bdt
Executive Member
Don't the commercial NAS boxen format their drives as ext(something) that is readable outside of the box?
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NAS storage
- Thread starter Bumzilla
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Not trying to scare you. It's just the truth.
Have you considered the following scenarios with a ready made NAS:
What happens if the hardware fails?
- Will you be able to buy another? (eg. what if they stop selling it?)
- If you can buy another will it need the exact same firmware as your previous model? (can you downgrade and is it still available?)
- Will it be able to recover your data without having context of it? (eg. if you lose your NAS config files?)
- If it does need context, is it possible to carry it over? (eg. is it possible to get the NAS config files if they are required?)
Secondly:
- What kind of RAID does the system use?
- How does it work?
- What are the known limits and problems?
Proprietary RAID is very dangerous because RAID isn't a standard. You have to hope that they implemented it correctly and tell you about the limitations and problems.
FreeNAS uses ZFS which is used in both FreeBSD and Solaris and incredibly well documented and widely used in both Enterprise space and user space.
If you have a complete hardware failure you only need to move your hard drives (not even in the correct order) to another system and import the array.
You don't need specific versions of FreeNAS because ZFS is compatible with old versions of the file system (if you are running an older version like ZFS v15). FreeNAS itself is just a nice GUI over ZFS. Even if FreeNAS no longer exists you can still recover your ZFS array with Solaris of FreeBSD.
All the information about FreeNAS is on the web and guides on how to use it and set it up.
ZFS has an entire wikipedia article explaining in detail how it works.
Really don't see why anyone would take a proprietary system with no guarantees over an enterprise file system with cross OS compatibility and proven stability.
With a HP Proliant FreeNAS is also the cheapest solution. IMHO there is no competition which to choose.
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tRoN
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So u saying there is no way to retrieve the data from a readymade NAS box?
Anyone else have any experience with synology?
ZFS pwns most alternatives:
http://www.unixconsult.org/zfs_vs_lvm.html
Also, ZFS actually has mechanisms to deal with bit rot.
http://en.wikipedia.org/wiki/ZFS
Drunkard #1
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ZFS is probably great. The best RAID system out there. But...
Normal people have more mundane problems than the ones ZFS is designed to solve. Like what case to use, what hard drives to use, wanting a basic system with expansion capabilities, not being able to hold a lifetime's supply of identical replacement disks. Basically, we want Drobos, but cheaper and faster and open source (for repairability). We want 5 storage bays (for 2 drive redundancy), easy expansion (with a Drobo, you pull out the smallest disk and put in a bigger one, and the system sorts everything out), low costs, high reliability (because we can't afford mirrored systems, or 12TB tape streamers for our pron and series collections) and easy repair.
Maybe ZFS can provide this, maybe not, and how easy is it to implement? Most of us don't know.
Normal people have more mundane problems than the ones ZFS is designed to solve. Like what case to use, what hard drives to use, wanting a basic system with expansion capabilities, not being able to hold a lifetime's supply of identical replacement disks. Basically, we want Drobos, but cheaper and faster and open source (for repairability). We want 5 storage bays (for 2 drive redundancy), easy expansion (with a Drobo, you pull out the smallest disk and put in a bigger one, and the system sorts everything out), low costs, high reliability (because we can't afford mirrored systems, or 12TB tape streamers for our pron and series collections) and easy repair.
Maybe ZFS can provide this, maybe not, and how easy is it to implement? Most of us don't know.
Yeah... you might wanna read up on it... your post shows you are not understanding FreeNAS and ZFS. Most people dont know what a NAS is any ways, so if you are working with NAS, you should have the technical ability to use FreeNAS. Its actually dead easy.
Drunkard #1
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From what I could find (and it wasn't easy to find), a 4 disk ZFS system would have to be entirely rebuilt, ie: back up all your data and reformat the disks, if I wanted to expand it to a 5 disk ZFS system, or I lose all redundancy or something. Swapping a 500GB disk for a 3TB gives no increase in space. Replacing a dead disk means command line instructions and system downtime. Is this true?
These are the sort of things that are fine for an enterprise with an unlimited budget for multiple live servers and endless space, and I'm sure they don't mind these problems if they gain 0.01% in reliability, but for an oke who just wants to move his media out of his desktop case, and make better use of his disks than straight mirroring to USB drives, is ZFS the best bet?
That sounds like a raidz issue and not a zfs issue. To resize a raidz setup is more complicated and would require more work. However, if you setup your FreeNAS in striped, you should be able to do all of that.
The things you are describing require a half way competent technician at R300 an hour... You certainly dont need "enterprise" level support or an unlimited budget. You can use any small town technician with half a wit.
Yes its ideal. Just setup the disks in striped instead of raidz mode. Its really really not complicated. Its also very useful for people doing this on the cheap (ie, most home users). You can use your own older hardware and some spare drives. No need to purchase a complete NAS unit to start off with.
Drunkard #1
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The point of a NAS (for me) is to avoid simple striping. I can do that on my desktop with an internal and a USB external, using SyncToy (as I'm doing now, for 3TB total). With RAID 6 (or raidz2) I can get better than 50% usable capacity and 2 drive redundancy. Drobo gives me both of these things in an easy to use, but slow, expensive and worryingly proprietary system, but at least I get the expansion capability and ease of repair.
I was hoping to use my MicroServer as a NAS, but the more I research this, the more I go back to just adding another 3TB internal and external. the 4 storage + 1 cache + 1 system (USB) bays on the MicroServer are too few, and FreeNAS (in raidz2) is more restrictive than Windows. Where are the benefits?
HP Micro Server best value for money and load freenas on it
you can max it out to 19TB with a few tweaks
specs
http://www.myhtpc.co.za/wiki/index.php?title=Main_Page
some readup reviews
http://www.istartedsomething.com/20...r-for-home-small-business-comes-to-australia/
PS. running 3 micro servers fully networked with a total of 35 TB split over them
you can max it out to 19TB with a few tweaks
specs
http://www.myhtpc.co.za/wiki/index.php?title=Main_Page
some readup reviews
http://www.istartedsomething.com/20...r-for-home-small-business-comes-to-australia/
PS. running 3 micro servers fully networked with a total of 35 TB split over them
I'm confused what you mean? Do you mean the fact that you cannot expand the volume (say 3 disk RAID-z to a 4 disk RAID-z) is why you prefer the Drobo?
Because you have posted a lot of misinformation here about ZFS. For example that it is complex. It is simpler than any other RAID I've ever used, especially if you have failure situation. I tested many RAID solutions (Windows, Linux, Controllers, etc.). The most configurable, flexible, best documented and easiest to use solution was IMHO ZFS. Windows isn't reliable and that is the only solution that would be more "simple". Systems like Drobo just wrap a nice GUI around a proprietary system. FreeNAS wraps around ZFS. I'm not sure really how it is complex to use FreeNAS considering it is point and click. You don't need to use command line, even in a very bad failure situation.
And that you have down-time. The only way you would have down-time is if your system doesn't support hot-swap (which the Microserver does not). Then your "down-time" is turning off the system, remove drive, put another back in, start. There you array is back up again in 5 minutes. Sure it is rebuilding but it is transparent to the user and during a rebuild the array is 100% available.
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Drunkard #1
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My misinformation comes from the FreeNAS forum:
No answers (and this is from their official FAQ). Both questions that I wanted answers to.
Also from their official FAQ. Note that Drobo can expand a 3 disk system into a 4 or 5 disk system, just by dropping in an extra disk. As I understand it, if your Drobo is full, you just pull out your smallest disk and stick in a bigger one (without warning), give the system a few hours to decombobulate its flux capacitor (or something) and voilà, bigger volume.
From another FAQ. That doesn't sound simple to me. Note the bold part. Not as simple as a Drobo, for example, which is hot swap.
I'm not against FreeNAS. I'd be happy to use it for my mass storage needs, on my MicroServer, but the expansion issues (as far as I can make out) are a major problem for me. I want efficient use of my disks, and not lose 6TB because one 6 disk RAID volume is bigger than two 3 disk volumes. I also don't see a 4 bay MicroServer giving me 2 drive redundancy. Do I need 2 drive redundancy? Well I don't see how I can reliably back up 9 TB of data economically.
The idea of a Drobo doesn't appeal to me either. It's rigid, propitiatory, expensive and slow. But it's cheaper than a 5 bay hot swap server, and it's features are very useful.
I'll probably stick another 3TB into my desktop (with a boer-maak-'n-plan bracket) and mirror it to an external USB drive. Not very efficient, but it seems like my best option for now.
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I have no idea how the readymade NAS box works. I'm saying, YOU need to ask that question! How will I be able to get to my data if it fails?
Huge post there bud but lets cover this step by step.
"Can I start with X number of disks and then add more later? (UFS vs. ZFS)"
Yes and No.
No you cannot expand an existing RAID-z or ZFS Mirror with extra disks. Nothing is preventing you from adding another RAID-z or ZFS mirror and joining that with another RAID-z or any other kind of volume.
In laymen terms: You can have a RAID-5 and join it with any amount of other RAID-5 and RAID-1 volumes. But you cannot expand an existing RAID-5/6/1 with extra disks. You can for example have a RAID-5 + RAID 1 + RAID-0 volume which cannot exist in RAID but can in ZFS.
Yes this is the downside to ZFS, you cannot expand a RAID-z or Mirror with extra disks.
This is by design and it has to do with data integrity and consistency. It is something I doubt will ever be addressed.
"How do I replace a bad drive - Can it be larger/smaller?"
Larger - Yes but you won't get use of the extra space.
Smaller - No.
If you replace all members, one by one, with a larger disk, apparently you can grow it, but don't quote me on that because it is not recommended (between each replace it will rebuild) and I don't know more.
I see your concern is growing. For me it isn't a large problem because I don't often grow my NAS and when I do, I usually buy enough disks to replace my current, so I just copy everything from one RAID-z to another (on the same machine), then remove the old drives and sell them. This can be done between 2 servers or just happen on 1 server if it has enough connector space.
That quote you had about replacing a disk, that is a very old release.
Currently to replace a downed member is a click operation. You'll see the array is degraded, click on it, it'll show the missing member as missing and disks currently on the array. You click on the missing member and click replace. Pick the new drive. It'll re-silver. All from the GUI, very simple.
Auto-resilver was considered for some time but it really isn't a good idea. The GUI doesn't know for sure that you are comfortable with erasing the new disk you put in. It doesn't know if the missing disk is missing because you replaced it or because of a hardware failure. You see my point, it is a situation where the user should explicitly say, DISK X must be replaced with DISK Y. But this is all done from the GUI now, for some time.
Unfortunately FreeNAS changed so often that some documentation is out of date (FAQ for example).
Hot swap is hardware dependant. In FreeNAS you can hot-swap if the hardware supports it (again the HP Proliant does not have HARDWARE support for it).
If your hardware DOES support hot-swap: You still need to tell it, via the GUI, to replace DISK X with DISK Y. Again as I said, it is unsafe to just assume that someone is hot swapping a disk and bam start rebuilding. That is just bad practice.
You won't need a power down however.
Well if you cannot backup your data somewhere or at least temporarily move it to another array to make a new one with more disks, then yes, I guess that is a problem.
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Drunkard #1
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Gnome, thanks for the info.
Knowing that a bad drive can be replaced with any similar or larger drive is one point for FreeNAS. I was working on the worst case scenario, that a drive had to be replaced with an identical drive - same model, same size, same firmware, same speed, etc. What about replacing a 7200 drive with a 5900, or a vari speed?
The upgrading question is (for me) easily summed up - you can't upgrade a FreeNAS box. Buy a new one, copy everything across, and get rid of the old one. At least I know now.
It's now just a case of whether I'm happy to live with the restrictions, costs and benefits of the different options. Right now a mirrored 3TB drive for my desktop will cost about R 3300. A 6TB (12TB raw) FreeNAS upgrade for my MicroServer is about R 7800, and I get a static, but fast and reliable system (do I need a caching SSD?). A Drobo is about R 11700 for 6TB (12TB raw), or R 13400 for 9TB (15TB raw).
The Drobo's a bit too costly and the MicroServer can't expand when I fill it within 24 months. That leaves another internal drive with an external mirror - it's the cheapest of the lot, the most "repair friendly", but not the most reliable, and I'll still have 1 SATA port left for a 4TB in two years time. After that my PC will be due for replacement anyway. Pity. I was hoping to set up a reliable, resilient NAS for the whole network. I'll just keep streaming media from my PC.
Knowing that a bad drive can be replaced with any similar or larger drive is one point for FreeNAS. I was working on the worst case scenario, that a drive had to be replaced with an identical drive - same model, same size, same firmware, same speed, etc. What about replacing a 7200 drive with a 5900, or a vari speed?
The upgrading question is (for me) easily summed up - you can't upgrade a FreeNAS box. Buy a new one, copy everything across, and get rid of the old one. At least I know now.
It's now just a case of whether I'm happy to live with the restrictions, costs and benefits of the different options. Right now a mirrored 3TB drive for my desktop will cost about R 3300. A 6TB (12TB raw) FreeNAS upgrade for my MicroServer is about R 7800, and I get a static, but fast and reliable system (do I need a caching SSD?). A Drobo is about R 11700 for 6TB (12TB raw), or R 13400 for 9TB (15TB raw).
The Drobo's a bit too costly and the MicroServer can't expand when I fill it within 24 months. That leaves another internal drive with an external mirror - it's the cheapest of the lot, the most "repair friendly", but not the most reliable, and I'll still have 1 SATA port left for a 4TB in two years time. After that my PC will be due for replacement anyway. Pity. I was hoping to set up a reliable, resilient NAS for the whole network. I'll just keep streaming media from my PC.
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bdt
Executive Member
Gnome, you seem to be the one to ask here so, if you can indulge me: as I said earlier, I have a situation where I am stuck with a server presenting an NTFS share. Would this be feasible by having a FreeNAS box as a backend presenting an iSCSI target to, say a 'doze server (that, one way or another I tend to get stuck with, at least in my home office) so that said server offers up an NTFS volume and all the software is happy with life? Please excuse terminology mangling, I'm new in these waters.
Also check out unRAID, very flexible ito adding more drives later. I run the licensed version of unRAID on my MicroServer. My QNAP TS-410 is still my main box, but I'm busy moving the RAM intensive stuff to the unRAID MS with 8GB RAM ... The lower end QNAP's only have 256MB RAM, so running Sabnzbd+ and SickBeard and a Torrent downloader can sometimes give it a hard time.
Ianf1
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TYR, with paid version of unraid are the read writes faster? Sometimes it takes a minute or 2 to to open a file from the server and we have 8gig ram. Will upgrading help this?
You are probably forgetting that the drives take a while to spin up, but certainly shouldn't take a minute or two.
Extra RAM is unlikely to help I am running 2GB on the free version and no such problems, it takes about 10 seconds for them to spin up initially in my case.
SilverNodashi
Expert Member
What NAS you buy, is your decision at the end of the day. We can only give some suggestions and recommendations, but you need to live with the consequences of your decision - either good or bad.
As an IT company which serve large and small clients in various market sectors:
I can suggest the following:
1. Don't bother spending money on a prebuilt NAS under R20K. They're slow, horrendously slow and gets slower, the cheaper the are. Reason: The cheaper models have slower CPU's, slower RAM, slower NIC's, and slower system busses.
2. You're limited todo what the manufacturer wants you todo, and you're at their mercy for upgrades and new feature releases. Again, the cheaper the unit, the less features and upgrades you can expect.
3. You're generally limited to their chosen filesystem (which may or may not be optimal in general) and RAID setup. Cheap NAS units (sub R10K) don't have hardware RAID but rather software RAID. This has 2 problems: a) you generally only have RAID0, RAID1 and RAID 5. You're lucky if it has RAID6, but RAID10 isn't available, most of the times. b) You'll have a VERY hard time moving the drives to a Linux server, with similar RAID setup and recover your data if the unit fails. And more often than not, you may not be able to recover your data if you were to purchase another identical unit and put the drives in. the new unit's SATA controller version will have changed, and the NAS's firmware adapted accordingly, 2 or 3 years after you brought your first one.
4. There's generally no, or very very limited scalability on the cheap devices. Need more space, buy another unit.
5. Very limited, if it all any security. So you would need to introduce other security measures, which could cost extra money, if the NAS has to go on a company network.
If you go the FreeNAS, Open India, Nexenta (well worth-it) route then you have the following advantages:
1. Speed: You can build the NAS on more powerful QuadCore CPU + 4GB RAM + Intel server NIC + SATA6 PC for ultimate performance. Need more performance? Add 1 or 3 SSD drives for cache and logs. Or use SAS if SSD's are too expensive right now.
2. Open Source means you can add your own features, if you had the skill. Or you can hire a developer if you really needed something which isn't there, and someone else haven't added already. FreeNAS is feature packet far beyond most cheap NAS devices.
3. ZFS is a superior file system. If the box breaks then you simply put the drives in a new box, bootup with your FreeNAS memory stick and you're running in a few minutes. Broken memory stick? No problem, create a new one and the NAS work again. What if FreeNAS goes "out of business"? Use FreeBSD, Ubuntu + ZFS, Open India, Nexenta, etc. ZFS offer more protection than what normal linux RAID can at this stage. You can also use EXT2/3 if you really want to.
4. Need more space? Add more drives. Need even more space? Install a 4 port or 8 port SATA PCI expander card, add more drives, create a new stripe and add the stripe to your ZFS pool. A ZFS pool can scale without downtime or much hassle.
5. Security is part of the OS by default.
How do you build one?
download the FreeNAS image, write it to a USB memory stick, bootup an old PC, pop in 2 drives and setup your NAS
As an IT company which serve large and small clients in various market sectors:
I can suggest the following:
1. Don't bother spending money on a prebuilt NAS under R20K. They're slow, horrendously slow and gets slower, the cheaper the are. Reason: The cheaper models have slower CPU's, slower RAM, slower NIC's, and slower system busses.
2. You're limited todo what the manufacturer wants you todo, and you're at their mercy for upgrades and new feature releases. Again, the cheaper the unit, the less features and upgrades you can expect.
3. You're generally limited to their chosen filesystem (which may or may not be optimal in general) and RAID setup. Cheap NAS units (sub R10K) don't have hardware RAID but rather software RAID. This has 2 problems: a) you generally only have RAID0, RAID1 and RAID 5. You're lucky if it has RAID6, but RAID10 isn't available, most of the times. b) You'll have a VERY hard time moving the drives to a Linux server, with similar RAID setup and recover your data if the unit fails. And more often than not, you may not be able to recover your data if you were to purchase another identical unit and put the drives in. the new unit's SATA controller version will have changed, and the NAS's firmware adapted accordingly, 2 or 3 years after you brought your first one.
4. There's generally no, or very very limited scalability on the cheap devices. Need more space, buy another unit.
5. Very limited, if it all any security. So you would need to introduce other security measures, which could cost extra money, if the NAS has to go on a company network.
If you go the FreeNAS, Open India, Nexenta (well worth-it) route then you have the following advantages:
1. Speed: You can build the NAS on more powerful QuadCore CPU + 4GB RAM + Intel server NIC + SATA6 PC for ultimate performance. Need more performance? Add 1 or 3 SSD drives for cache and logs. Or use SAS if SSD's are too expensive right now.
2. Open Source means you can add your own features, if you had the skill. Or you can hire a developer if you really needed something which isn't there, and someone else haven't added already. FreeNAS is feature packet far beyond most cheap NAS devices.
3. ZFS is a superior file system. If the box breaks then you simply put the drives in a new box, bootup with your FreeNAS memory stick and you're running in a few minutes. Broken memory stick? No problem, create a new one and the NAS work again. What if FreeNAS goes "out of business"? Use FreeBSD, Ubuntu + ZFS, Open India, Nexenta, etc. ZFS offer more protection than what normal linux RAID can at this stage. You can also use EXT2/3 if you really want to.
4. Need more space? Add more drives. Need even more space? Install a 4 port or 8 port SATA PCI expander card, add more drives, create a new stripe and add the stripe to your ZFS pool. A ZFS pool can scale without downtime or much hassle.
5. Security is part of the OS by default.
How do you build one?
download the FreeNAS image, write it to a USB memory stick, bootup an old PC, pop in 2 drives and setup your NAS
Ianf1
Expert Member
Today the server was quick yesterday it was slow so who knows?