Tip of the Trade: SATA Storage Servers
I like SATA hard drives. I like them a whole lot. While SCSI drives are still the toughest and most reliable, SATA drives have many advantages. They don't need expensive controllers. They use nice skinny cables that come in many pleasing colors; they can be hot-swapped; and you get a whale of a lot of gigabytes for your buck. Here is a quick cost comparison from a random shopping site: SCSI drives may be the toughest and most reliable, but oftentimes SATA drives are equally good. From price point to form factor and feature options, they offer a plethora of advantages.
- Seagate Cheetah 10K.7, 146GB Hard Drive Ultra320 SCSI $266.99
- Seagate Barracuda ES.2, hard drive, 1TB, SATA-300 $311.99
The SATA drive is the runaway value winner here. When you need SCSI, there are no shortcuts, but when you're not running high-demand mission-critical 24x7x365 servers, SATA drives make sense. When you need to build big storage arrays, SATA offers many options.
The first option is one of my favorites, a Linux-powered SATA RAID storage server built on PC hardware. You can stuff as many as eight drives into a single box. (Don't forget to have adequate power and cooling.) Linux software RAID coupled with Linux Volume Manager (LVM) is a great performer, reliable and very flexible.
When you need large storage arrays or want to use external drives, however, PC hardware can go only so far. Then, you want to investigate the wide world of external SATA enclosures. These come in all sizes, with all kinds of great features. You can start small, with single-disk enclosures like the Rosewill RX-358-S SATA/eSATA enclosure, which ranges from around $20 to $50. The Rosewill includes a cooling fan, supports SATA I and II, and connects via either USB or eSATA. eSATA is a new external interface just for SATA that promises faster-than-Firewire speeds.
I prefer a stand-alone enclosure over an external hard drive because then I can use any hard drive I want. I don't need the bundled software that comes with stand-alone external hard drives; Linux sees the drive as just another ordinary block device and already has all the utilities and applications that I need.
An interesting wrinkle is the 3-in-2 SATA modules that stuff three SATA drives into two external 5.25" drive bays. These typically include independent power switches, hot-swap trays, status LEDs and overheating alarms. There are also 5-in-3 models, like the RAIDAGE jAge35R40. Prices vary a lot, starting from around a hundred dollars.
Then there are the mondo biggo external enclosures, like the SATA Beast. This is a 4U rackmount enclosure that holds 42 drives. That's right, count 'em, 42. Everything is hot-swappable and redundant. It is OS-independent and has a Web administration panel.
So the moral of the story is, when it comes to hard disk-based storage, a wealth of good options are available.