Browse Prior Art Database

Mobile Disks for System Recovery Disclosure Number: IPCOM000033632D
Original Publication Date: 2004-Dec-20
Included in the Prior Art Database: 2004-Dec-20
Document File: 3 page(s) / 62K

Publishing Venue



This solution will reduce the amount of time taken to recover data at a remote Disaster Recovery (DR) site without having to spend large amounts of money on the required infrastructure associated with a dual site recovery plan. The solution is based on using a duplicate set of data held on disks that are moved around from one location to another like tapes are today.

This text was extracted from a PDF file.
This is the abbreviated version, containing approximately 42% of the total text.

Page 1 of 3

Mobile Disks for System Recovery

Mobile Disks for System Recovery

Recovering the data of a typical data center using traditional tape dumps can take between 24 and 48 hours depending upon the number of tape drives you have access to. This timeframe can be significantly reduced by using dedicated disk subsystems and network links using synchronous and asynchronous transmission modes between devices at the primary data center and the DR site. Solutions such as IBM's* Enterprise Systems Storage (ESS) can use Peer to Peer Remote Copy (PPRC) or Extended Remote Copy (XRC) although these solutions are costly. Solution Overview

    The Disk Subsystem is broken down into disk draw unit pairs (One primary Redundant Array of Independent Disks (RAID) disk draw, permanently allocated to the disk controller and a secondary RAID disk draw, which is optional), the controller can use either the primary disk or secondary disk draw. The secondary RAID draw can be removed at any synchronisation point and transported offsite like a group of tapes. The synchronisation point is taken at a system level so that recovery can be made to a single point in time, at the DR location the disk draws are simply slotted into the free slot alongside the primary disk draws, which are connected to the controller and the need for data restoration time is negated. The secondary disk can be used immediately to bring up the system and in the background the secondary disks are copied to the primary disks so the secondary can be used for their primary purpose of backup or recovery.

The main advantages of this are:
· The time to recover your system significantly reduced;
· There will be a reduction in media recovery problems associated with tapes;
· Backup and recovery of data is completed at a subsystem level, which makes the backups much more reliable;
· There are less devices to transport and manage;
· This invention can be also be used for servers that contain internal disk on midrange and Intel servers;
· The cost of such a recovery is just the cost of the disk hardware and a duplicate controller at the DR location, network connections from the primary and recovery site are not required;
· The size of the disk subsystem can be expanded or reduced depending upon the number of disks you wish to connect to it;
· Traditional database log recoveries can then be applied to these disks as you would for tape recoveries.

    The following subsections describe how the invention works and it is based on the current IBM ESS (Enterprise Systems Storage) as it is today with IBM ESS Flashcopy** like functionality. It is important to note that this invention can be used across all disk subsystems:
The Primary Disk Frame: will have an external slot below each primary RAID draw, this slot is used to add and remove the secondary RAID draw. Once a secondary disk is inserted into a slot, it is not activated until the enable button is pressed; this is located next to the secondary disk array slot...