Even with today's strong hardware and self healing file systems there is always a chance for data to go missing. A hard drive crash or other hardware problem could prevent you from accessing data on your workstation or server. Users sometimes accidentally delete files and realize it later, much to their horror. Perhaps you need to have a snapshot of your critical files in an offsite location to act as a business continuity measure or need to move some of your files from active storage to an archive to free up space in your environment. New laws have been passed that require email to be saved for a number of years in certain industries. A proper backup and archiving solution will help you manage all these issues.

With the introduction of Mac OS X Leopard, Apple has given users a wonderful and easy to use incremental backup solution - Time Machine. Time Machine uses an external hard disk connected to your workstation to maintain historic snapshots of your entire file system and for you to retrieve a file that was deleted or to restore your entire computer easily by booting from the Leopard DVD. The cost of external disk drives is very reasonable and Time Machine is included in OS X Leopard. Time Machine is designed to be a stand alone backup solution for single computers. If your needs require backup of multiple computers in a business environment a different solution is required. For this type of scenario I recommend EMC Insignia's Retrospect 6.1. The main Retrospect application is installed on one computer which will act as the backup server, and the Retrospect Client is installed on the other computers in your network. The Retrospect software will poll the network and backup data from your client computers to a tape drive or external hard drives attached to the main computer. When backing up multiple computers it is normal to only select the critical data like email, desktop files and working directories such as your photos, music or documents directories rather that the entire file system to conserve the disk space. EMC has announced a new version of Retrospect to be released soon, Retrospect X, but the actual release date is unknown at this point. 

Backups should be scheduled daily if the amount of data to backup is normal. If there is a large amount of data causing the backup to take more than 8 hours the backup can be scheduled for a weekend or to occur 2-3 times per week rather than daily. It is recommended to rotate your backup media either every week or 2 weeks to avoid losing backup data to hardware problems and to allow part of your backup data to be kept offsite, adding to your insurance. 

In the past, tape drives were used exclusively as backup media, but now hard disk drives are inexpensive enough to maintain several as your main backup destinations. There are pros and cons to each media type. Hard disks are easily connected and have very fast read and write speeds. The problems with hard disk drives is that they can be damaged in transit or the mechanisms that spin the drive can wear out and cause the drive to not be readable. Tape drives are expensive up front, but over time the low cost of the tapes will begin to equalize the cost per gigabyte of storage. Tapes are a reliable media for backup and archive and are much less likely to be damaged in transit or fail mechanically. Tapes can have slower access speeds and require someone to put the cartridge in the drive.

A very good backup solution uses rotating hard drives for the quickly restorable or online backup access and tapes for archiving snapshots of your data. 

In my experience, backups that are automatic and unattended are the best solution. We all have busy lives and it is easy to forget to manually backup your data. Let Mazaroth IT Consultants help you find the best solution to your backup needs.