Coping with small backup windows
A generic tutorial from THEJRC

The Problem:

Increased need for runtime, increasing network load, and reduced budgeting are quickly narrowing the windows in which an administrator or recovery technician has to snap backups. Many shops have solved this problem by adding Storage area networks to their architecture, however the costs involved are high and as budgets are decimated by market changes mid to large companies cannot always afford such a move. Even more depressing is the smaller companies who could not afford such a move at all on smaller budgets.

The solution factors:

Tape backup is reliable and predictable as it has been around long enough to be considered grown up. Almost all networks handling data are using tape backup devices such as DAT, DLT, and AIT drives (and libraries) for their backup systems.

The latest fad in backups has been backup to disk, where a large IDE or SCSI disk drive is used in replacement for the tape drive and the backup run to that. Disk backups are much faster as the architecture has become more advanced in recent years, however the failure rate with large disks has still presented a problem. Storage Area Networks (SAN) typically works on both disk and tape backups with the primary snapshot being taken to disk as it is fast enough to backup within a more narrow window, and the disk backup being moved to tape when finished. This is the solution we are going to focus on, only with a more budget minded approach.

Network attached storage is another newer architecture we will be working with, a NAS appliance is typically a standalone unit with several disk drives running raid to create a large storage environment. These devices typically use a network based interface for administration and they are typically managed through a browser from a desktop. NAS appliances offer four things we are looking for: low cost, large storage capability, fast I/O speeds for transfer of data, as well as easy management. You can pick up a NAS appliance such as the Cobalt NasRaq, Maxtors MaxAttach, or Dells Powervault for as low as $600.00.

The deal:

Well, its pretty simple from here, backup to the NAS appliance when your window comes up, and when it is complete backup the NAS appliance to tape!! This is the same theory of backup operation used in your higher end and much more expensive SAN environments, only scaled down to a simpler budget. The backup to the NAS appliance can typically be done through FTP, Web based upload, or your windows network neighborhood (if you are running windows servers) and there are a variety of software solutions out there to help with scheduled backups to a network device. The tape backup can often be connected directly to the NAS appliance (with most systems) or run from a system on an isolated subnet attached to the second network port of the appliance (most appliances have two ports) thus reducing network traffic caused by the tape backup.

So there it is, a simple solution for a growing problem in the small to mid sized IT environment. There is nothing super fancy about it, and the solution isnít driven by a 400k a year IT consultant. The flexibility of the NAS unit allows for many other tricks when migrating data, as well as a good backup file server when in need. For less than 2 grand an IT shop can add a lot of data redundancy, and a good tool for disaster recovery with very little effort. If you want more information, or would like examples of these systems that I have set up for clients pm me... eh