The company I work for utilizes an old, clunky Window SBS as a file server and Domain Controller. They're looking to reorganize their storage infrastructure to deal with data demands. I'm thinking a NAS would be the best solution but I haven't dealt with one before. Can a NAS be configured to not only serve files with RAID, but also store incremental backups of the data? If so, would there need to be multiple drivers in place (2 for raid and 1 for backup)?
3 Answers
The problem with the question is, there are some specifics you need to provide: budget, time constraints, amount of effort, number of users, power consumption, and even the amount of space you need to provide all factor into the equation.
Can a NAS be configured to not only serve files with RAID, but also store incremental backups of the data?
It depends on the device/software.
If you are looking for off-the-shelf, there are several devices, each with different features. You're better off developing a very specific list of requirements and going forward selecting a box that suits your needs. Keep in mind, using vendor-specific hardware will almost always require the same type/model of hardware in a recovery situation.
If you are looking for a mix of off-the-shelf, and do-some-of-it-yourself, get an HP Microserver, and run FreeNAS on it. FreeNAS has timed snapshots, and supports time-scheduled over-the-network syncronization with another FreeNAS device, making it possible to keep a hot-spare server around that can be brought online with little data loss in a very big hurry. There are other software packages that will work as well, including OpenFiler, NexentaStor, and of course, some variant of Windows Server. Whatever filesystem you choose, pick one that you can easily get to (NTFS, or Ext3 usually come to mind). The exception here is (of course) ZFS, which requires a ZFS-capable OS to read. Fortunately, that's not too hard to get, given that FreeNAS itself supports ZFS, and can be run off of a USB stick.
If you are looking to do the entire thing yourself, hand-pick decent-quality parts to make your own NAS box, and run ${insert preferred version of software from prior paragraph here} on it. Be sure to pick a processor/board combo that has enough umpf to keep up with your users, but don't pick something so big (and power hungry) that it's not worth the money. Put the remaining money into RAM, lots and lots of RAM. Pick a power supply, and oversize it by 100 watts or more. The reason? Power supplies degrade slowly over time, reducing their effectiveness to produce peak power as they age. Because a computer only draws the power it needs, having a slightly-larger power supply won't result in increased power consumption, and a high-efficiency power supply will also help with minimizing use. By having a slightly over-sized unit, you are building in additional years of service.
If so, would there need to be multiple drivers in place (2 for raid and 1 for backup)?
This is probably the most common case. Two drives (mirrored) and a single backup drive (usually in an external USB enclosure) can be made to work, but only if you keep a spare drive for your mirror that isn't plugged in, and only if you keep your external (3rd) backup drive in a format that can be easily plugged into any computer in a hurry.
You will want to enable SMART monitoring on all of the drives, and perform checks on them at least weekly. If possible, set the AAM feature on your drive(s) to the lowest setting, which in turn will help slightly with their lifespan. Most modern drives are fast enough and have large enough cache that slowing down their seek movements with AAM won't have much, if any, impact on overall performance.
It certainly can be done, but I would never, ever do this. If the NAS dies, both your data and your backup are gone.
You don't want to use a pre-made NAS device. Most of those devices have their bandwidth throttled down through a USB2 controller and sometimes you can only get 3-10MB/s ., much slower than most USB thumbdrives. I would be very careful about what you buy. Plus, some of them will go to sleep , and in a work environment you dont want your NAS to be doing that.
I would do as Avery Payne suggests, and run a distro of FreeNAS on a HP Miniserver. Basically , what you want is a device that has a hard drive on a SATA controller and a Gigabit ethernet port if possible, with mature power management.