FreeNAS versus unRAID as the operating-system for a DIY NAS? - Printable Version
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- gabbott - 2010-10-11 03:06
darkscout Wrote:And if you're building a NAS to do both Media storage and your priceless family photos, any documents you may have, etc. Which one would you trust?
Just remember, no matter the RAID system.. RAID is NEVER a replacement for a backup system.
- BLKMGK - 2010-10-11 04:18
I've been using unRAID for well something like 5 years. I was one of the very first users I think and I run two of them. One of them is used for backups of my desktops and the other for movies. I have upgraded more drives than I can count and motherboards too. What unRAID has over systems is the ability to sleep drives when not being used. If I lose two drives, which will destroy many RAID systems, I will only lose two drives worth of data - oh and it's a standard Linux FS that can be recovered. I can throw in any drive size I want so long as the parity drive is as big or bigger. I can use IDE, SATA, whatever all together. Boots from a USB stick too which is nice. As for speed - it maxes out my 100meg ethernet no problem. I have GigE everywhere but I put one of my servers on a 100meg connection and the difference was SO bad I had to rewire it for Gig! An update to SAMBA not long ago really improved speed on this system...
So anyway, I and quite a few of my friends all use unRAID now - it just works...
- Flomaster - 2010-10-11 04:18
whats to say that your "backup system" isn't going to have a failed drive ?
I'd like to learn something, I am currently building an unRaid Media server, I like the idea of having a drive failure and not loosing my data.
- npggefvert - 2010-10-11 04:36
Flomaster Wrote:whats to say that your "backup system" isn't going to have a failed drive ?
Yep, the best way to do it is to have both. I have a fileserver with a Raid5 array, and a JBOD array on my desktop that backs up all the files from the fileserver nightly... Cobian is a very good free piece of software to do this BTW...
- markguy - 2010-10-11 12:33
Flomaster Wrote:whats to say that your "backup system" isn't going to have a failed drive ?
Then you swap in a new drive and it gets rebuilt from the parity drive.
Keep it simple - airjrdn - 2010-10-11 14:49
I've been using XBMC for some time, and one of the nice features is it's ability to add multiple sources all under one "roof" ie; Videos/Music/etc.
When 200G drives were considered large, I had about 12 stuffed into a single case. When problems occurred (cable bad, PATA card loose or something, etc.) it was a bear trying to determine what was wrong, which physical drive was the culprit, etc. and there was always this fear of having to work with a setup that I didn't have extensive experience with. Over the years, I simplified things and set it up with a single drive large enough to hold the content it was meant for, and a mirror for that drive (different make/model) that I synced up manually using FreeFileSync. If I add content, I typically sync it immediately. If I remove content, I'll sometimes wait a few days in case I want it back.
So, now I have one drive for each type of content; kid shows, adult shows, music, pictures, etc. Each has a mirror drive on another machine, and everything but shows is backed up with versioning offsite with Crashplan for about $50/year. Digital camera pics & vids actually have two local mirrors and are also offsite at Fotki as well as at CrashPlan Central.
With four kids, the digital camera content is the most important to me. For those, I have the originals in RAR files with 5% recovery data. For one final layer of protection, parity files are built with QuickPar offering 25% redundancy, meaning they can be used to recreate up to 1/4 of the RAR files.
RAID, unRAID, FreeNAS, FlexRAID, etc. all add a layer of complexity when compared to a single drive with a single mirror drive synced either automatically or manually. If a drive fails, you replace it and are up and going very quickly and simply. If you have content that you'd like to be doubly certain it's safe (ie; my pictures), you can throw a 2nd mirror drive in and call it a day.
Additionally, you can easily transport that 2nd mirror offsite to someone else's house and you are covered in the event of a fire, tornado, or some other disaster.
Just my 2cents, keep it simple, and when a crisis arises, you won't have to have your rocket scientist hat on or be wading through forum posts and online manuals to handle it.
- PatrickVogeli - 2010-10-11 15:01
Your solution is good but only for very valuable data: i mean, one can double 1 or 2 2TB hard drives, but mirror 20 of them?
unRAID is fine at what it does: you can grow up as your collection expands, and, in case a drive fails, recover it. Usually, movies are not important enough to care more about them than what unraid offers.
I already had asked thess questions, but I haven't got answers: how does freenas behave agains a multiple drive failure? Does it allow you to add drives as you need more space? Does it need raid enabled in bios or a hardware raid controller? Can you mix different type of drives (sata, ide, different sizes)?
Zfs nas - froggit - 2010-10-11 20:01
If I can give some tips here, having researched this area extensively 3 years back:
- video storage requires loads of storage
- you need to avoid data loss as much as is possible, hence use ZFS
- you need ability to expand
- you still need to backup all this data, hence need a cheap backup box (repurposed old machine perhaps)
- you don't need amazing transfer speeds for streaming
- go for a fairly low-power CPU solution as NAS speeds are limited by the ethernet connection, typically 50MBytes/sec
- disk speeds don't need to be so fast, so 5400 RPM 3.5" drives are fine for video NAS
- to provide against loss, look for double-parity - i.e. 2 drives can die before data loss is experienced (ZFS RAID-Z2, similar to RAID 6)
- use ECC RAM as it helps guard against junk being stored on the drives
Anyway, take a look at the following results of my research, even if it's a couple of years old, it's still relevant:
AMD Athlon II X2 ‘e’ models: AMD have released interesting low power versions of their dual-core 64 bit processors, for example the AMD Athlon II X2 235e . 45W TDP with CPU frequency scaling to use lower power when the NAS is idle. As with most AMD processors, these provide ECC memory support within the memory controller within the processor package.
Go for a well-supported, reliable socket AM3 motherboard. I have had a lot of success with Asus motherboards using AM2 socket motherboards. Make sure the chipset is well supported (NIC / SATA etc), and has six SATA ports on the motherboard (see drive tips below for why six is a good number).
As video storage requires lots of capacity, you'll want to use large capacity drives. The 2TB drive is currently the largest capacity drive easily available, but high reliability has become difficult for drive manufacturers to achieve. The most reliable consumer-priced drives that I have found this year are Samsung HD203WI drives (4-platter, 2TB, 5400 RPM), which I personally use without any problems/errors detected, and there is a newer model, Samsung HD204UI (3-platter, 2TB, 5400 RPM) which is worth checking out.
Also, to use double-parity (ZFS RAID-Z2 / RAID 6), the capacity of two drives will be used to provide storage for parity data, so to enable a good data-to-parity ratio, a six-drive setup will allow you the capacity of 4 drives for data and 2 drives for parity data, so 2/3 of the capacity is used for data, and 1/3 for parity data. E.g. using six 2TB drives, you'll get approximately 8TB for data and 4TB for parity data.
Finally, let me re-emphasize the importance of using a robust file system like ZFS, which has superb RAID features. Use OpenSolaris build 134, as it is the last release before Oracle clobbered OpenSolaris. OpenSolaris forks called OpenIndiana/Illumos have appeared to replace the open-source OpenSolaris and these will take over from OpenSolaris. Also FreeBSD has a port of ZFS, but the OpenSolaris version is preferable as it has rollback capability so you can recover the OS from a failed upgrade, and this feature is called Boot Environments, or BE as an abbreviation.
Some people also recommend Nexenta, but be aware that this is a commercial company, but there is a free version that allows up to 12TB. Personally, I like to avoid "free up to a point" products, so I chose OpenSolaris. As OpenSolaris is now dead, look for the successors: OpenIndiana/Illumos. Or just install OpenSolaris build 134 now, and migrate to OpenIndiana later once they get properly under way.
Hope it helps, and feel free to ask if you have questions after reading the URL I listed above.
- teaguecl - 2010-10-12 02:30
froggit Wrote:If I can give some tips here, having researched this area extensively 3 years back:I sort of disagree with you here. I don't backup anything on my NAS. If I get a double disk failure, my data is gone - and that's fine. The reason why is that I don't put anything valuable on it. You only need to backup valuable data - that which cannot be replaced. This is typically content you create, that is unique to you, including personal photos, documents, etc. Unless you are generating GB's of content (you are a filmmaker or similar) you don't need to backup your NAS. I have 20 GB of blu-ray and DVD rips on my NAS, and it would be a pain to re-rip them - but it would not be a disaster. I'm pretty sure if my home burned down I could find another copy of Ghostbusters. The videos of the kids and my masters thesis however, are irreplaceable - those really are backed up both locally and remotely.
I would suggest that an UNRAID or Drobo or RAIDZ is more than fine for 99% of the stuff you want to store on your NAS for use with a htpc. It gives you a little protection from disk failure - just enough to ease the pain of re-ripping, but certainly not enough to store really important data on.
By all means back up your important stuff - but don't bother with your DVD rips of Lord of the Rings.
I do not recommend 4KB sector hdd's for linux - pike - 2010-10-12 02:57
Before someone runs out and buys Samsung HD204 hdd's let me tell you why this is a bad idea for *nix raid solutions
HD203 models are no longer being manufactured, if you see it still, that's the last ones. HD203 was a nice drive and was using 512bytes sectors.
HD204 is the model to replace 203. this new drive is not as suited, due to 4Kilobyte sector size, and NO way to make it behave like the old 512byte standard (unlike WD 2TB's hdd's where you have a jumper option atleast.
Now, why is this a problem? Please see here!
froggit Wrote:Drive tips: