Tuesday 30 April 2013

Ripping your CD Collection - V. Storage

My own collection, which includes a healthy mix of CDs and downloaded high resolution audio files is now approaching the 30,000 files mark.  This occupies 1.2TB of disk space for the FLAC master library and 1.4TB for a replicated Apple Lossless library.  I am totally paranoid over the consequence of losing all of this to a HD failure.  I have endured several HD failures in my lifetime, so I know that they happen more often than you would like, and generally without warning.  I don’t want to imagine how much time it would take me to re-rip my CD collection, and re-download all my downloaded music.  I don’t know if that would even be possible!

There are various ways to address this issue.  First, is the obvious one, back it up!  I must confess I don’t like backup utilities much.  They seem to be overly complicated, designed as they are to deal with the myriad complexities of the gamut of computerized data.  I always suspect that when I need to use it, I won’t be able to work it!  Another option is to keep a nice simple copy of everything on another HD somewhere.  The problem is that you get lazy, and you don’t back up as often as you should.  But in general, backing up and copying strategies can be quite successful.

The solution I favour is to put everything on a Networked Attached Storage (NAS) unit.  A NAS is a very powerful device, but can also be very expensive.  There are cheap units at the $200 price point, and expensive units at the $1,000+ price point.  And that’s without any HDs!  The cheap units are more than likely going to be less reliable, and that completely misses the point of using a NAS for storing your audio data.  The most expensive units have a higher level of performance (read/write speeds, ability to connect simultaneously with multiple users with little performance loss, etc) and are aimed mainly at corporate applications.  As usual, the best deal is to be found somewhere in the middle.  I bought a Synology DS411j unit a couple of years ago and it has worked flawlessly for me.  Tim has a similar one.

After you buy your NAS, you have to kit it out with multiple Hard Drives.  Mine takes four 3.5” hard disks.  These disks are then formatted into what is known as a RAID array.  RAID is a scheme whereby the data is distributed across the multiple disks in such a way that if one disc should suddenly fail, then none of your data is lost.  You just replace the failed disk, rebuild the RAID, and you are back again at full operation.  Some NAS units will let you do that without even having to power it down (so-called “hot-swapping”).  There are different “Levels” of RAID, and they all have different characteristics.  Some will even allow more than one disk to fail with no loss of data.  When I started out, I built my NAS with four 500GB HDs, but soon learned my lesson and swapped them out for four 2TB HDs.  Configured in “Synology Hybrid RAID” this gives me 5.8TB of storage, and I can survive the failure of any one HD without losing any data.  As well as my music, I can store a whole load of other mission-critical data on there too.  My NAS is also plugged into a UPS so that if the power fails it can shut itself down gracefully.  The whole shebang sits in a room in the basement, next to the network router, well out of harm’s way.

My paranoia leads me to also be very picky about which model of HD I put in my NAS.  Ordinary consumer grade HDs fail – in my experience – at a rate higher than I feel comfortable exposing myself to.  Therefore I only buy “Enterprise Class” HDs.  These have a much lower failure rate, but, as you might expect, cost a good 50% more.  My own HD of choice has been the Western Digital RE4 family, and I own several of these without having incurred a single failure.  At one time they were in short supply and I had to buy a pair of Seagate Constellation ES 2TB units.  One of these subsequently failed – actually, the Synology warned me of its impending failure before it actually died, and Seagate were happy to replace it under warranty based on the warning alone – and the replacement unit has so far functioned without further incident.

I can attach an external USB drive to my NAS, so I have plugged in a spare 1.5TB external LG unit.  I place a further double-paranoid copy of my FLAC library on there for safe keeping, just in case...

If you are keeping tally, that’s about $1,200-$1,500 spent on my file storage system.  6TB of cheap storage capacity will set you back about $600, so that’s an awful lot extra to budget for little more than data security. You may feel differently from me as to whether it is worth it.  But so long as you have taken the time to pause and think it through, then that’s good enough for me.

Back to Part IV.
Part VI can be found here.