001 Page 7
HPSUtraining
HP Restricted
Other Technical Specifications
DDS2 DDS3 DDS4Primary Media usage for best performance
120m 125m 150m
SCSI Interface & connector
Single Ended Narrow SCSI 2 - 50 way
Single Ended Narrow SCSI 2 - 50 way
LVDS/SE
68 pin High Density
Backwards compatibility
Write/Read DDS1 (90m and 60m tapes)
Write/Read DDS2
Write/Read DDS1 (90m and 60m tapes)
Write/Read DDS3
Write/Read DDS2
Read-Only DDS1(90m)
Engineering Features Firmware controlled equalization adjustment (no pots)
Firmware upgrade over SCSI or Via Upgrade tape.
Increased Format efficiency.
Write read channel now PRML
Super Head-Clean mode
Active Drum
Capstan cleaner
Real time adaptive filtering
Advanced sequence detection
Each generation benefits from previous generation engineering enhancements
October 17, 2001 Page 8
HPSUtraining
HP Restricted
3 Current Generations of DDS
DDS2 DDS3
DDS4
Mode Motor, drives all the mechanical loading/unloading and threading of
tape.
Head cleaner, operates as
necessary under firmware control.
On DDS4 the W/R pre-amp is mounted on the rotating drum to get better Signal to
Noise (SNR) performance.
Interchange Guaranteed
October 17, 2001 Page 9
HPSUtraining
HP Restricted
Cassette Switch Decoding Holes in tape cassette inform the drive which type of
tape is being used.
1 2 3 4Write Protect
Open=1Closed=0
D D
D=Datum hole
TAPE TYPE HOLE 1 HOLE 2 HOLE3 HOLE 460m DDS-1 0 0 0 090m DDS-1 0 1 0 0120m DDS-2 1 0 0 0125m DDS-3 1 0 1 0150m DDS-4 1 1 0 0Cleaning Tape 0 0 1 0
Actual size
October 17, 2001 Page 10
HPSUtraining
HP Restricted
DDS Tape - Basics
DDS
October 17, 2001 Page 11
HPSUtraining
HP Restricted
Read After Write
Write 1
Write 2
Read 1
Read 2
The data written on the tapeis read after the write operation
and checked for integrity.
DDS
October 17, 2001 Page 12
HPSUtraining
HP Restricted
DDS Format Details
DDS
October 17, 2001 Page 13
HPSUtraining
HP Restricted
Moveable guides to “thread” the tape across the drum
Capstan motor “drives” tape across
the head.
Pinch roller acts as to engage the
capstan motor onto the tape to get
effective “drive”
Mechanical loading process
DDS
October 17, 2001 Page 14
HPSUtraining
HP Restricted
DDS 2
DDS 3&4
Main Data128 Blocks
Main Data96 Fragments
Main Changes: No ATF zones Subcodes embedded along tracks C1 Blocks - Fragments
marginsubdata ATF marginsubdataATF
marginmargin
Track Layout
DDS
October 17, 2001 Page 15
HPSUtraining
HP Restricted
Track Details - DDS3&4
90°
Margin P Main Data 96Fragments Margin
Fragment Detail
Header
Datablocksfrom aG4SubGroup
Fragment ID (0 - 91)Area ID Frame Number
Sub Code Information x 4
Header Parity x2 (CRC)
–Subcodes embedded along tracks–No ATF zones
October 17, 2001 Page 16
HPSUtraining
HP Restricted
Why PRML? Used On DDS3 & DDS4 (Partial Response Maximum Likelihood)
• 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)
Read
Head
Read
Head
0
1 2
1
0Peak detect PRML
Decoded as part of a
longer sequence
DDS2 DDS3&4
DDS
Page 17
October 17, 2001
HPSUtraining
HP Restricted
Some DDS 4 Engineering Enhancements
October 17, 2001 Page 18
HPSUtraining
HP Restricted
Front panel display
ANY
ANY
Activity - Load/Unload
Activity - Read/Write
Tape Loaded - Unit Offline
Media Caution
Fault
Self-test in progress
Off
Flashing Greenperiod=1 Second
Flashing Greenperiod=1/2 Second
Green
Amber
Flashing Amberperiod=1 Second
KeyTapeClean / Attention
DDS
Page 19
October 17, 2001
HPSUtraining
HP Restricted
DDS Autoloaders
Entry Level Automation
October 17, 2001 Page 20
HPSUtraining
HP Restricted
X: cartridge horizontal movement
Y: cartridge vertical movement
R: magazine rotation
Z: magazine horizontal movement
YY XX
RR
ZZ
DDS autoloader – mechanism-basics
Picker mechanism
Robotics PCB fits
here
October 17, 2001 Page 21
HPSUtraining
HP Restricted
DDS-4 Autoloader – Sample Usage Model
30GBServer
This example illustrates how an automated backup could be set upfor a 30GB capacity server to run for 3 months without manual intervention being required.
DDS
October 17, 2001 Page 22
HPSUtraining
HP Restricted
Appropriate uses for DDS Technology
• 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.
DDS
October 17, 2001 Page 23
HPSUtraining
HP Restricted
Ensuring a trouble free life with your HP DDS drive
• 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%
DDS
Page 24
October 17, 2001
HPSUtraining
HP Restricted
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)
DDS
October 17, 2001 Page 25
HPSUtraining
HP Restricted
Summary of HP DAT advantages over competition
• #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!
DDS
October 17, 2001 Page 26
HPSUtraining
HP Restricted
Hardware Setup
• 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
DDS
October 17, 2001 Page 27
HPSUtraining
HP Restricted
Real-World Performance:Transfer Rates on a partially loaded server
Whatever the server loading, HP SureStore DAT40 is still the best performer.
The biggest factor affecting performance is the behaviour of the operating system and other processes running at the same time.
But...
DDS
8.9212.24
14.2016.10 17.20
0.00
2.00
4.00
6.00
8.00
10.00
12.00
14.00
16.00
18.00
20.00
GB
yte
s /
ho
ur 25% CPU Loading
QuantumDLT 4000
Sony DDS4(SDLT10000)
ExabyteMammoth
Sony AIT HP SureStoreDAT40
8.89 9.06
14.22 15.71 17.20
0.00
2.00
4.00
6.00
8.00
10.00
12.00
14.00
16.00
18.00
20.00
50% CPU Loading
GB
yte
s /
ho
ur
QuantumDLT 4000
Sony DDS4(SDLT10000)
ExabyteMammoth
Sony AIT HP SureStoreDAT40
October 17, 2001 Page 28
HPSUtraining
HP Restricted
183 192 186
326
152
0
50
100
150
200
250
300
350
Seco
nd
s
Average data file restore time under NT
DDS
October 17, 2001 Page 29
HPSUtraining
HP Restricted
Summary
• 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
DDS
Page 30
October 17, 2001
HPSUtraining
HP Restricted
Digital Linear Tape
DLT, DLT-VS80 and SuperDLT
October 17, 2001 Page 31
HPSUtraining
HP Restricted
DLT objectives
• 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
DLT
October 17, 2001 Page 32
HPSUtraining
HP Restricted
HP DLT Family - introduction
• 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
DLT
October 17, 2001 Page 33
HPSUtraining
HP Restricted
DLT roadmap
1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002
100GB
50GB
DLT2000
DLT7000
DLT4000
DLT2000XTDLT600
DLT8000
data capacity
GB(native)
DLT-1 DLT VS80
40GB 6MB/s
35GB 5MB/s 40GB 3MB/s
current products
DLT
October 17, 2001 Page 34
HPSUtraining
HP Restricted
HP DLT Family of products
SMART Storage
products
Enterprise servers
DLT8000
SD class
V ,N, L
and A
Mid Range & High End
Intel servers
SureStore DLT80
SureStore products
Workstations, entry level Intel servers
DLT-1 and DLT-VS80
SureStore productsDLT
October 17, 2001 Page 35
HPSUtraining
HP Restricted
HP DLT rack solutions
SureStore Tape Array 5300
SureStore Tape Array 5500
rack solutions for PA-RISC, ia32 and ia64 servers
September ‘01
DLT80m
Ultrium 230m
DAT24m
DAT40m
DVD ROM m
Ultrium 215m
module options
DLT VS80m
TA5300
& TA5500
TA5300
only
DLT
HPSUtraining
HP RestrictedPage 36October 17, 2001
DDS
DAT40
DAT24
DAT40
DAT24
DLT Ultrium
Mid-range servers:LH3000L-class
Mid-range servers:LH3000L-class
Entry level servers:E800A-class
Entry level servers:E800A-class
Enterprise servers:LH6000N-classSuperdome
Enterprise servers:LH6000N-classSuperdome
DLT80
DLT-1
DLT-VS80
DLT80
DLT-1
DLT-VS80
Ultrium215230
HP current DLT portfolio positioning
DLT
October 17, 2001 Page 37
HPSUtraining
HP Restricted
What is DLT?
•Linear tape recording•Data is written in linear tracks down the tape
•The read-write head moves vertically to change tracks
•Helical scan recording•Rotating read-write heads
•tape wrapped around drum
•drum is set at an angle to the tape
head rotation
90° drum wrap
DLT
October 17, 2001 Page 38
HPSUtraining
HP Restricted
DLT technology features & benefits
• 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
October 17, 2001 Page 39
HPSUtraining
HP Restricted
what is DLT? - basics
•Diagram illustrates typical DLT tape path. Note the single spool cartridge.
DLT
October 17, 2001 Page 40
HPSUtraining
HP Restricted
bottom edge of the tape
top edge of the tape
BOT EOT
read-write head
has 52 positions =
208 tracks total.
DLT– 4 channel linear recordingDLT8000 formats
read-write
head movement
head tilts
DLT
October 17, 2001 Page 41
HPSUtraining
HP Restricted
ScratchArea
CalibrationArea
DirectoryArea Data
BOT EOTLeader Splice
DLT tape layout
• 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
DLT
October 17, 2001 Page 42
HPSUtraining
HP Restricted
BOT
DLT tape III
DLT tape IIIxt
DLT tape IV
2 BOTs
Cleaning tape
2 BOTs
BOT
22.5 Ft
43.5 Ft
43.5 Ft
1 Ft Leader
DLT media recognition system
DLT
October 17, 2001 Page 43
HPSUtraining
HP Restricted
Head Tacho
Interposer/Write Protect Sensor
Take-upspool
Drive Hub
Leader Tape
Link buckling mechanism
BOT/EOT sensor
DLT load and unload
tape cartridge
DLT
October 17, 2001 Page 44
HPSUtraining
HP Restricted
DLT load sequence
1. Locate Edge of Tape
2. Find Calibration Tracks from Bottom of Tape
3. Find Calibration Tracks from Top of Tape
4. Develop Write Currents in Scratch Area
5. Read Directory
6. Erase Directory
7. Stop at BOT
DLT
October 17, 2001 Page 45
HPSUtraining
HP Restricted
DLT performance tips - GENERIC
• 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
DLT
October 17, 2001 Page 46
HPSUtraining
HP Restricted
Drive cleaning
• 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
DLT
October 17, 2001 Page 47
HPSUtraining
HP Restricted
read head elements (4)
write head elements (8)
+/- 9deg
DLT8000 read/write head
DLT7000 and 8000 use
symmetrical phase recording
DLT
October 17, 2001 Page 48
HPSUtraining
HP Restricted
DLT8000 SPR1 recording format
Track 0
Track 1
Track 2
Track 3
Bottom Edge of tape
Tape Direction
Track Width 0.0445mm
DLT8000 symmetrical phase recording
DLT
October 17, 2001 Page 49
HPSUtraining
HP Restricted
DLT8000 head tilt mechanism
DLT
October 17, 2001 Page 50
HPSUtraining
HP Restricted
DLT8000/mechanism
read write
head assemblyDLT8000
cartridge receiver
take up spool
(modified from DLT7000)
guide rollers
tachometer
DLT
October 17, 2001 Page 51
HPSUtraining
HP Restricted
DLT-VS80
DLT7000
DLT8000
HP DLT front panel detail
Tape unload
button
density
select button
DLT7000/8000 LEDs:
write protect tape in use
use cleaning tape operate handle
density
LEDs
DLT
October 17, 2001 Page 52
HPSUtraining
HP Restricted
DLT8000/DLT VS80 technology differences
DLT4000 DLT-VS80 DLT8000
capacity (native) 20GB 40GB 40GB
transfer rate (native) 1.5MB/s 3MB/s 6MB/s
buffer 2MB 2MB 8MB
read write channels 2 4 4
number of tracks 128 168 208
recording method RLL(1,7) RLL(1,7) RLL(1,7)
interface SCSI-2 narrow SE
SCSI-3 ultra wide LVD
SCSI-3 ultra-2 wide LVD & HVD
servo system open loop open loop open loop
data compression DCLZ DCLZ DCLZ
cartridge load manual soft load manual
DLT
October 17, 2001 Page 53
HPSUtraining
HP Restricted
DLT8000/DLT VS80 technology differences
DLT4000 DLT-VS80 DLT8000
read-write head technology
ferrite inductive
thin film MR
ferrite inductive
head positioning system
stepper motor & leadscrew
stepper motor & leadscrew
stepper motor & leadscrew
leader attachment method
standard DLT leader
tapesense technology
standard DLT leader
form factor *extended depth
5¼ full height *
5¼ half height
5¼ full height *
HP OBDR no yes no
diagnostics self-test self-test, Tapealert
self-test, Tapealert
memory in cartridge no no no
media DLTtape™ IV
DLTtape™IV
DLTtape™ IV
DLT
October 17, 2001 Page 54
HPSUtraining
HP Restricted
DLT8000, DLT VS80 compatibility
DLT8000 DLT VS80
reads DLT2000 DLT2000XT DLT4000 DLT7000 DLT8000
DLT4000 DLT-1
writes DLT2000 DLT2000XT DLT4000 DLT7000 DLT8000
DLT-1
media DLTtape III DLTtape IIIXT DLTtape IV
DLTtape IV
DLT
October 17, 2001 Page 55
HPSUtraining
HP Restricted
DLT media and drive compatibility
DLTtape IIIXT DLTtape IV
DLT VS80 not supported
read only DLT4000 20GB read-write DLT-1 40GB*
DLT8000 read-write DLT2000XT 15GB
read-write DLT4000 20GB DLT7000 35GB DLT8000 40GB
*note: DLT VS80 cannot overwrite DLT4000 format
DLT