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Whitepaper:Â EqualLogic TCO Analysis by ESG Lab
This ESG Lab report examines the economic excellence of highly scalable EqualLogic iSCSI storage solutions compared to traditional direct attached storage (DAS), Fibre Channel storage area network (FC SAN), and multi-protocol solutions (defined as systems that provide FC, iSCSI, and NAS connectivity). After testing EqualLogic storage in the lab using an infrastructure encompassing seven generations of EqualLogic hardware, ESG Lab calculated the total cost of ownership (TCO) over five years for an organization requiring 80 raw terabytes of storage capacity using systems available for purchase today.
134 days ago by Dell EqualLogicGetting Back to the Basics of Storage Management
RAID technology also brought with it tools to help manage this new DASD. The combination of hardware technology and software tools enabled storage administrators to manage the storage devices and the growth. The raw cost of RAID DASD became very inexpensive and with it the necessity to "Manage" the devices to the same degree as before. These factors drove the ratio of one storage admin for every two or three terabytes to an unthinkable one storage admin for every fifty terabytes. In some data centers, the ratios are even higher! Although the raw cost of RAID DASD is cheap, today's economic conditions have both management and the IT staff looking at the bigger picture and realizing that the total cost of storage ownership is expensive.
210 days ago by BMC SoftwareGrowth Solutions for Data Storage: Meeting the Needs Now and in the Future for Small Business
Businesses of all sizes should look to implementing storage solutions that offer growth and expansion capabilities as their organization grow. Growing offices, can plan for the future by using any of the four expansion methods; growing by expanding disk capacity, increasing the amount of disks within the RAID volume, or growing in hardware performance. In this paper ideal small business solutions will encompass all four growth expansion methods as they will be the most cost-effective over time and allow for the greatest of options. Synology Disk Stations meet the needs of growing business through any of the four expansion methods.
321 days ago by SynologyClustering of Virtual Disk Design of Clustered Servers for Storage Management
Storage technologies were getting very expensive to place a large number of high capacity hard drives in the servers. A large number of low cost hard drives could be linked together to form a single large capacity storage device that offered superior performance, storage capacity and reliability over older storage solution. Many enterprises are now looking at clusters of high-performance, low cost computers to provide increased application performance, high availability, and ease of scaling within the data center. The basic goal of this paper is the same of developing a system which will provides its client a system that will allow file management functions i.e. uploading and downloading of files to users.
321 days ago by Academy PublisherComprehending the Tradeoffs Between Deploying Oracle Database on RAID 5 and RAID 10 Storage Configurations
Redundant Array of Independent Disks (RAID) technology is used to improve performance and availability of the underlying storage arrays for any application. With RAID implementations, performance is improved by distributing I/O across many physical disks and availability is increased with the data rebuilding capability. But both high availability and high performance comes at a price, which are different for different RAID implementations. Most of the time database and storage administrators ask the age-old question - whether to go with RAID 10 or RAID 5 for their database deployment. Customers struggle to make right tradeoffs between these two RAID implementations for their database deployments. This white paper evaluates different tradeoffs including performance, cost, and availability while evaluating RAID 10 compared to RAID 5.
351 days ago by DellData Recovery and RAID Drives
This paper addresses the recovery of information (user files) from hard drives which have been used in RAID systems. There is a history of successful data recovery efforts when working with drives from RAID systems. RAID systems are unique in that multiple drives can be used to store the data and as the 'R' in the acronym states they are 'Redundant'. This redundancy not only helps the system administrator or IT staff keep the systems running when a drive fails but also aids the data recovery engineer in recovery efforts when multiple drives fail. Simple mirror RAID (RAID 1) recoveries are far less complex than any other as the file structure(s) are intact on a complete physical volume.
356 days ago by CPR ToolsA Highly Accurate Method for Assessing Reliability of Redundant Arrays of Inexpensive Disks (RAID)
The statistical bases for current models of RAID reliability are reviewed, and a highly accurate alternative is provided and justified. This new model corrects statistical errors associated with the pervasive assumption that system (RAID group) times-to-failure follow a homogeneous Poisson process, and it corrects errors associated with the assumption that the time-to-failure and time-to-restore distributions are exponentially distributed. Statistical justification for the new model uses theories of reliability of repairable systems. Four critical component distributions are developed from field data. These distributions are for times to catastrophic failure, reconstruction and restoration, read errors, and disk data scrubs.
382 days ago by Institute of Electrical and Electronics EngineersHP Smart Array P800 and HP MSA60 RAID1+0 2,000 User Cluster Continuous Replication Exchange 2007 Storage Solution
This paper describes a tested configuration for deploying Exchange Server 2007 Enterprise Edition (Exchange) with Cluster Continuous Replication (CCR) supporting 2000 users. The performance results and best practices outlined in this paper provide tested guidelines for configuring Exchange using the HP StorageWorks 60 Modular Smart Array (MSA60) storage enclosures, and the HP Smart Array P800 controller.
533 days ago by Hewlett-Packard (HP)The Mathematics of RAID-6
RAID-6 supports losing any two drives. The way this is done is by computing two syndromes, generally referred P and Q. The algebra used for this is the algebra of a Galois Field, GF(28). A smaller or larger field could also be used, however, a smaller field would limit the number of drives possible, and a larger field would require extremely large tables. GF(28) allows for a maximum of 257 drives, 255 (28 - 1) of which can be data drives; the reason for this is shown in the paper.
624 days ago by ZytorUndetected Disk Errors in RAID Arrays
Though remarkably reliable, disk drives do fail occasionally. Most failures can be detected immediately; moreover, such failures can be modeled and addressed using technologies such as RAID (Redundant Arrays of Independent Disks). Unfortunately, disk drives can experience errors that are undetected by the drive - which the paper refers to as Undetected Disk Errors (UDEs). These errors can cause silent data corruption that may go completely undetected (until a system or application malfunction) or may be detected by software in the storage I/O stack. Continual increases in disk densities or in storage array sizes and more significantly the introduction of desktop-class drives in enterprise storage systems are increasing the likelihood of UDEs in a given system.
625 days ago by IBM
