Many years ago, I finally got sick of failing disks and the panic that follows them, so I decided to buy a NAS (Network Attached Storage). A fair amount of research suggested that ReadyNAS devices were cost-effective, flexible and reliable. So, I bought an NV+. Although its a little eccentric to configure (done via a web interface), it was straight-forward enough, and I could even install my own sofware on it, as it runs Linux. This was useful: I run Bacula to do my backups and I could install it directly on the NAS.
Of course, the whole point of using a NAS is that the disks are replicated, so I should never have to deal with a failed disk again - just swap in a new one and the data will be recovered from the other disk(s). What's more, the ReadyNAS will even allow you to expand your storage by adding bigger disks as time goes by. What could possibly go wrong?
About a week ago, after many years of reliable service, I found out: the power supply. One morning, my ReadyNAS was dead, never to live again. No problem, just replace the power supply, you say. No such luck: the version I use went out of production long ago and power supplies are about as available as hens' teeth. OK, so buy a new ReadyNAS? Haha - the joke is on me: NV+ v1 disks don't work in NV+ v2, and they don't even make the v2 any more, though it is still possible to find them around (unlike the v1).
So, what's the one true answer? Luckily there is one: commodity hardware. I set up a new system using an HP Microserver, FreeBSD and ZFS. Cheaper, does everything a ReadyNAS can do, and now even power supplies can't catch me out - if it ever dies, I just buy a new box and plug the disks in. It doesn't have to be HP, so long as it has a 64 bit Intel compatible CPU and SATA disks, it'll work just fine. In my defence, this wasn't possible when I bought the ReadyNAS, and it does require some sysadmin skillz, but this time I have a truly bulletproof solution. And thanks to Bacula, the contents of my dead ReadyNAS are easily recovered.
Netgear ReadyNAS NV+ [Amazon UK]
HP ProLiant MicroServer [Amazon UK]
Netgear ReadyNAS NV+ [Amazon US]
HP ProLiant MicroServer [Amazon US]