Page of 10

HP 381513-B21 - Smart Array P800 Controller RAID Technology Brief

Raid 6 with hp advanced data guarding technology.
Hide thumbs
   
RAID 6 with HP Advanced Data Guarding technology:
a cost-effective, fault-tolerant solution
technology brief
Abstract.............................................................................................................................................. 2
Introduction......................................................................................................................................... 2
Functions and limitations of RAID schemes .............................................................................................. 3
Fault tolerance of RAID schemes ............................................................................................................ 5
Cost-effectiveness of RAID schemes ........................................................................................................ 7
Performance of RAID schemes ............................................................................................................... 8
Choosing a RAID level ......................................................................................................................... 9
Summary ............................................................................................................................................ 9
Call to action .................................................................................................................................... 10

Advertising

   Related Manuals for HP 381513-B21 - Smart Array P800 Controller RAID

   Summary of Contents for HP 381513-B21 - Smart Array P800 Controller RAID

  • Page 1

    RAID 6 with HP Advanced Data Guarding technology: a cost-effective, fault-tolerant solution technology brief Abstract.............................. 2 Introduction............................2 Functions and limitations of RAID schemes ....................3 Fault tolerance of RAID schemes ......................5 Cost-effectiveness of RAID schemes ......................7 Performance of RAID schemes ....................... 8 Choosing a RAID level .........................

  • Page 2: Abstract, Introduction

    Abstract RAID 6 with HP’s patented Advanced Data Guarding (ADG) technology is a cost-effective solution for storing large volumes of enterprise data with fault tolerance. Its performance, like that of other RAID levels, depends on the nature of the application. Organizations implementing a large drive array should consider RAID 6 because it can tolerate up to two simultaneous drive failures without downtime or data loss.

  • Page 3: Functions And Limitations Of Raid Schemes

    Functions and limitations of RAID schemes Before creating large arrays with a high number of disk drives or with high-capacity disk drives, IT managers should consider the limitations of available RAID schemes in protecting data during a single- or multiple-drive failure. RAID schemes, called levels, are differentiated by the method each uses to provide fault tolerance.

  • Page 4

    Table 1. Summary of RAID technologies for large arrays RAID LEVELS Function/Applications Limitations Data is distributed Highly vulnerable RAID 0 across separate disk to failure. The drives. entire array will fail if one drive Image Editing • Video fails. Production • Pre-Press Applications Requires a minimum of one drive.

  • Page 5: Fault Tolerance Of Raid Schemes

    Fault tolerance of RAID schemes Often, the terms reliability and fault tolerance are used interchangeably in describing RAID schemes; however, there is a distinction between them. Reliability refers to the likelihood that an individual drive or drive array will continue to function without experiencing a failure. Reliability is typically measured over some period of time.

  • Page 6

    Figure 1. Failure probability for logical drives with four RAID levels and varying numbers of drives in the array...

  • Page 7: Cost-effectiveness Of Raid Schemes

    Cost-effectiveness of RAID schemes The cost effectiveness of each RAID solution is a balance between the total cost of the array and its usable capacity. While the total cost includes all the drives in the array, the usable capacity includes only the drives that store non-redundant (not parity or mirrored) data.

  • Page 8: Performance Of Raid Schemes

    Table 2. Summary of RAID array storage efficiency* RAID 1 RAID 1+0 RAID 5 RAID 6 (ADG) Usable Capacity C * (n/2) C * (n/2) C * (n-1) C * (n-2) (C = capacity of smallest drive; n = number of drives) Minimum number of drives Recommended maximum number of drives*...

  • Page 9: Summary

    Choosing a RAID level To choose the optimum RAID level for data protection in large arrays, IT managers should consider a variety of factors, including: • Fault tolerance (based on availability requirements) • Cost effectiveness (based on storage efficiency or cost per gigabyte of usable capacity) •...

  • Page 10: Call To Action

    To help us better understand and meet your needs for ISS technology information, please send comments about this paper to: TechCom@HP.com. © 2002, 2005 Hewlett-Packard Development Company, L.P. The information contained herein is subject to change without notice. The only warranties for HP products and services are set forth in the express warranty statements accompanying such products and services.

Comments to this Manuals

Symbols: 0
Latest comments: