known issues with different HD´s (Manufacturer / Model / Version) ???

[john carmack]

Hey guys :)

i am new here and i must say this is an pretty cool community :)

And now i have a question.

I am about to build a NAS Server with Raid(Z) 5.

I have 8 x 500GB Hard disks from different manufacturers with different versions, models and different Interfaces (Sata2 / Sata3...)

So - each HD is significantly different except the size!

Are there known issues using this kind of configuration?

Thank you! :)

 

[Stephens]

Strongly consider a RAID-Z2. Yes, you'll give up "1TB" (versus 500GB) to parity information, but it'll be much more reliable. Generally speaking, SATA2 vs SATA3 won't be an issue, and neither will mixing manufacturers and BIOS versions. Of course, if a given drive has bugs, all bets are off. The only way you should have a high degree of confidence (nothing is 100%) in its stability is to build it and test it. If you encounter any problems, I'd consider it the exception, not the rule.

 

[judyalex25@gmail.com]

I think Stephens answered the right solutions here. I wan also thinking the some about this manfuacturer Model Version.

 

[travalon]

I have 2 0f these http://www.newegg.com/Product/Product.aspx?Item=N82E16822148591 and though I don't see any problems, during boot there is a long list of warnings about kernel panics and such. Also (and I know this has been covered) there is 2 gb taken for swap and the standard 1000MB vs. 1024MB argument reducing drive capacity but my math still doesn't account for an additional 12 GB. So maybe the SSD part of the drive is not in use. IDK.

 

[titan_rw]

The nand flash on those hybrid drives doesn't add to your usable space. It simply speeds up reads for some data. For zfs, I wouldn't have even bothered. Extra system ram will give you much more benefit, as I'd wager zfs is more intelligent on what to cache as compared to the hd's themselves.

Also, besides the 1024 / 1000 numbering issue, keep in mind zfs reserves 1/64 of the total pool size for CoW. I think it's 1/64 anyway. If you have 2x 500gig in mirror, I'd expect about 435 gigs of formatted zfs capacity, as reported by 'df -h'. That's a guess based on previous experience with zfs pools.

 

[travalon]

@ titan_rw thanks for that. I'll be pulling them in case they're causing the permission issue caused here.
http://forums.freenas.org/showthrea...evice-192-168-***-xx-mnt-media-does-not-exist
I thought it was something I did but it turns out I didn't manage to change the permissions.