My first dedicated storage drive for pictures was an 160GB 3.5” disk sporting a clunky USB enclosure. At the time, 160GB seemed an immense amount of space.
After eating that 160GB drive, my images quickly went on to consume numerous larger disks. 320GB, 500GB, 640GB, 1TB, 1.5TB, 2TB…
It didn’t take long to discover that bare hard drives cost less than disks in external enclosures (at least in Asia); those bare disks are also easy to switch in and out of USB-SATA docks as needed. My next storage revelation was that backups would be far easier to manage if I were to buy drives in identically sized pairs. I then read about off-site backups and once again headed to the computer market for another USB dock, and yet more hard drives.
After a few years of sorting through an ever-growing stack of storage drives and syncing backup disks, that system became cumbersome. Files needed for delivery or stock requests were too frequently on an earlier drive. Projects that spanned multiple disks (which I arranged by date) were more difficult to find than they should have been. I wanted to store all my work in a central repository; one really big hard drive for everything. The problem was that I was already using the largest disks available.
After a bit of research, it was clear: I needed a NAS device (NAS=Network Attached Storage). Here’s why:
- RAID - Nearly all NAS systems are based around the idea of creating one big disk out of multiple smaller disks (usually via a RAID arrangement where one or more disks in the array are used as a redundant fail safe of sorts)
- Connectivity - Most NAS boxes connect via gigabit network cables (or better), which can be faster than the USB2 I was using at the time
- Interoperability - NAS systems use universal file transfer protocols, which make drive format irrelevant. I use a combination of OSX, Windows and Linux systems to access files, which can otherwise cause drive format headaches (Macs don't particularly like NTFS; Windows can't read HFS+ and Linux can't write it; Windows and Mac systems don't have any idea what to do with ext4 or other common Linux file systems.
There are numerous commercial NAS devices on the market that come in an array of shapes, sizes and price-points. I chose to avoid them all and instead build a file server using the FreeNAS operating system for the following reasons:
- Cost - while the price of small, low-end NAS appliances is only slightly more than the cost of building a relatively nice FreeNAS system, that cost discrepancy balloons rapidly with devices supporting 10 or more drives.
- Scalability - the drive capacity of a FreeNAS system can be expanded at relatively low cost and without a set upper limit. Commercial NAS appliances generally can't be expanded beyond the number of drive bays present when manufactured; to add disks beyond existing bays, you have to buy a new NAS.
- Parts availability - a small to mid-size FreeNAS system can be based entirely on consumer parts available at any computer shop. If a part breaks, it's easy to buy a replacement. Most commercial NAS appliances use a jumble of unusual parts available only from the company that makes the NAS. If the power supply goes up in smoke, be prepared to wait to have a new one shipped from the manufacturer. I worked at a studio where the company NAS appliance burnt out two power supplies in the space of a couple months.
- Data security - FreeNAS supports the ZFS filesystem, which is the only filesystem designed for securely archiving data. It actively checks for bit-rot and corrects errors that may be found. Almost all commercial NAS appliances use different filesystems that are less advanced and don't care if your pictures get corrupted or go missing. ZFS also has built-in backup and data revisioning capabilities.
- Compatibility - FreeNAS runs on a wide array of hardware. I can take the disks out of my NAS and move them to completely different hardware without issue. Doing the same is not possible with many commercial NAS boxes running proprietary software. DROBO is one such unit which is heavily marked to photographers; if a DROBO dies, the disks from that machine are only readable in another DROBO (if you are lucky).
- Support and documentation - as an open source project, FreeNAS has better online documentation and community support than many commercial devices. I like to be able to solve problems on my own; if you don't, it's possible to buy commercial FreeNAS support and hardware.
- Flexibility - the software on most commercial NAS devices is relatively limited in scope; if you want your NAS to be more than a simple file server, you may be out of luck. FreeNAS has built-in or ad-on support for a wide variety of services that go far beyond simply storing pictures.
I have a number of pages on this website with details about my experiences using FreeNAS; other people have done a better job describing the basic principles involved though. Here are a few things can help better understand archival digital storage and FreeNAS:
- Bitrot and atomic COWs: Inside “next-gen” filesystems This page has a solid explanation for why regular RAID arrays offer less data security than might be expected.
- FreeNAS Website It should come as no surprise that the FreeNAS website contains a wealth of knowledge about the operating system. The documentation pages are extensive; any unanswered questions can usually be solved by searching the forums.
- IXsystems IXsystems is the corporate sponsor of FreeNAS. I happen to enjoy building my own computer systems; if you aren't of that persuasion, purchasing a ready-made FreeNAS system might be a good idea. The FreeNAS Mini appears to be a high-quality, well-priced option for a small NAS box.
Here are a few things on this website that may be useful:
- Approximate comparative guide to NAS cost. I should improve this chart and publish it as a regular webpage but haven't. If you don't run software with .ods document support, I feel for you. The chart mostly uses my current hardware picks for the FreeNAS side and a few recent consumer NAS devices as comparison. FreeNAS can run on far less expensive hardware, but the relatively expensive hardware I like to run is still lower cost than the prefab systems (which are less powerful and have far less substantial data security features).
- FreeNAS Compatible Hardware List I don't necessarily recommend much of the hardware listed but have used it all successfully. The first entry is for my current primary system, which is quite nice.
- Details about flashing the LSI 9211-8i HBA for FreeNAS If you end up with a medium to large NAS, you will need to find a way to connect more hard drives than your motherboard might otherwise support. The LSI 9211-8i HBA is one of the better options for such expansion.