-
Hitachi 9900 Series - page 1
...
-
Hitachi 9900 Series - page 2
i ...
-
Hitachi 9900 Series - page 3
H itachi Data Systems ii ...
-
Hitachi 9900 Series - page 4
T able of Contents T able of Contents ......................................................................................................................................iii T able of F igures ........................................................................................................................................vii T able of T abl ...
-
Hitachi 9900 Series - page 5
Adv anced Cache Algorithms of the Lightning 9900 Series ......................................................................18 H itachi F lashAccess Allows Datasets to be P ermanently Placed in Cache ................................................18 R ead-ahead for H igh-performance Sequential Reads .............................................. ...
-
Hitachi 9900 Series - page 6
Chapter 9 – The Lightning 9900 Series Software Solutions Ar e the Best in the W orld ______________33 I ncreased IT service levels in availability and performance through B usiness Continuity Planning (BCP) software and services ......................................................................................................................3 ...
-
Hitachi 9900 Series - page 7
H itachi N anoCopy Implementation Service ......................................................................................46 Continuous A vailability Service ........................................................................................................47 O n-line Data Migration S er vice ............................................. ...
-
Hitachi 9900 Series - page 8
vii T able of F igur es F igure 1 The 9960 provides for exploding gr owth and data consolidation while the 9910 provides for managed gr owth and open system exploitation. ................................................2 F igure 2 The Hitachi Lightning 9960 S eries ’ Hi-S tar internal switched-fabric architecture. ................3 F igure 3 Syst ...
-
Hitachi 9900 Series - page 9
H itachi Data Systems viii T ables T able 1 Comparison of the Lightning 9900 series models. ................................................................2 T able 2 Bandwidth of supported interfaces of the Lightning 9900 Series. ......................................14 T able 3 System Capacities and N umber of disk drives for various configuratio ...
-
Hitachi 9900 Series - page 10
1 I ntroduction The Only Switched-Fabric Storage Architectur e in the World The Hitachi F reedom S torage ™ Lightning 9900 ™ S eries internal switched-fabric storage architecture is consider ed the most advanced design available in the world for open systems and mainframe data. The patented Hi-S tar ™ architecture po wers the most intelligent ...
-
Hitachi 9900 Series - page 11
Product Characteristics 9960 9910 Number of Cabinets 2-7 1 Maximum Cache Capacity 32 GB 16 GB Number of Fibre Channel/ESCON ® Ports Up to 32 Up to 24 Number of FICON Ports Up to 16 Up to 12 Number of Disks (HDDs) Up to 512 Up to 48 Number of Array Groups Up to 126 Up to 11 Number of ACP pairs 1-4 1 Number of FC-AL Paths to Back-end Disks Up to 32 ...
-
Hitachi 9900 Series - page 12
At the heart of the Lightning 9900 ™ S eries ’ enormous capacity for throughput lies the Hi-S tar ™ architecture. This network of interconnecting high-speed links to system components provides an unequaled internal aggr egate bandwidth of 6.4GB/sec (gigabytes/sec) in the 9960. This bandwidth is divided equally into 3.2GB/sec for data transfer ...
-
Hitachi 9900 Series - page 13
Comparison to the Shared Bus Ar chitecture of the Hitachi Freedom Storage ™ 7700E U nlike the shared common bus architecture of previous generation storage products, such as the 7700E (as shown in F igure 3 for reference to a shar ed bus architecture), H i-S tar ™ is designed to truly scale in both capacity and per formance. This is possible on ...
-
Hitachi 9900 Series - page 14
Other Information Sources A vailable from Hitachi Data Systems ® A dditional information on the enterprise storage market, including an in-depth ov er view of the technically advanced and unsurpassed software solutions available from H itachi, is available in the companion publication, the H itachi Software Solutions G uide . This document is down ...
-
Hitachi 9900 Series - page 15
H itachi Data Systems 6 ...
-
Hitachi 9900 Series - page 16
7 The Lightning 9900 S eries Pa ckaging Model 9960 Packaging The Lightning 9960 ™ is available in a two to seven cabinet configuration (as shown on the cover of this guide), depending on connectivity and capacity needs. A Contr ol F rame serves as the control center of each system and manages up to six Array F rames that are connected via high sp ...
-
Hitachi 9900 Series - page 17
Model 9960 Array Frames Array frames 1-4 of the 9960 contain up to 96 Hard D isk Drive Assemblies (HDDs) and communication interfaces to the Control F rame. Array frames 5-6 contain up to 64 drives for a total of 512 drives for a maximum configured system. An Array F rame is shown in F igure 5. This design allows for efficient centralized and conso ...
-
Hitachi 9900 Series - page 18
Cables carry 48-volt main system power from the back of the Control F rame and Array F rame where the power is converted to the required v oltages. D ifferent A C power cord options allow all Lightning 9900 ™ S eries models to connect with the different electrical outlet configurations used around the world. Model 9910 Packaging Although the 9960 ...
-
Hitachi 9900 Series - page 19
The System Monitoring Network of the Lightning 9900 ™ Series The Lightning 9900 ™ S eries systems are designed with a system-monitoring networ k. The system monitoring cables are connected to all cabinets in the Lightning 9900 Series systems, and report a variety of system parameters, such as component failure, fan speed, power , voltages, and ...
-
Hitachi 9900 Series - page 20
11 Fr ont-end Design of the H itachi Lightning 9900 S eries CHIPs Support Fibre Channel Host and ESCON ® or FICON Host Connectivity and Scalability The Lightning 9900 ™ S eries supports both F ibre Channel for open systems and ESCON ® or FICON for S/390 ® compatible platforms as shown in F igure 8. 3 F igur e 8 – Fibr e Channel and ESCON ® ...
-
Hitachi 9900 Series - page 21
About the Fibre Channel Interface Boar ds Each F ibre Channel Interface Board, as shown in F igure 9, has four Interface Pr ocessors 2 for management of connectivity to the host. F igur e 9 – A Fibr e Channel host adapter board and its major hardwar e components. H itachi Data Systems 12 2 The Lightning 9900 ™ Series uses the Reduced Instructio ...
-
Hitachi 9900 Series - page 22
There are four ports for each interface board or a total of 32 host interfaces for a fully configured system. An ESCON interface board is sho wn in F igure 10. A FICON interface board has a similar appearance. A Lightning 9900 ™ S eries system can connect to mainframes and open systems hosts, thereby consolidating the storage for an enterprise un ...
-
Hitachi 9900 Series - page 23
Bandwidth of Supported Host Interfaces The bandwidth of interfaces supported by the Lightning 9900 ™ S eries is shown in T able 2. Supported Interface Bandwidth Fibre Channel Adapters 100MB/sec or 200MB/sec ESCON ® Adapters 17.5MB/sec FICON Adapters 100MB/sec Number of Host Interfaces Supported Up to 32 Fibr e Channel, ESCON ® or FICON ports ar ...
-
Hitachi 9900 Series - page 24
15 H i-S tar Architectur e – An I nternal S witched H ierarchical S tar N etwork The Internal Hi-Star Architecture The internal Hi-S tar architecture consists of two separate networks, the Cache H ierarchical S tar Networ k (C-HSN) and the Control M emory Hierarchical S tar Network (CM-HSN). The Cache Hierarchical Star Network The C-HSN is the ne ...
-
Hitachi 9900 Series - page 25
The Cache Switch Provides Non-blocking Switched Access to Cache At the heart of the C-HSN is the Cache Switch (CSW). T ogether , these four switches (in the 9960) form the internal start using parallel switch fabric bus (PSFB) of the C-HSN. The CSW is a specially designed crossbar switch that functions as a combination MUX, path arbitrator , and no ...
-
Hitachi 9900 Series - page 26
In a shared bus storage system, the number of internal simultaneous processor operations that can occur is equal to the number of buses on the backplane. The shared buses are used by all host channels to communicate between the pr ocessors on the host adapters and cache memory . In the case of the shared-bus design shown in F igure 14, there are fo ...
-
Hitachi 9900 Series - page 27
The 9960 Provides 32GB of Fully Addr essable Cache The 9960 supports up to 32GB of data cache, all directly addressable. Separate cache modules (up to 1.5GB) are used for control storage. Competitive systems use their cache for both data and control information, limiting the amount of usable data cache. Advanced Cache Algorithms of the Lightning 99 ...
-
Hitachi 9900 Series - page 28
control memory in its “ split” configuration. Again, control memory is mirrored. This path topology is used to facilitate this mirrored architectur e. E ither way the bandwidth is calculated in the CM-HSM, the bandwidth is 3.2GB/sec total when all of the processor modules are installed. 4 bits clocked at 100MHz equals 50MB/sec per path multipli ...
-
Hitachi 9900 Series - page 29
H itachi Data Systems 20 ...
-
Hitachi 9900 Series - page 30
21 H igh P erformance Back-end D esign High-speed Back-end Design Ne w Hitachi high-performance back-end drives ar e available with the Lightning 9900 ™ S eries. The drives are attached via F ibre Channel – Arbitrated Loops (FC-AL). Eight 100MB/sec FC-AL connect to dual ported drives for each ACP pair . With four configured A CP pairs installed ...
-
Hitachi 9900 Series - page 31
These new dual-ported/dual-active F ibre Channel disk drives, combined with the technology built into the ACP pair , allow the back end of the Lightning 9900 ™ S eries to use all eight FC-AL paths in an ACP pair for both performance and fault tolerance. Ho weve r, no one disk or array group can use both paths simultaneously . The ACP s monitor th ...
-
Hitachi 9900 Series - page 32
23 Capacities and RAID Architectur e Storage Capacity of the Lightning 9900 ™ Series The Lightning 9900 ™ S eries supports an unmatched range of capacities as shown in T able 3. System Capacities and Number of disk drives for various configurations Raw System Raw capacity with Raw capacity with Raw capacity with Configuration 18GB drives 73GB d ...
-
Hitachi 9900 Series - page 33
High-density Disk Drive Assemblies (HDDs) The disk drives used in the Hitachi Lightning 9900 ™ S eries are specially designed for high availability and performance by Hitachi Limited. Each driv e has the industry unique featu r e of suppo r ting dual acti v e po r ts. This provides significantly increased performance. F igur e 20 – The L ightni ...
-
Hitachi 9900 Series - page 34
H itachi H igh-A vailability S oftware I mpro ves A pplication Ser vice Levels An Overview of High-Availability (HA) Computing Softwar e It is increasingly important for a business to support continued access to global information 24 hours a day , 7 days a week. What ’ s more, careers often depend on the availability of service levels provided by ...
-
Hitachi 9900 Series - page 35
• Dual data paths and dual control paths connecting every component. • Mirror ed cache for all write data instead of single image cache. 3 • GDPS support. • Hitachi T rueCopy combined with ShadowI mage ™ for disaster recov ery . •H itachi N anoCopy ™ to provide P oint-in-T ime copies without requiring quiescence of databases or applic ...
-
Hitachi 9900 Series - page 36
There are four basic types of high-av ailability middleware that can reduce downtime in the event of a data path or host failure. The Lightning 9900 ™ suppor ts each classification of middleware: 1. Alternate Pathing middleware switches the I/O load in the event of path failure This type of middleware automatically switches the I/O load on a fail ...
-
Hitachi 9900 Series - page 37
4. Parallel Database Clustering This type of middleware is a special version of host failo ver middleware, which supports major parallel database ser vers like Oracle ® P arallel Server , Informix ® XPS, and Sybase ® MPP . Clustering middleware supports distributed lock management, a feature that enables parallel database software running on sep ...
-
Hitachi 9900 Series - page 38
H itachi H igh A vailability Softwar e Improv es Application S ervice Levels 29 Standard Redundant Fans for Cooling The Lightning 9900 ™ provides fully r edundant fans for uninterrupted cooling to all components of the system. The speed and operation of these fans are monitored by the environmental monitoring system. If a fan should fail, it can ...
-
Hitachi 9900 Series - page 39
Hi tachi Data Systems 30 ...
-
Hitachi 9900 Series - page 40
31 Pe r formance Considerations T ruly Scalable Performance B ased on the internal switched-fabric H i-S tar ™ architecture, the Lightning 9960 ™ shows unmatched performance scalability . The mor e capacity and connectivity added to the 9960, the more total bandwidth increases. As stated pr eviously , the 6.4GB/sec internal bandwidth is reached ...
-
Hitachi 9900 Series - page 41
Internal Switching Overcomes the Limitations of Shared Bus Ar chitectures It can be seen from F igure 24 that a reduction occurs in the OL TP per formance for the shared bus architectur e of the 7700E system. This occurs at P oint 1, when the DSS application begins at about 45 minutes into the test. It depicts the effect that the DSS application (f ...
-
Hitachi 9900 Series - page 42
33 The Lightning 9900 S eries S oftware S olutions Ar e the B est in the W orld C ustomers and analysts r egard the H itachi Freedom S torage Lightning 9900 ™ S eries as the most advanced products in the enterprise storage system market. The S oftware S olutions Guide discusses the advantages of this suite of leading-edge software products that e ...
-
Hitachi 9900 Series - page 43
The Hitachi F reedom S torage ™ software solutions for Lightning 9900 ™ Seri es systems support an enterprise’ s strategic goal of accessing any information, on any computer , located anywhere, at any time. The many advanced functions available on Lightning 9900 Series ™ hardware ar e initiated, managed, and controlled through these powerfu ...
-
Hitachi 9900 Series - page 44
To this already robust platform, H itachi Data Systems adds a number of solutions to ensure quick reco ver y from acts of nature, human errors, application errors, and malicious attacks. In the world of e-commerce, it is no longer enough to have a backup copy of one ’ s data; businesses must also plan for rapid reco very from such outages. Hitach ...
-
Hitachi 9900 Series - page 45
Business Goals served by Copy Software W orldwide commerce and industry have become increasingly dependent on IT r esources to conduct business. E ven a temporary loss of critical applications or data access can cause serious economic impact to a company , and an extended outage can threaten a company ’ s existence. Regulatory and competitive pre ...
-
Hitachi 9900 Series - page 46
Centralized and O pen S ystems Management S oftware S implifies IT O perations A powerful and open systems management philosoph y The Hitachi F reedom S torage ® software solutions support an enterprise ’ s strategic goal of helping customers focus on their business issues instead of on deploying enabling technologies by pro viding powerful cent ...
-
Hitachi 9900 Series - page 47
H iCommand ™ is an important H itachi management tool in that it provides a comprehensive storage management softwar e framework that enables an enterprise to manage all supported Hitachi storage products and many H itachi software solutions: 1. H i Command ™ for storage management including alerts, configuration parameters, LUN mapping. 2. H i ...
-
Hitachi 9900 Series - page 48
The components of H i Command ™ H iCommand ™ consists of thr ee components: 1. The H iCommand ™ Ser ver r esides on any Windows ® NT/2000, or S un S olaris server , and connects to the Lightning 9900 ™ S eries system(s) o ver a private L AN. A single HiCommand ™ server can manage multiple Lightning 9900 ™ S eries storage systems, provi ...
-
Hitachi 9900 Series - page 49
Hitachi Resource Manager ™ 9000 The following is a summary list of the many ways in which the Hitachi Resour ce M anager ™ can simplify IT operations, impro ve availability and performance ser vice levels for business critical OL TP and DSS applications, and thereby enable the more rapid deployment of new applications by managing data more inte ...
-
Hitachi 9900 Series - page 50
information at the touch of a button. The robust GUI-oriented command screen for H itachi G raph-T rack ™ is shown in Figur e 26. Running on a PC attached to a dedicated L AN, Hitachi G raph-T rack ™ displays real-time or historical data for all connected Lightning 9900 ™ systems, helping users identify important peaks in utilization and ongo ...
-
Hitachi 9900 Series - page 51
H itachi L UN Manager also features logical unit size expansion that dramatically improv es LUN flexibility . Up to 36 physical L UNs can be presented to the operating system as a single, large LUN. This capability simplifies storage management because there are fewer L UNs to manage. T wo levels of password protection, user and administrator , ens ...
-
Hitachi 9900 Series - page 52
43 Centralized and Open Systems M anagement Software Simplifies IT O perations Storage Maximizer The Hitachi S torage Maximizer ™ is a solution that uses two software products – H itachi CruiseControl ™ and H itachi FlashAccess ™ software for mainframes and open systems. This allows customers to manage the cost of storage, as data is consol ...
-
Hitachi 9900 Series - page 53
Hi tachi Data Systems 44 ...
-
Hitachi 9900 Series - page 54
Pr ofessional Ser vices and S uppor t Hitachi Data Systems ® is consistently ranked Number One in the Industry In numerous independent sur veys on IT services organizations, Hitachi Data Systems ® continually wins the highest ratings in terms of overall customer satisfaction. “S er vice R esponsiveness ” is the key Hitachi Data S ystems ® ch ...
-
Hitachi 9900 Series - page 55
order to protect it. The Data Protection S er vices team uses software in all three categories of data movement: 1) Data Migration 2) Real-T ime Copy 3) P oint-in-T ime Copy The team will perform data relocation and migration tasks that establish rock-solid backup and disaster reco very copy facilities to keep a business running in the event of man ...
-
Hitachi 9900 Series - page 56
Continuous Availability Service K eeping critical systems available at a level 4 or 5 on the Scale of 9s is no easy task. I t involves the best of har dware, software, and operations practice. H itachi Data Systems ® professional services experts review the entire backup and recove ry software portfolio, operations procedures, and har dware config ...
-
Hitachi 9900 Series - page 57
H itachi Data S ystems ® offers an entire suite of professional services that will assist clients in planning and implementing Storage Ar ea Network (SAN) solutions to optimize management and control data across the enterprise. The modular services include: • The SAN Enterprise Infrastructure Assessment (EIA) S ervice • The SAN Strategic and T ...
-
Hitachi 9900 Series - page 58
49 S ystem Configurations for the P er formance E xperiment Configurations of the HP and Sun Servers and Configurations of the Lightning 9960 ™ Switched Architectur e to a Shared-bus Architectur e like most competitive products for the Performance Experiment In the performance test discussed in Chapter 8, comparing each application resided on its ...
-
Hitachi 9900 Series - page 59
differences between the 7700E and the Lightning 9960 ™ system for the DSS workload; • The 7700E used all 6GB drives. • The Lightning 9960 ™ system used a mix of 18GB and 47GB drives. H itachi Data Systems 50 ...
-
Hitachi 9900 Series - page 60
51 G lossar y of T erms 10BaseT E thernet with a data transfer rate of 10Mbits/sec. 100BaseT Also known as F ast Ethernet with a data transfer rate of 100Mbits/sec. AG Array Gr oup. ACP Array Control P rocessor . The group of processors on a PCB that performs the physical access of the disk drives across four FC-AL loops. AC P pair A combination of ...
-
Hitachi 9900 Series - page 61
communication is an exactly timed stream of bits when the start of a character is located by using a clocking mechanism such as bipolar encoding. See also S ynchronous, H itachi T r ueCopy ™ . Av ailability In computer science, availability refers to the degree to which a system or resour ce is capable of performing its normal function. A vailabi ...
-
Hitachi 9900 Series - page 62
CARB Cache memory Arbitrator circuit. Hitachi designed logical circuit in the Cache S witch (CSW) used to arbitrate access to cache. C ache Cache (pronounced cash) can be either on-chip memory circuits in a microprocessor (e.g. L2 processor cache), a reserved section of main memory (e.g. system or ser ver cache), or an independent, high-speed disk ...
-
Hitachi 9900 Series - page 63
Consistency Gr oups A software copy technique of suspending multiple volumes at the same time. Control F rame The Disk Controller or control frame, is the center cabinet of the Lightning 9900 ™ S eries system, housing the channel switch, cache, pow er supplies, batteries, and host interface cards. C ORA (Cost of Risk Analysis) CORA is a unique, s ...
-
Hitachi 9900 Series - page 64
DD D isk Dir ector . D ata Duplication S oftware that duplicates data as in r emote copy or P oint-in-T ime (PiT) snapshots. D ata duplication is differentiated from data migration in that with data duplication at the end of the process there ar e two copies of data and with data migration there is only one. D ata Migration S oftware that migrates ...
-
Hitachi 9900 Series - page 65
EBCDIC A bbreviation of E xtended Binary-Coded Decimal Interchange Code. P ronounced eb-sih-dik, EBCDIC is an IBM ® code for representing characters as numbers. Although it is widely used on large IBM ® computers, most other computers, including PCs and Macintoshes ® , use ASCII codes. See also ASCII, binary , synchronous, and asynchronous. El e ...
-
Hitachi 9900 Series - page 66
F ailover H ost, host bus adaptor , cable, or controller failover is the r outing of all transactions to a second controller when the first controller fails. F ast Ethernet F ast Ethernet or 100BaseT , defined by the IEEE 802.3 standards committee, pr ovides a 100 Mbps standard that is compatible with existing 10B aseT installations, preserving the ...
-
Hitachi 9900 Series - page 67
log in with each other and the switch to exchange operating information on attributes and characteristics. This information includes port names and por t IDs and is used to establish interoperability parameters. FICON An ESA/390 ® computer peripheral interface. F ile B ackup The practice of copying a file that is stored on disk or tape to another ...
-
Hitachi 9900 Series - page 68
r un concurrently . Reliability is enhanced with retry logic, alternate path routing, and r estart from point of failure. Ease of use is pro vided by a Java-client interface, a system monitor , scheduling support, and remote control of client functions from OS/390 ® . HDD H igh-density disks. U sed in the Lightning 9900 ™ S eries. HDmS The Hitac ...
-
Hitachi 9900 Series - page 69
storage ports, multiple cache nodes, and multiple disk Array Control P rocessors (ACP s). Each path runs at 100MB/s, permitting the Lightning 9900 ™ to scale up to a total bandwidth of 6.4 GB/s. This is six-to-eight times the internal bandwidth of shared bus based storage systems. F or redundancy and performance, Hi-S tar ™ consists of four cac ...
-
Hitachi 9900 Series - page 70
Hi tachi Rapid Recov er y The Hitachi Rapid R ecovery solution for S/390 ® -attached storage combines Hitachi N anoCopy ™ , Hitachi T rueCopy-S/390 Asynchronous ™ , and Hitachi S hadowImage ™ . This facility enables data to be copied from one set of S/390 ® -attached systems to another with complete transaction integrity and without disrupt ...
-
Hitachi 9900 Series - page 71
HSN H ierarchical S tar Networ k. The technical term used to describe the combined internal networks (the C–HSN and the CM–HSN) of the Lightning 9900 ™ S eries. Hub A common connection point for devices in a F ibre Channel network. A hub contains multiple ports. When a F ibre Channel packet of data arrives at one port, it is copied to the oth ...
-
Hitachi 9900 Series - page 72
Lightning 9900 ™ S eries The Lightning 9900 ™ S eries was announced in J une 2000 (Lightning 9960 ™ ) and Nov ember (Lightning 9910 ™ ). It r epresents a major advance in enterprise-class storage systems with its Hierarchical S tar Networ k switched internal architecture, which provides for many times mor e simultaneous transfers to and fro ...
-
Hitachi 9900 Series - page 73
MBCP M aster Business Continuity P rofessional. The highest level of professional certification of the Disaster Reco ver y Institute (DRI). The master level targets an individual with a minimum of five years of experience as a business continuity/disaster reco ver y planner . S ee also DRI (Disaster R ecovery Institute), CBCP (Certified Business Co ...
-
Hitachi 9900 Series - page 74
MTBF M ean Time B etween F ailure. A commonly used measure of system r eliability , usually expressed in hours. M odern disk drives typically have an MTTR of 1 million hours or more. MTTR M ean Time T o Repair . Includes the time taken to diagnose the failure, replace or repair faulty component(s) and restart the system so it is available to users. ...
-
Hitachi 9900 Series - page 75
O n-line system An interactive computer system supporting users over a networ k of computer terminals. O pen system A system whose characteristics comply with standards made available thr oughout the industry , and therefore can be connected to other systems that comply with the same standards. Op erating System The operating system is the most imp ...
-
Hitachi 9900 Series - page 76
RAID R edundant Array of Independent D isks. RAID is used to increase the reliability of disk arrays by pro viding redundancy either through complete duplication of the data (RAID-1, i.e., mirroring) or through construction of parity data for each data stripe in the array (RAID-3, -4, -5). RAID-5, which distributes parity information across all dis ...
-
Hitachi 9900 Series - page 77
SCSI Sm all Computer System Interface. An intelligent bus-level interface that defines a standard I/O bus and a set of high-level I/O commands. There are currently many flavors of SCSI defined by different bus widths and clock speeds. The seven major va riations of SCSI are SCSI 1, SCSI 2 (F ast/Narr ow), SCSI 2 (F ast/Wide), Ultra SCSI (F ast/Narr ...
-
Hitachi 9900 Series - page 78
S ynchronous S ynchronous communications occurs when the transmission of data between two devices is synchronized with a clocking scheme or other technique. The sender and r eceiver need to synchroniz e with one another before data is sent. In synchr onous communication the bit stream and the clock pulse are synchr onized by a special bit transitio ...
-
Hitachi 9900 Series - page 79
W AN Wi de Area N etworks or W ANs are networks of computers that are geographically dispersed and connected by radio waves, telephone lines, satellites, or high-speed fibre optic backbones. Wa rm site An alternate-processing site that is only partially equipped (as compared to H ot site which is fully equipped). See also H ot site and Cold site. W ...
-
Hitachi 9900 Series - page 80
Hi tachi Data Systems W orldwide Offices www .hds.com www .storage@hds.com Corporate Headquarters 750 Central Expressway S anta Clara, California 95050-2627 U.S.A. (408) 970-1000 info@hds.com A sia Headquarters 39-09 T ower One Lippo Centre 89 Queensway H ong K ong 2525-2385 infoasia@hds.com A ustralia/N ew Zealand Headquarters 11-17 Khartoum Road ...
Do you have a question concerning Hitachi 9900 Series?
Use the form below
If you did not solve your problem by using a manual Hitachi 9900 Series, ask a question using the form below. If a user had a similar problem with Hitachi 9900 Series it is likely that he will want to share the way to solve it.