Advice for new system

[bdaniel7]

Hello everyone,

I've been planning to setup my first FreeNAS system, inspired from this, this and this (although I don't know what mobo is used in the IX system).

While waiting for the cash to come in, I have some issues to clarify and I hope you can help me.

The requirements for the system are:
1. to keep my files (media files and backups) reliably, so I want to have a mirrored RAID.
2. in case something goes wrong with the mobo/disks, I'd like to be able to recover my data with highest probability.
3. use as little as possible electricity - to keep it on 24/7.


So far, this is the configuration:

Motherboard: ASRock A75 Pro4 (has RAID 1, supports 32 GB of RAM, has 4 memory slots, has onboard video, has at least 4 SATA-III slots)
CPU: AMD Vision A4-3300 2.5GHz box (seems fast enough and not power hungry, has integrated graphics)
RAM: Corsair Vengeance 8GB DDR3 1600MHz CL8 Dual Channel (or maybe 16 GB, haven't decided yet)
HDD: 2 x WD 1TB SATA-III 7200 rpm 64MB Caviar Blue (so far 1 TB is enough)
Case: Fractal Design Define R3 Black Pearl (I heard is very silent, currently is on 25% sale)
Power: Chieftec A-80 350W
Cooling: Arctic Cooling Freezer 7 Pro rev. 2

All for about 650 USD.

I'm planning that in a year or so to upgrade the disk space with another set of 2 disks set up in mirror.

So my questions are:

1. Is it really necessary to have a RAIDZ setup? Isn't a mirror enough?
2. Is it better, in terms of data security, to have a software RAID instead of hardware RAID? Isn't software RAID slower than hardware?
3. To have an easier upgrade of disk and RAM, should I go with ZFS or hardware RAID?

Thank you very much,
Daniel

 

[bdaniel7]

Nobody can answer the 3 questions?
Have I posted this to the wrong forum?

 

[Stephens]

1. Your data, your experiment. You have to make your own decision. You should learn the pros and cons of each and apply them to your situation.
2. Data security has many meanings. What are you securing against? Crashed hard drives? Software RAID need not be slower than hardware RAID these days.
3. ZFS and hardware RAID aren't exclusive. But to answer your question, I'd go with software RAID just like the documentation suggests. Did you read the documentation?

Have you read noobsauce80's ZFS primer? The way you're talking about expanding your space, it sounds like you'd want to add a 2nd vdev composed of 2x1TB drives in a year. I think if both drives in either vdev fail, all the data on the other vdev will be lost too. That is one of the reasons it's better to build what you need up front and not piecemeal. Why wouldn't you just get 2TB drives now and skip all the future upgrading? The cost increase is miniscule.

- For the same 4 drives you planned to have in a year, you could set up a 4-drive RAIDZ2 which would allow you to lose any 2 drives and STILL be able to access all your data.
- Blue drives aren't the most energy efficient and you said you care about that. You'd want Green or Red for that.
- RAM needs power. 32GB is way overkill for 1TB of data (unless you plan on doing something ram-intensive on the box that isn't listed above). The general rule is 1GB of RAM per 1TB of data.

 

[bdaniel7]

Hi,

Thanks for the reply.

Yes, I have read noobsauce80's tutorial (in pdf) a couple of times and re-read after your reply.
And I've also read the documentation, especially the Hardware requirements and Volumes pages (the second time more thoroughly).

But I guess I wanted a more detailed opinion, from someone who actually used those types of RAID.

I was uncertain about the software RAID because I've only used hardware RAID (under Windows 2003 Server) which performed very well.

About Blue vs. Green/Red disk drives, I know the Blue ones are not the most economical, however I need their speed when transferring files. And I guess that if I'm transferring files from/to the disk, the disk is not used, so it doesn't use too much power.

 

[cyberjock]

But I guess I wanted a more detailed opinion, from someone who actually used those types of RAID.

So are you saying I don't use those RAIDs and I just talk about it? J/K. I'm busting your chops because I can :)

I was uncertain about the software RAID because I've only used hardware RAID (under Windows 2003 Server) which performed very well.

About Blue vs. Green/Red disk drives, I know the Blue ones are not the most economical, however I need their speed when transferring files. And I guess that if I'm transferring files from/to the disk, the disk is not used, so it doesn't use too much power.

Remember, your zpool only needs to be able to meet your LAN speeds. If you are using Gb LAN, then 133MB/sec is all you need. So 3 disks can probably do more than twice that in a RAID-0, even "green" drives. I'll totally agree that hardware RAID can almost certainly smoke a software RAID performance-wise. But, who cares if you can do 5GB/sec if you are ultimately limited to 1Gb LAN speeds?

It's all about realizing where your bottlenecks are and not trying to create a superpowerful(read: expensive) machine to give you ultra-high performance that is bottlenecked by your LAN.

Keep in mind that a well planned system is low power(read: inexpensive) but is powerful enough to hit whatever bottleneck or performance threshold is good for you(whichever is lower). I have a FreeNAS server with all Green drives. It runs great! I can max out 2x1Gb LAN connections without problems. I get about 550MB/sec with a dd test. Don't spend money on blue drives unless you will actually realize a benefit. I'm willing to bet that since you are asking such simple questions you aren't planning to go 10Gb, so blue drives are an overkill.

 

[bdaniel7]

So are you saying I don't use those RAIDs and I just talk about it? J/K. I'm busting your chops because I can :)

I didn't say that.

I was expecting feedback from the people who actually built and used FreeNAS and ZFS.
Maybe you should publish some configurations you've built in the Resources area... :p

Anyway, thanks for your feedback.

 

[paleoN]

1. I don't understand the question.
2. I guess this should actually read Is it better, in terms of data security, to have a ZFS array instead of hardware RAID? The answer is ZFS.
3. This also doesn't make sense. Though ZFS is more flexible with individual disks I suppose. Depending on what you are trying to do.

I'll totally agree that hardware RAID can almost certainly smoke a software RAID performance-wise.

Nit, "hardware" RAID with NVRAM cache can smoke a software RAID without said cache.