Some time ago I wrote about the new network storage device I had installed in order to secure the data entrusted to it for our household computers. The Synology DS409slim DiskStation is a network attached storage server which replaces the data backup and storage functionality for which I had previously used for around five years a Buffalo Technology LinkStation 250GB. Not that I had become dissatisfied with the LinkStation; I still use it but only as a media server for our photos, music and videos, which are also backed up to the DiskStation, and it hadn't run out of space.
The reason I wanted a replacement was that the LinkStation was a single point of failure: it's 250GB of storage is all on a single disk; backing it up required it to be regularly copied to a removable hard drive, over the network, which at 100mbs/sec took an eternity; it is quite noisy: when the disk is accessed and spins up to its full speed, you can hear it humming, even though the device is sat on noise-reducing material.
The DiskStation eliminates most of these problems: it has four hard drives, configured as RAID 5, with three drives active and one spare, to be swapped in to replace any other drive that has failed. Consequently it doesn't really need to be backed up at all simply for the purposes of ensuring that data isn't lost due to drive failure although that doesn't eliminate the desirability of backing up the data for other reasons, such as protection against loss in the event of, for instance, a house fire.
So, what disks to use? Well, due to the compact design I was limited to 2½" drives mostly used in laptops, rather than the cheaper 3½" drives that are used in desktops. From what I had read on the Web, Hitachi disks always seemed to get a good write-up for performance and reliability so I would be looking at the TravelStar range. I also wanted the faster 7,200rpm drives as these also come with a larger internal cache (16MB as opposed to 8MB for the slower drives) and so capitalise on the gigabit network interface to provide fast data transfer speeds.
I got a good deal from Oyyy at less than £40 a drive, including VAT and delivery. I chose the 250GB drive capacity as, even configured as RAID 5, it would give me around 700GB of storage, bearing in mind that I hadn't come anywhere near filling the original 250GB of the LinkStation. The Disk Station would essentially only be used for data backup, the LinkStation being retained simply as a media server, for which a 100mbs network interface should be more than adequate.
Installing the TravelStars was simple: each screws onto its own caddy, each of which slots into the back of the Diskstation, interfacing via the SATA II slots on each drive. The four drives took about an hour to format and configure.
The DiskStation has now been in use for about six months and has performed faultlessly. The Hitachi TravelStar disks are noticeably quieter than the disk in the LinkStation: you simply cannot hear them spin up as they are accessed like you can the LinkStation.
The Resource Manager in the Synology Admin Manager indicates that in operation the active disks run at around 31C whilst the inactive spare is at around 38C, all within acceptable operating parameters. Data transfer is lightning fast, so proving that striping data across three disks, even with the error recovery built into the RAID 5 format, makes good use of the gigabit network speeds that the Synology DiskStation provides.
Of course, only time will tell but, so far, I have absolutely no doubts that the Hitachi TravelStar drives were the right choice for this platform.