Best way to use 4 disks?

[Neil Whitworth]

I have been playing with FreeNAS (8.3.1) for a couple of months now - just seeing what I can/can not do with it. I treated myself one of these Supermicro 5017C-MTF ( X9SCL-F/E3-1220 V2 @ 3.10GHz/16 GB ECC RAM). I also bought 3 x Seagate ST4000VN000 4TB NAS drives which I have been running RaidZ - Yes, I know RaidZ is not ideal, but funds were limited and this was just to try things out before throwing everything away and starting again...

My plan is to use this system for storing (in order of importance):-

• Primary storage of Digital Photos. currently around 200Gb but growing steadily
• Backups of other computers. Probaly around 0.5Tb - 1 Tb
• Media rips (CD/DVD). Annoying if lost but not critical. Probably around 2Tb+

I am going to buy another Seagate ST4000VN000 4TB NAS drive which will then fill this case. My question is how to best make use of them?

1) 1 pool with All 4 drives in RaidZ2.
Pros: Simple to understand, should survive failure of 2 hdds.
Cons: Only stores photos in a single location - if the worst happens and the pool is lost everything is gone.

2) 2 pools - 3 drives in RaidZ + 2nd pool of a single drive. On RaidZ vol create datasets for Photos/Backups/Media and then setup zfs replication for 'photos' to 2nd pool on single hdd.
Pros: photos on multiple pools- I can loose either pool and not loose data.
Cons: more complicated.

Is option 2) a good idea or just plain stupid?

 

[cyberjock]

I think with option 2 you are also ignoring the fact that if you loose a drive with the RAIDZ you are probably looking at a complete pool rebuild since you can expect to have some kind of corruption(statistically speaking).

I understand your need to compare 2 different 4-drive configurations, but they really are apples-to-oranges in the simplistic way you are describing.

What I'd do is build the RAIDZ2 and then get another disk to backup the most important data.

 

[Neil Whitworth]

I think with option 2 you are also ignoring the fact that if you loose a drive with the RAIDZ you are probably looking at a complete pool rebuild since you can expect to have some kind of corruption(statistically speaking).

I think I could live with the posibility of loosing the pool - as long as I knew the important data was somewhere else

I understand your need to compare 2 different 4-drive configurations, but they really are apples-to-oranges in the simplistic way you are describing.

What I'd do is build the RAIDZ2 and then get another disk to backup the most important data.

I would like to have RaidZ2, and am leaning towards that option. But because this case can only have 4 hdds I would be left with trying to find some way of connecting more drives - USB? eSATA?