Disk Backup, Disk to Disk Backup
Disk backup has been making a name for itself this past year especially since costs continue to drop. More and more people are seeking answers on the best way to implement disk-to-disk backup and even disk-to-disk-to-tape. We tapped our own experts as well as other industry experts to put together this guide for you. A few of the topics covered are the cost of integrating and implementing disk backup, how the technology works with iSCSI SANs, hot disk-to-disk products and a peak into how and why some managers are going with disk backup.
Faster performance is one good reason to consider moving from tape to disk for your backups, but it’s not the only reason. Anyone who’s ever worked much with magnetic tape of any kind knows that it’s fragile. Tape breaks, it’s vulnerable to environmental factors such as humidity and heat, and it loses tension. Tape drive heads get dirty and have to be cleaned, and data isn’t always restored perfectly due to these and other factors. Some experts estimate that from 25% to 50% of tape restorations fail, at least partially.
Disks are more durable than tape. They last longer, and they hold up under more frequent overwriting. Because they are contained inside sealed cases, there is less chance of the media being affected by the external environment. Of course, they never require retensioning or head cleaning.
Finally, disk backups are easier to manage. Keeping up with a collection of tape cartridges can become a logistical nightmare. Disk backup systems typically include management tools, often browser-based so you can easily configure settings and check status from anywhere.
Disk-to-disk backup is a very attractive solution, especially with the introduction of several new inexpensive disk options like ATA and Serial ATA (SATA).
The best way of backing up disk to disk is to back up your data to someone else’s disk; that is, use an Internet based backup service and store your backed up data on the service’s remote server. These services provide for easy off-site storage of your backup data, while it remains easily available when you need it.
Companies that provide online backup services generally build multiple redundancies into their systems and often provide 24/7 staffing and monitoring. They often use “data vaults," so that your backed up information is physically secured within windowless rooms with reinforced concrete walls and redundant power supplies backed up by generators, to withstand natural disasters. Facilities are guarded and access is restricted, and the computer hardware is fault tolerant for minimal downtime. The better enterprise-level services provide Service Level Agreements that guarantee access availability.
