recommandations or "am i right?"

[snaptec]

Hello to all,
I'm thinking to switch to freenas. Already tried with some old stuff and it already works quite good.

What I want:
Expandable, safe storage, that is not the slowest under my control. sure I have a extra backup

For what I need it:
2 things:
a) owncloud data space
b) backup space

both used over the internet, connected through 500mbit up/down.

What i already have
Supermicro sc836 chassis with redundant PSUs
(not for freenas, but the owncloud server)
X10slm-f, 32gb ram, e3-1231v3, 2x 1TB ssds mirrored for os & database

What I would like to buy for the freenas system:
x10slm-f
g3260
16gb ECC ram
2x m1015 connected to the backplane with 4 sf8087 cables
installed in the sc836 chassis

I have 16 slots, which configuration schould I choose(regarding performance)?
3 striped 5x4TB raidz2
2 striped 8x4TB raidz2

I want to begin with one raidz2 and expand later.

Also maybe later expand the ram to 32GB and upgrade the CPU if needed. Connections only through NFS, maybe iscsi.

What ist the best way, regarding price, expandability and performance I should go?

At the moment the data is stored on a raid6, but I'm not happy with that. 4TB in use at the moment.


thanks in advance

 

[solarisguy]

Please tell us more about your needs and/or vision for expandability. That is an area where I can often see some misunderstanding of either FreeNAS or ZFS or storage complexities in general.

Thank you.

 

[snaptec]

My wishes are reliable, good priced storage.
At the Moment 4tb for around 50 owncloud user. More to come. Plus Backup storage.

The owncloud machine is dedicated, just the data will be on freenas.

The maximum space would be 2 vdevs containing 8drive raidz2, or 3vdevs with 5 Drive raidz2(what Performs better)
If I need more I think a second machine is a good choice.
Another hba card and an external enclosure is not the right way with only 32gb RAM I think!?

 

[solarisguy]

You did not write too much about expandability :D

You are right, 32 GB of RAM for 64 TB of disks does not allow for significant storage growth.

2 striped 8x4TB raidz2 is a much better option than the other one (in a 5 disk RAID-Z2 only 3 disks out of 5 have data).

If your usage pattern allows that, I would like to suggest that you would consider deploying
8x 6TB RAID-Z2
and then after sometime deploying
8x 8TB RAID-Z2
However, that is a viable option only when you can have two independent storage volumes. And 32 GB of RAM might be instantly too tight with many simultaneous users (a better motherboard would be required upfront). Nevertheless, rolling out your storage incrementally allows you to significantly delay a deployment of the second server.

 

[snaptec]

Thanks. If I want to expand more, I will buy another machine as the 32gb ram wont be enough.


Yes it is possible to have 2 sets.
After reading through the forums how Bad is it that a size of 8 is not recommended?
Best practise would be 6 or 10 disks with z2. I know there will be a couple tb missing, thats ok. What interests me is the Performance impact. Another way would be to use 6 sized arrays and Mount the Last two disks internal. Any nogos about that?

I testet the Last month with a crappy Athlon x2 430, 8 gb non ecc RAM, and 6 disks without a Problem and good Performance. Am I thinking too much?

 

[solarisguy]

In real life, any RAID-Z2 with more than 6 disks is OK
http://blog.delphix.com/matt/2014/06/06/zfs-stripe-width/

P.S.
Matthew Ahrens is one of guys behind ZFS https://en.wikipedia.org/wiki/OpenZFS