Drive configuration assistance...

[MDKRUSH]

Okay so I looked at the PPT from Cyberjock (thanks!) and now I have a couple of questions...

So I have 4 750 gb 7200 rpm drives and 4 500 gb GREEN drives.

I was thinking that my best configuration would be 2 Vdev's of RAID-Z1
Vdev 1 - 3 750gb drives
Vdev 2 - 3 500gb GREEN drives

One Zpool.

So if I do this I should have roughly 2tb of usable space...?

1. Is this a good idea? Is there a better way to maximize space with a little redundancy on the side?
2. How will performance be affected with the 750gb drives being faster than the 500gb drives?

My current setup is 4 750's in RAID-Z1

Thanks!!

 

[MDKRUSH]

Okay, so I ordered ASRock C2750D4I yesterday and a couple other things...
My additional question is:

3. Same setup could I use 2 Zpool's instead?

 

[cyberjock]

Your setup would have 2TB total.

RAIDZ1 isn't recommended(read my sig link and decide for yourself)

I think the current concensus is that the ASrock c2750d4i isn't a good choice for FreeNAS. I think (and I could be wrong.. please do your homework) is that it doesn't even boot up yet with FreeNAS without crashing. The Avoton hardware(more than likely the chipset) isn't supported, and has serious compatibility problems.

 

[indy]

RAIDZ1 isn't recommended(read my sig link and decide for yourself)

The article assumes the rebuild will come to a halt when encountering a URE.
From what I read, ZFS will try continue the rebuild, which should be very likely imo.

However I would be worried about an additional disk failing under the stress of rebuilding.

 

[cyberjock]

The article assumes the rebuild will come to a halt when encountering a URE.
From what I read, ZFS will try continue the rebuild, which should be very likely imo.

However I would be worried about an additional disk failing under the stress of rebuilding.

This is one difference between ZFS and hardware RAID. With hardware RAID it will sometimes stop completely, others will continue but you will be left with the condition of your RAID. The file system may be damaged beyond the usability of the RAID>

ZFS will always continue but it will take whatever corruption it receives and process it as best as it can. For some people this means a file or two will be lost, for others the zpool will immediately be trashed and be unrecoverable without serious twiddling with the data on the disks. ZFS assumes there is never a condition where corruption isn't correctable without parity data. With RAIDZ1, if you are recovering a disk you have no parity at all during the process, so you are walking along the cliff-line the whole time. You might fall off or you might not. But, plenty of people have been thrown off the cliff. It's your risk. Take it or leave it. People seem to not realize how dangerous UREs are. And the weekly user that loses a RAIDZ1 pool has motivated me to put that link in my sig.