Storage/RAID help

[wrkngclasshero]

So my library is becoming a bit too large for conventional external hard drives (over 2TB and growing daily).

Currently I have a 1TB iMac and a 2TB WD external HD. All of this is backed up via Time Machine on a 3TB Seagate External HD.

What I would like is some sort of enclosure that can house 4 drives and would allow two separate raids. I am hoping to combine 2x 3TB drives with Raid 0, and combine two other drives( 1x 2TB & 1x3TB) with a Raid 0.

Then I would like to use the 6TB raid as my time machine drive to back up both the 5TB raid (which will house my iTunes library) and my 1TB iMac.

I have looked into the Drobo but am a little leery and think I would rather a more traditional RAID.

One last thing, I was hoping for either FW800 or Ethernet connectivity.

Quite the laundry list I know so, thanks in advance for the help!!!

 

[firestarter]

Backing up onto a RAID 0 makes little sense. If you want a backup, then something more resilient than RAID 0 would be better.

It's interesting to plan backups by looking at how your data changes over time. Unlike regular files, iTunes managed files are rarely altered or deleted - they're just added to over time. You want to spec RAID0 so that you have a large amount of contiguous space to run TimeMachine - but I don't think TimeMachine is necessarily what you need for an iTunes library. Instead, I'd suggest chronosync - you can use this to split your backups over two non-RAID0 disks and essentially it will run hourly backing new files up as TimeMachine would have.

You also don't really need RAID0 and contiguous space for your primary drives. MY iTunes library was pretty well established - but recently I upgraded my main library drive and got iTunes to copy over. iTunes 10 now separates media types into 11 or more directories. I would keep the main library on one drive, and symlink the largest directory (say Movies) over to the other. That way you can maintain a pretty balanced usage over two disks without taking the reliability hit that RAID0 would bring.

By not using RAID 0 and TimeMachine, this sort of setup would allow you to swap your two backup drives occasionally with offsite versions. Those two (four) backup drives would be easily readable - no RAID set complications or TimeMachine links - just a regular file system.

 

[wrkngclasshero]

Firestarter, you raise a lot of good points. A couple of follow up Q's if you don't mind.

1. With all of these back ups happening between drives, do you think playback performance would take a hit?

2. Would you have an enclosure recommendation?

3. Would you have a drive recommendation?

4. The symlink is interesting, would it be possible to split the movie folder between 2 drives (I suspect not but no stupid questions right...)?

5. Any thoughts on MediaSonic bays? They have reasonably good reviews and at stellar prices.



Thanks a ton!!!

 

[firestarter]

Firestarter, you raise a lot of good points. A couple of follow up Q's if you don't mind.

1. With all of these back ups happening between drives, do you think playback performance would take a hit?

Probably not. Most disk interfaces are a lot faster than the bandwidth required to play back movies. If it was a problem, you could sync backups to run unattended at some quiet time of the day.

Something like Chronosync only backs up changed/new files. How much data is that on a typical day? Probably not much.

2. Would you have an enclosure recommendation?

I don't really. When I started needing more disk space I bought a MacPro just for the 4 drive bays. I also have an external two bay caddy-less enclosure I use for backups which is made by WiebeTech and a lot of single drive enclosures (IcyBox). WiebeTech are good, but not very good value for money - quite expensive.

The problem with cheaper bays is small noisy power supply fans - worth looking out for.

3. Would you have a drive recommendation?

The Western Digital green drives switch down to a lower speed to save power and produce less heat/noise. They're well priced and plenty fast - seem quite good.

4. The symlink is interesting, would it be possible to split the movie folder between 2 drives (I suspect not but no stupid questions right...)?

Not easily, unfortunately.

I've got a fair sized library (800G) - but I've kept the size down by not putting my movies into iTunes. I use other readers (like GoodReader) to hold movies for viewing on my iPad - just to avoid adding to my library.

I've also experimented with archiving Apple's iTMS protected TV programs to another disk and deleting from iTunes. This works - you can still play them off disk and also add them back to the library - and they continue to work, despite being protected. Worth a thought - do you really need all that stuff in the library?

Thanks a ton!!!

No problem. It's a problem I'm dealing with myself. At the moment I usually do manual backups of my library every week or two, since I figure it doesn't change very rapidly, and I have most of the original media.

Remember also to include your iTunes library database files (from your home 'Music' directory) in your backup.