Backup & Archiving

Data Backup

Data storage and backup, while related, are not the same thing. Data includes; spreadsheets that contain revenue forecasts, emails, payroll files, new graphic designs for advertisements, copies of the bills that have gone out for payment, etc.

Data storage is the collection of this information saved on computers or on external hard drives, such as a RAID box or NAS server. Backing up is the act of deliberately making regular copies of that data and periodically taking them to another location where the data is both safe and easily retrievable.

Every backup system has six essential ingredients

Data
Hardware device to backup data
Software
Backup Process to schedule backup operations
Off-Site location to store backup tapes
Media cartridges/tapes

Selecting a backup system

Most small or mid-sized businesses will choose an autoloader/entry-level library solution or a single tape drive attached to a server. The largest businesses backing up massive amounts of data rely on tape libraries, with multiple drives and cartridges, or disk arrays, or a balanced approach utilising both technologies.

Whether a single tape drive, autoloader/entry-level library solution or enterprise tape library is the best choice depends on a number of factors, including capacity needs and resources.

The main differences between standalone tape drives and autoloaders/entry-level libraries:

Standalone tape drives can be mounted inside a server, run on a tabletop in an external configuration, or purchased in a standard rackmount configuration containing one or two tape drives. A single tape drive attached to or integrated into a server is a simple, cost-effective solution for less data intensive environments. Tape cartridges are inserted and removed by hand.

Autoloaders/entry-level libraries are usually mounted in a standard equipment rack, although they are sometimes placed on a tabletop. Available interfaces are SCSI, USB, SATA or SAS. They automate much of the backup process across multiple tape cartridges. Human intervention is only necessary when inserting and removing tapes from the unit, such as for offsite storage purposes. An autoloader contains a single tape drive, while a library typically has more than one tape drive and has slots for a larger number of cartridges.

Backup Software

Choosing a tape drive or an autoloader/library is only part of a backup solution, a choice also needs to be made as to which backup software will be used to control the device. Software can be simple, backing up just the files on a single server, or it can be complex, protecting multiple servers along with email systems, databases, etc. Some tape drives and autoloaders come bundled with the basic software needed to backup one server, giving a complete backup solution in a single package.

Backup software collects data from various sources, such as PCs and file servers, and writes a copy of that data to the tape media in the backup device. Most companies employ two types of backup: full and incremental. Full backups, which copy and store all available data, are usually performed at the end of the week, since much more data needs to be collected. For an incremental backup, the software detects and collects only data that has changed since the previous incremental backup.

Autoloaders and libraries facilitate both types of backup by responding to commands from the backup software. Backup routines and drive-cleaning regimens can be managed by the backup software, so data can be protected without hassles.

Backup software products from Independent Software Vendors (ISVs) are highly refined and are often optimized to work with specific models of tape drives or autoloaders. ISVs and hardware manufacturers even offer certifications that ensure the software and autoloader will work together flawlessly. Their powerful features, flexibility and simplified management tools easily justify their cost.

Benefits of Automating the Backup Process

“Lights Out” Backups
For best performance and efficiency, backups are typically run overnight, during the 8 hours or so when staff aren't actively using the computer network. If the data to be backed up doesn’t fit on a single tape, the backup software asks for another. In the case of a single tape drive, this means the backup job stops until a new tape is manually inserted, with an autoloader or a library the robot handles this chore and the backup continues to completion.

Tape Rotation
The best way to protect valuable business data is to perform a backup of new data every night, dedicating a separate tape to each week or day of the week. The tapes are “rotated” in sequence, one after another, so that new data doesn’t overwrite older data. Eventually, tapes are removed from the rotation system and stored off-site and a new set of tapes is loaded into the system.

Organization and Data Retrieval
After a period of time organisations may have a large collection of tapes that contain valuable business data. Tape management and the ability to find particular files on one of them become a significant operational challenge. Virtually all autoloaders and libraries include bar code readers, allowing them to automatically read the bar code labels on individual tapes. Since these numbers are cataloged by the backup software, the system knows exactly which tape to read from. If the tape is already in the autoloader or library, the tape selection or file restore happens automatically. By combining the tape management advantages of automation with a comprehensive backup and recovery strategy, lost data can be restored in a fraction of the time vs. a standalone tape drive.

Conclusion
The additional price for an autoloader or entry-level library can be minimal when compared to the administrative overhead associated with manual backups performed on standalone drives.

Backup in Operation

Setting proper backup procedures is critical for maximizing the value of a backup solution. Most backup software will contain recommended procedures, however there are a few simple guidelines:

How often?
Most companies find that a daily incremental backup, with a full backup on the weekend, provides the right balance between data protection and impact on network systems.

Verifying it worked?
Backup software provides a “verify” function. It takes a little longer for the software to check the data on each tape, but this confirms that the data is there when it will be needed.

Disaster recovery strategies
All companies – of all sizes – need to store their backed up data off-site. That way, if there’s an earthquake, flood, fire, theft, virus or other disaster, tapes from the remote location can be returned to restore downed systems.

A backup for the backup process
Customers should make sure that a second person is trained in the backup process in case the primary person is out of the office. That backup tapes are periodically checked and to make sure that proper processes are being followed. When data is missing, it’s usually not the tape drive or the backup software that’s at fault!

Archiving

For many, archiving is solely considered a component of backup and recovery. It is the movement of tapes outside of a library, either to a local shelf or a remote facility for disaster recovery. While this definition is sufficient for backup, it does not fully articulate the value that archiving can provide.

In fact, archiving is a process that exists independent of backup as part of a broader, business level data retention strategy. In this instance archiving is focused on helping customers reduce storage costs by moving data off of higher cost primary disk to a lower cost storage tier.

Archiving is especially critical for rich media, government, science and engineering customers that are experiencing explosive growth in the amount of content they maintain and must keep available for revenue generating projects.

For these customers, and others like them, archiving is not an “offline” process where data is moved to a tape and stored on a shelf. Instead it is a “online/active” process where data is stored in a repository that can be accessed at will for repurposing and revenue generation. To this end, a good archiving strategy provides four key features:

Moves files to lower cost tiers of storage - including tape for maximum cost control
Allows files to be accessed on-demand for revenue generating activities
Hides the movement of files so that users do not have to search for data
Protects and safeguards content as it is moved, so no data is accidentally lost

Combined, these four functions allow customers to manage the cost of growing data repositories without sacrificing or complicating access to data.

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