advice needed on new system, growth ability, hardware etc

[markm75]

I'm just beginning to look into some alternative solutions to buying more expensive dedicated NAS hardware like the Drobo 5N, to go along with 3, 4TB Seagate 5900 rpm sata III drives which in a traditional raid 5 or beyondraid config give me around 8TB of usable space for Windows mappings..

So I ran across info suggesting FreeNas as one option, or perhaps Linux based options.. i'm primarily a windows person, so this area is very foreign to me, though I've heard good things about FreeNas and ZFS file systems.

I came to realize though, that with ZFS there is no expansion option for adding another drive and increasing the size, like with Drobo or other solutions (are there any in linux in general)?

So hardware wise for this, this is what i've come up with so far.. i'm assuming a dual core 1.6 is better than 1.0 in most cases, in raid 6 especially..

8 ports on motherboard FM2 AMD A85X Hudson D4
With
AMD A4-5300 Trinity 3.4ghz socket FM2
For combined around $140

Now ram.. 8GB of Gskill for $52

Originally I considered a 1.0ghz or 1.6ghz combo board from newegg.. but i'd have to add a sata card to one of them eventually, bringing the cost closer to the above.
(amd e-350 1.6ghz)

I'll probably put all this in the rack size case i have handy, a supermicro sc825tq-560lp, which granted is only sata II, but shouldnt matter for gigabit ethernet and using sata III drives.


So all that said..

With freenas, no way to expand the array? What would the ZFS single parity equivalent to raid 5 be here? Does the freenas have a gui for managing remotely and sending alerts on failures?

If growth is desired, should I consider any random flavor of linux with the multi-disk manager Mdadm and mdadm gui instead? Or some other option?

I'm concerned on making sure I make the easiest choice here for dealing with failures and long term expansion to grow beyond 8TB (if the linux/freenas options even equate out to nearly 8TB on 3, 4TB drives combined with single parity minimal)?


So quick summary is this:
1. I'd like to have 1 or 2 drive failure ability (raid 5 or 6 later on)
2. Be able to grow the array later on
3. Be able to stream at least 2 blurays at once (though really this is only ever going to be 1 at a time for now I think) to my Home Theater PC over gigabit
4. Have a web gui for managing and have alerts on failure

*it may also be nice to host gui apps for HTPC needs as well, ones supported in linux, but not a requirement, hence FreeNAS becomes one option since i may or may not need this, i think.

I'm assuming my hardware pick is more than fine as well.

Thanks for any tips here

 

[gpsguy]

Frankly, given what you've said, Server 2012 and it's Storage Space subsystem might be a better solution, though I don't have any experience with it, yet.

.. i'm primarily a windows person, so this area is very foreign to me

Spend more time studying the manual. And, read the messages in the forum to get some ideas about the pros and cons of going with FreeNAS. I probably lurked for 3+ months, reading messages, reading other resources, etc., before making the decision to go with FreeNAS.

That being said, with the 4Tb drives and thinking about further expansion, you'll want a motherboard that can accept 16+ Gb of RAM. RAIDZ1 has a single parity drive, RAIDZ2 has two. Don't scrimp on the motherboard/cpu, unless you plan to upgrade it later.

As has been said countless times, you cannot grow a vdev. You can add additional vdev's and add them to a pool, but each vdev would need it's own parity drive(s) to provide fault tolerance to the pool.

Lastly, make sure you have backups. RAID <> backup.

 

[ProtoSD]

Also, this post is useful:

Slideshow-explaining-VDev-zpool-ZIL-and-L2ARC-for-noobs!

 

[markm75]

Frankly, given what you've said, Server 2012 and it's Storage Space subsystem might be a better solution, though I don't have any experience with it, yet.



Spend more time studying the manual. And, read the messages in the forum to get some ideas about the pros and cons of going with FreeNAS. I probably lurked for 3+ months, reading messages, reading other resources, etc., before making the decision to go with FreeNAS.

That being said, with the 4Tb drives and thinking about further expansion, you'll want a motherboard that can accept 16+ Gb of RAM. RAIDZ1 has a single parity drive, RAIDZ2 has two. Don't scrimp on the motherboard/cpu, unless you plan to upgrade it later.

As has been said countless times, you cannot grow a vdev. You can add additional vdev's and add them to a pool, but each vdev would need it's own parity drive(s) to provide fault tolerance to the pool.

Lastly, make sure you have backups. RAID <> backup.

I considered storage spaces briefly.. but its only 1 parity support and the reviews on the performance aren't so hot (http://arstechnica.com/information-...aces-explained-a-great-feature-when-it-works/)

The more I look deeper into this, it seems for what i'm doing FlexRaid is a better fit for me along with server 2012 or server 2008.

 

[cyberjock]

I had a Windows Server 2008 R2 server up until last December when I "upgraded to FreeNAS". FlexRAID has its own pluses, minuses and limitations and needs so I won't go into those here.

The article you linked to is only for Windows Home Server. When Drive Extender worked it was super awesome. But when it didn't work, it often ate all of your data with no chance for recovery(hope you had backups!) as a few friends found out the hard way.

Overall, while I think ZFS is the way to go for me and I could list all the ways its better than NTFS or many other file systems, not everyone is able to manage a FreeNAS server well. Many due to experience and many more due to just not willing to do the homework and get it right. FreeNAS really dumbs down FreeBSD a lot to make it easier for the user but it still requires you to "know your stuff". If you are worried that you don't I wouldn't recommend you jump into FreeNAS until you do. Your data may depend on you making the right choice for you. Unlike Windows which has alot of limitations compared with FreeBSD and Linux, you can do things that can later result in data loss without any warnings. This is not a limitation of FreeBSD/FreeNAS but a limitation in the administrator needing to thoroughly understand what he/she needs to do.

 

[markm75]

How are the read and writes with a typical 3 or 4 disk array with sata III on some of these varieties..

I've read some numbers with snapraid and sync showing 400 MB/sec.. while others like Unraid and FlexRaid tend to be around that of a normal single disk speed in the 100-130 MB/sec range for reads and writes..

how does freenas compare?

Are all disks spinning when the array is being accessed with freenas.. Is the only one out there that supports striping that of ZFS? (or maybe MDADM as well?)..

What is the most drives you can have in a freenas array?

Thanks again

 

[cyberjock]

The speeds vary depending on many many factors. Typically, I'd expect that best case(no other bottlenecks limiting performance) you should see anywhere from 150-300MB/sec from a RAID0 of 4 disks. Perhaps as low as 100MB/sec for a RAIDZ2 with 4 disks. The amount of RAM you have, the "fullness" of the zpool, CPU speed, compression settings, dedup settings, etc all can have major bottlenecks to hard drive speeds.

Yes, all disks are spinning when an array is accessed.