+- Kodi Community Forum (https://forum.kodi.tv)
+-- Forum: Discussions (https://forum.kodi.tv/forumdisplay.php?fid=222)
+--- Forum: Hardware (https://forum.kodi.tv/forumdisplay.php?fid=112)
+--- Thread: FreeNAS versus unRAID as the operating-system for a DIY NAS? (/showthread.php?tid=82811)
- darkscout - 2010-10-13
TugboatBill Wrote:Everything I'm finding on "bit rot" for hard drives boils down to:
1. The hard drive has CRC error checking built in which corrects virtually all "bit rot".
Not quite.
Quote:3. "Bit rot" appears to be more of a ZFS "sales" feature than anything else.
And snapshotting (not important for Movies/TV shows, but for my documents). De-duplication, ACLs, COW, on disk compression (up to gzip-9), ...
Quote:media storage system in a home.
I'll say it a THIRD time. IF you are only building this to house your media. Go with unRAID, JOBD, etc.
If you are building a generic home server house Pictures, Documents, your TimeMachine backup or anything that you really want to make sure is backed up and is being saved correctly. Use ZFS.
- poofyhairguy - 2010-10-13
froggit Wrote:You can use different sized drives, but the smallest capacity will be used. E.g. 500GB, 1TB drives used, will only give 500GB capacity for a mirror.
So yes you can do this, but in reality you plan ahead and chuck a bunch of same-sized drives into a new vdev when expanding the pool, or building a new system.
Then there is the main disadvantage of ZFS compared to Unraid.
With my Unraid box when I need more space I can go on Newegg and buy ANY hard drive I want of any size, add it to my array and enjoy all the space on the drive while still having a single drive for parity.
Many consumers don't like buying all their drives all at once, and that is why commercial consumer solutions for servers like WHS advertise the ability to mix and match drive sizes above everything else they do.
In fact from what you are telling me, ZFS seems to be a slight disadvantage to my old RAID 5 server in that you can't add drives to existing vdev.
So basically with all the vdevs you end up with a server with MANY different arrays that have pooled storage. But it seems you can't add single drives and get parity protection on those drives- you have to at least add two drives!
At least my old RAID 5 server would let you grow the array and add additional drives of the same size later without "wasting" more space on parity.
Quote:ZFS was designed for business users, where the prospect of adding 4 or 6 drives etc does not make the person cry about the cost of the drives.
Which is why I think Unraid is a better home media server solution for people that DON'T want to buy every drive in their 20 bay Norco at one, yet don't want to waste more than one drive for parity in that Norco through its entire life as a server.
Quote:This gave me the capacity of all the drives added together, so no capacity was lost. But crucially, this configuration had no redundancy, as the vdev specified no parity, so if a drive died I would lose everything because the data is striped across the drives.
That is nothing special, just a fancier JBOD. What makes Unraid special is you can have that exact same setup AND have parity protection. That is why some people (like me especially) are willing to pay for it.
Quote:To me, my data is still data regardless of what type of data it is, and I am not willing to lose any of it, or go through re-ripping exercises, identifying movie folder names accurately again prior to XBMC library scraping. This is time I simply do not have, or at least am not willing to do again. And for those reasons, I am not willing to lose any data.
It seems like it comes down to how you fear losing your data.
You fear "bit rot" and the fact that Unraid/RAID 5 only has one parity drive. Hence you use ZFS.
I fear drives wearing out because you have to run them all the time in a stripped array, or that if one more drive is lost during a rebuild than I had in parity than all my data is lost. Hence I use Unraid.
Quote:But each person is different, and so each person needs to decide what's important to them and choose a solution that fits their needs.
This is where I completely agree 100%. No solution is perfect, and they all have downsides.
For me personally all I wanted was a media server that gave a least a little parity protection (so if a drive dies), while allowing me to mix and match drive sizes so I can always buy what is cheapest at the time I need the space. Bonus that Unraid runs off a pen drive to allow me to use all my sata ports for storage, and that Unraid has a super tweaked SMB that makes the default SMB setup in Ubuntu seem like a snail.
You wanted a business class system with all the features you mentioned. Which is awesome.
Each to their own, and both are capable of streaming a Blu Ray rip to a XBMC box. That is all that really matters in this context.
- jvdb - 2010-10-13
poofyhairguy Wrote:Bonus that Unraid runs off a pen drive to allow me to use all my sata ports for storage
If you have a motherboard that supports them, I highly recommend these over a pen drive:
http://www.logicsupply.com/categories/flash_storage/usb_flash_modules
It uses wear leveling and has SLC NAND. I run my FreeNAS from a 1GB one. (was previously using a Patriot XT drive that failed, now I only use pen drives for OS backup.)
- darkscout - 2010-10-13
I finally got unRAID running running on VirtualBox (no small feat since mlabel c:UNRAID would add random glyphs to the end "UNRAID
". So I had to do label X, edit the bzroot to mount LABEL=X, etc). I can't explain how unimpressed I am.
I'm running "version: 5.0-beta2."
Under AFP & FTP it lists "Coming soon!". So there goes my TimeMachine backups.
When adding a user I can't specify the UID, so NFS... well must just be global read/write (I'm on my XP laptop at work so no proper NFS).
(I know you can do "user shares") but by default all I see are "disk1" and "disk2" folders.
I swapped out one of my virtual 10GB drives for a virtual 20GB drive (The scenario you keep repeating). I instantly got the error "Stopped. Disk in parity slot is not biggest." "If this is a new array, move the largest disk into the parity slot. If you are adding a new disk or replacing a disabled disk, try Parity-Swap." Except I can't find the Parity-Swap button.
I also notice that all my data isn't there. Isn't the parity drive just supposed to the missing data? I mean with ZFS I just do a disk swap and I have full coverage, in the mean time NONE of my data is missing.
Fine. Power down. Put the 20GB drive into the parity disk slot... still have only 20GB available (disk1 & disk2).
At which point I get the fun message "WARNING: canceling Parity-Sync will leave the array unprotected!" For another 37 minutes. Meaning if a drunk driver hits a power line, neighbor digs into his power, who knows what else could happen: my data is unprotected.
The Free version only supported 2 disks (3 if you count parity). Free version of NexentaStor supports up to 12TB.
I suppose if I wanted to slap a bunch of drives in a case and have a NAS for unimportant stuff, maybe... then again I'd have to pay for using more than 2 drives. So I'd go with FreeNAS.... at which point I'd just use ZFS.
- froggit - 2010-10-13
teaguecl Wrote:Except that it only runs properly on OpenSolaris - which is dead. I'm on your side that FreeNAS+ZFS is a fantastic solution, but lets not get crazy with the comparison. unRAID works very well for multimedia storage, and is very simple to use - that makes it extremely relevant to many even if it's lacking some enterprise level features.
Or Solaris*. Or Nexenta/NexentaStor**. Or Illumos. Or OpenIndiana. Or Linux through Fuse. Or FreeBSD*
* You can still download it for free.
** Very FreeNAS like
Added FreeBSD to your list, darkscout
- TugboatBill - 2010-10-13
I brought up my unraid box in about 10 minutes the 1st time. Of course I wasn't trying a beta release on a virtual host with a 20+ step process to get it to work.
To reiterate - If you want a data storage system on a server unraid is not the solution. It is designed as a media NAS. Once you try to virtualize it you compromise not only its functionality and stability, you are then using a server - so go with a server based solution. If you want a NAS for your media then unraid is one of the best (if not the best DIY) solution out there.
- froggit - 2010-10-13
TugboatBill Wrote:Everything I'm finding on "bit rot" for hard drives boils down to:
1. The hard drive has CRC error checking built in which corrects virtually all "bit rot".
2. ZFS can offer an additional layer of protection against bit rot.
3. "Bit rot" appears to be more of a ZFS "sales" feature than anything else.
I've worked in IT for quite a while. ZFS is the only file array system I've found that promotes additional protection against "bit rot". Most enterprise organizations don't use it yet seem to get along fine without any "bit rot" problems. Yes, it is an additional layer of protection, but a mirrored raid 6 array gives great protection too - it just isn't applicable in a media storage system in a home.
Bit rot is different to drive failure, which is obvious when it happens.
First, many people are ignorant about bit rot, and secondly not many file systems provide the tools to (1) detect it, and (2) correct it.
If your OS/file system doesn't provide the tools to detect & correct bit rot, then does that mean it's not happening? No, of course not. All it means is that you are blissfully unaware that your files are decaying. Not good.
- TugboatBill - 2010-10-13
Strange that it isn't a topic that is discussed. planned for, or even experienced in the enterprise IT community. It must be important though.
- froggit - 2010-10-13
poofyhairguy Wrote:It seems like it comes down to how you fear losing your data.
You fear "bit rot" and the fact that Unraid/RAID 5 only has one parity drive. Hence you use ZFS.
I fear drives wearing out because you have to run them all the time in a stripped array, or that if one more drive is lost during a rebuild than I had in parity than all my data is lost. Hence I use Unraid.
Then you might like this:
http://blogs.sun.com/ahl/entry/triple_parity_raid_z
http://dtrace.org/blogs/ahl/2009/07/21/triple-parity-raid-z/
Don't have time to give a full answer as it's my birthday today and I'm off out to the pub...
- froggit - 2010-10-13
darkscout Wrote:I finally got unRAID running running on VirtualBox (no small feat since mlabel c:UNRAID would add random glyphs to the end "UNRAID
I can't explain how unimpressed I am.
I'm running "version: 5.0-beta2."
Under AFP & FTP it lists "Coming soon!". So there goes my TimeMachine backups.
When adding a user I can't specify the UID, so NFS... well must just be global read/write (I'm on my XP laptop at work so no proper NFS).
(I know you can do "user shares") but by default all I see are "disk1" and "disk2" folders.
I swapped out one of my virtual 10GB drives for a virtual 20GB drive (The scenario you keep repeating). I instantly got the error "Stopped. Disk in parity slot is not biggest." "If this is a new array, move the largest disk into the parity slot. If you are adding a new disk or replacing a disabled disk, try Parity-Swap." Except I can't find the Parity-Swap button.
I also notice that all my data isn't there. Isn't the parity drive just supposed to the missing data? I mean with ZFS I just do a disk swap and I have full coverage, in the mean time NONE of my data is missing.
Fine. Power down. Put the 20GB drive into the parity disk slot... still have only 20GB available (disk1 & disk2).
At which point I get the fun message "WARNING: canceling Parity-Sync will leave the array unprotected!" For another 37 minutes. Meaning if a drunk driver hits a power line, neighbor digs into his power, who knows what else could happen: my data is unprotected.
The Free version only supported 2 disks (3 if you count parity). Free version of NexentaStor supports up to 12TB.
I suppose if I wanted to slap a bunch of drives in a case and have a NAS for unimportant stuff, maybe... then again I'd have to pay for using more than 2 drives. So I'd go with FreeNAS.... at which point I'd just use ZFS.
Once you've used ZFS, probably nothing would impress -- except *perhaps* NetApp WAFL / Veritas... but these cost much $$$
- bigdog66 - 2010-10-13
darkscout....
I have not built one of any of these solutions yet so i am far from one to answer any of these issues.....other than knowing at least in unraid the parity drive has to match the size or be bigger than the data drives.....also know that you can't stick a new parity drive in and magically it instantly starts working
Now for myself.....and maybe its just me but I am most comfortable in windows
anything else I venture into I know that if I just blindly enter into it clicking away and then whine about it then thats more my fault
Now what I do have a vast knowledge of and experience in was listening (reading) your rant you just went on.....see i have a wife so I am completely used to it......
lol.....just busting your chops....
- froggit - 2010-10-13
TugboatBill Wrote:Strange that it isn't a topic that is discussed. planned for, or even experienced in the enterprise IT community. It must be important though.
http://www.enterprisestorageforum.com/continuity/features/article.php/3716796/When-Bits-Go-Bad.htm
http://storagemojo.com/2007/09/19/cerns-data-corruption-research/
https://indico.desy.de/contributionDisplay.py?contribId=65&sessionId=42&confId=257
Enjoy
- poofyhairguy - 2010-10-13
froggit Wrote:Don't have time to give a full answer as it's my birthday today and I'm off out to the pub...
Happy Birthday!
- TugboatBill - 2010-10-13
I considered listing all the possible things that can damage data that have a much higher probability of happening. I realized my list would be huge.
To make it succinct - If you really feel that the vanishingly small probability of bit rot could affect you then by all means set up a server with ZFS. Just make sure you address everything that is of higher risk, which is just about anything you can think of.
Oh, also make sure you place your server in a lead box, cosmic radiation can affect your data too.
- TugboatBill - 2010-10-13
poofyhairguy Wrote:Happy Birthday!
+1