An important consideration for any organization is protecting their company data through backup; for small companies this is essential. Small businesses often purchase a server computer with only a single hard disk, providing little or no protection against data loss due to system or hardware failure.
Without a current backup, even companies that employ a mirrored hard drive configuration may only realize limited recoverability.
To help protect against data loss, companies running Microsoft Small Business Server 2000-based networks should plan for and implement regular system and data backups. This plan includes the purchase of a dedicated backup device and media, an appropriate backup schedule, periodic test restores to verify backup integrity, and off-site storage of current or recent full system backups. A backup plan should also include an associated plan for how to restore the data.
To deal with system failure and reduce the potential for problems, system recovery planning for Small Business Server is recommended.
Part one of this technical article should provide a discussion on backing up a Small Business Server computer. In addition, a description of common data restore and system recovery scenarios and best practice recommendations are included to help you better plan, monitor, and execute your backup-related activities.
Although the Backup Utility supports several types of backups, the three most common types of backup are explained and compared as follows:
Normal Also called a full backup. A normal backup copies all selected files and marks each as backed up. With normal backups, you need only the most recent copy of the backup file to restore all the files.
Incremental An incremental backup copies only those files that were created or changed since the last normal or incremental backup and marks files as backed up. If you implement a combination of normal and incremental backups, you must have the most recent normal backup set, as well as all the incremental backup sets, to restore your data.
Differential A differential backup copies files that were created or changed since the last normal or incremental backup, but does not mark files as backed up. If you implement a combination of normal and differential backups, you must have the last normal and last differential backup sets to restore your data.
Windows 2000 can back up files to a variety of storage devices, including a tape drive, logical drive, physical drive, removable disk, network share, or a library of disks or tapes organized into a media pool and controlled by a robotic changer. If you do not have a separate storage device, you can back up to another hard disk. It is not recommended that you use a logical drive from the same physical disk to back up your data. In case of a hardware failure, the data on the logical drive may not be available.
Storage technology changes rapidly, so it is important to research the merits of various media before you make a purchase. When selecting a storage device, consider drive and media costs, as well as reliability and capacity.
The most common type of storage medium is magnetic tape. The primary tape drives used for backup: include quarter-inch cartridges (QIC), digital audio tapes (DAT), 8-millimeter (mm) cassettes, and digital linear tapes (DLT). High-capacity, high-performance tape drives typically use small computer system interface (SCSI) controllers. Other types of media include hard disks, magnetic disks, and network drives.
In Windows 2000 Server, the Backup Utility does not support backing up to CD-R, CD-RW, or DVD-R because Remote Storage Management does not recognize these devices as backup pool media. If you need to back up your data to a device that uses one of the media types above, you will need to purchase third-party backup software that supports the specific media type of interest.
There are many aspects that you should consider before deciding which media type you will use.
An ideal storage device has more than enough capacity to back up the entire Small Business Server computer and can also detect and correct errors during backup and restore operations. It is important to plan for the future and growing demands of user data.
Price per Media Unit
Consider the price per media unit. Your budget may require you to make a trade-off between media type and backup schedule when purchasing the necessary number of media units. For example, if you are using a tape backup method, you should consider how many tapes you need to implement your backup plan for one year and then purchase as many tapes as possible up front. You should also consider purchasing spare tapes and plan for replacing worn tapes per the manufacturer’s recommendation.
The most common options are SCSI II, SCSI III, ultra-wide SCSI, IDE, USB, and IEEE 1394 (also know as FireWire). The bus may be built into the motherboard or it may require an additional expansion card. If you require an additional adapter, verify that the adapter is also on the HCL and that it is certified to work with your backup device.
Consider the bus and media speed. Depending on the amount of data you need to back up, you may need a faster device.
For a small company implementing a tape backup solution, how often you store tapes off-site depends on how critical the data is. Some companies may elect to take backup tapes home every day; for others, weekly or monthly off-site storage is sufficient.
A small company will typically designate one employee to swap backup tapes in the backup device and store tapes off-site. It is important to clearly and consistently label your backup media. Consider posting the backup schedule and procedures near the backup device for quick reference.
Plans vary based on your company’s need, resources, budget, and other factors. Ultimately, a backup plan should be based on how often your data changes, how valuable it is, and how much you can afford to lose. Because most companies cannot afford to lose several days worth of data, a daily backup plan is recommended. When you develop a backup plan, how many tapes you use, what types of backups you perform, and when tapes are stored off-site are all variables that only you can define. Once your plan is in place, it should be regularly evaluated for effectiveness and modified as necessary.
Part two of this technical article will focus on designing a backup plan.