Rockstor, a Linux and BTRFS Based NAS Solution

by schakrava • 12 years ago

71 49 12 years ago

yawniek4• 12 years ago

the gui looks pretty cool. personally i would not trust btrfs for a nas. i have made not the best experience while running various production servers with btrfs. i switched (back) to zfs and never looked back, it its just better in every regard.

i also administer a freenas box for a small business and this stuff is rock solid, i would only wish a _easy_ solution to get the permission stuff right in a multi user setting.

none the less, thumbs up for creating this, cool stuff!

nisa3• 12 years ago

I'm in the process to rolling out btrfs on a lot of production servers (no raid, just subvolumes and compression) using Ubuntu 14.04 - what problems did you encounter with btrfs?

cjbprime• 12 years ago

I've hit problems like reaching ENOSPC (even though the data extents were only 70% full) on a colocated server, and there isn't enough free space to run a balance operation to get more free space. (The docs literally suggest inserting a USB stick and adding it to your array to help make the balance work..)

Also, the fsck tool is still very immature. It takes many years to get good at detecting and recovering from corruption.

richardkmichael2• 12 years ago

If you don't already, I strongly recommend lurking on the btrfs mailing list. There are regular fixes to balancing, ENOSPC, send/receive and the btrfs-progs tools; occasional questions and fixes related to the compression code.

Be prepared to update your kernels and tools often and independent of your vendor. Btrfs-progs will likely need to come from the git repo, so building your own packages for distribution around your production nodes will probably be necessary too.

A word of caution: do not run btrfsck without consulting the wiki and mailing list first, and hopefully knowing exactly what you are doing. There are situations you'll encounter which do not require btrfsck to repair (but rather, other tools instead), and it will potentially make a recovery less likely.

FWIW, I have been watching the list for years, and reading regularly for about 6 months trying to get a sense of stability with respect to the features I want.

I would not put btrfs in production yet. Though, likely soon.. I'd guess another year or so.

polarix• 12 years ago

better in every regard

Can't remove raidz's from zpools, but `btrfs device delete` exists.

feld3• 12 years ago

That's not a bug.

Elhana• 12 years ago

But lacking raid5/6, even N-way mirrors. ZFS is not perfect, but btrfs is not even close in terms of features.

yawniek4• 12 years ago

in a enterprise setting you rarely want to remove devices/space.

schakrava9• 12 years ago

Thanks. We believe it's a matter of short time before btrfs will be trusted enough.

Can you elaborate on the permission-stuff issue you have? We'd love to get it right in Rockstor.

yawniek4• 12 years ago

basically you need to integrate an ldap server with a decent frontend.

jms703• 12 years ago

no afp support?

sciurus• 12 years ago

Since Apple has supported SMB for a long time, and actually made it the default protocol in 10.9, is there much need for AFP?

stock_toaster• 12 years ago

  > Since Apple has support SMB for a long time, and actually made it the default
  > protocol in 10.9, is there much need for AFP?

Time machine backups still require afp I believe -- unless you use the "TMShowUnsupportedNetworkVolumes" option.

victorhooi3• 12 years ago

I'm running AFP on FreeNAS. I also have SMB setup.

I'm using OSX 10.9.4, and I've seen better performance over AFP than with SMB.

So yes, it'd be nice to have AFP support.

wazoox• 12 years ago

Performance of SMB on Mac is only about half of AFP/NFS, and NFS is more complex to manage from an authorization/user management point of view in a Mac environment.

schakrava9• 12 years ago

No, but does is suggestion from our blog work for you?

http://rockstor.wordpress.com/2014/02/24/backup-mac-folders-...

razster• 12 years ago

Demo page gives me an error message. Sends me to https://50.0.94.5/

schakrava9• 12 years ago

Yes, it's a simple redirect. that's where the demo is hosted for now.

victorhooi3• 12 years ago

Interesting =).

I'm currently running Freenas with ZFS.

Would be curious to see how this compares.

The one thing missing for me on FreeNAS is some kind of file search/indexing feature.

I wonder if the fact that this is Linux based will make adding something like that easier.

schakrava9• 12 years ago

Perhaps. I have some ideas about search features. We can also get some cool stats efficiently from btrfs trees also. But I'd love to hear your thoughts. Is it possible for you to give more input on search/indexing that you wish to see? You can even write to us directly -- support@rockstor.com or file an issue on github: https://github.com/rockstor/rockstor-core

victorhooi3• 12 years ago

I've just filed a support ticket here:

https://github.com/rockstor/rockstor-core/issues/484

Hmm, stats - don't know much about this topic, but I'd been keen to hear more about what's possible.

On the file indexing front, I think Recoll and Tracker/MetaTracker are the two most active projects - Recoll being the more active one. Strigi and Beagle are both discontinued.

RickHull• 12 years ago

My very first questions regarding a potential storage solution revolve around data loss:

    1. Can we enumerate the data loss scenarios?
    2. How is drive failure handled?
    3. How may data be corrupted and such corruption detected?
    4. For every data loss scenario, what is the recovery procedure?

Here is all I could find: http://rockstor.com/docs/faq.html#how-do-i-prevent-data-loss...

Of course, there is a wealth of information on such questions for standard RAID, but I would suggest for marketing purposes that rockstor synthesize available information (from the many relevant layers of data management) in a coherent fashion, specific to their product. It doesn't have to be deep, but it should be at least minimally comprehensive and broad, with pointers to more detailed, layer-specific information.

Also, it's fine if the recovery scenario is "restore from backup" for e.g. the scenario where data is deleted by an authorized user. If so, there should be at least a minimal "backup story".

schakrava9• 12 years ago

That is great feedback for us. I've added a documentation issue with your feedback: https://github.com/rockstor/rockstor-doc/issues/37

We have added appliances <-> appliance replication recently, which can play an important role in recovering from bigger disasters.

We'll have all that documented. Please feel free to participate on our github.

aliamir• 12 years ago

This looks pretty cool. Easier to use and nice gui.

ChuckMcM3• 12 years ago

The only data protection options I could find were Raid 1, and 10. (raid 0 is a performance option) and as data loss on attempting to re-silver a 3TB mirror is 1 in 5, data protection here is not enterprise quality yet).

The UI stuff is great, but the tricky bit about building a storage system is not provisioning it, or getting the access protocols right, it is all about finding all the ways that data can be destroyed (both silently and noisily) and guarding against them. So if you want to stick with the Enterprise target, then you need something like the ZFS On Linux page which describes every way you can get data zapped and how you will prevent that from happening.

If you want to be just an off the shelf "hey here's something that will make your access point into something like a NAS device." then you get to lose data when a disk goes bad, or a memory chip goes bad, or a network cable is loose, or the powersupply cuts out, or the cat knocks it off the table etc.

feld3• 12 years ago

Where did you get your hilarious "data loss on attempting to re-silver a 3TB mirror is 1 in 5" statistic from?

ChuckMcM3• 12 years ago

The non-recoverable bit error rate spec.

NetApp tracks it with their Nearstore product line which used SATA drives in a NAS box (they have been for a while actually, when I left they had data on about 65 million drive hours) and while Seagate quotes it a 1x10^15 bits but its actually closer to 5 in 10^15 bits. A 3TB drive has 3x10^13 bits of data (closer to 3x10^14 when you account for track markers and error recovery bits).

If you're bored some time try reading every sector from one of these drives. To maximize your chance of success make sure you operate the drive at a slightly warm temperature (keeps the lubricant from sticking) and isolate it from vibration. Its worse if you read it randomly (you will get some arm servo movement just because the drive will have replaced some blocks from spares, but minimizing it also keeps vibrations down.)

Long before it became an issue on single drives, like it is today, it was an issue when trying to reconstruct a RAID4 (or 5) group that was 3.5TB (which at the time was a 7 disk raid group of .5T drives. 14 disk groups (a full shelf) were pretty much guaranteed to see a second error in the shelf during reconstruction. Which was also way RAID6 or dual-parity RAID became a must have enterprise feature back in 2005 or thereabouts.

On an interesting side note, because the chance of hitting an unrecoverable read error is evenly distributed through a drive, 3X replication is still recoverable even with intermittent read failures. There isn't really a RAID number for that but it does work reasonably well and avoids a pesky parity calculation if you embed check data in your blocks as they do in GFS.

[1] https://www.usenix.org/legacy/publications/library/proceedin... -- Peter Corbett's paper (he is the guy who invented NetApp's dual parity system, and from that paper the following --

"Disks protect against media errors by relocating bad blocks, and by undergoing elaborate retry sequences to try to extract data from a sector that is difficult to read [10]. Despite these precautions, the typical media error rate in disks is specified by the manufacturers as one bit error per 1014 to 1015 bits read, which corresponds approximately to one uncorrectable error per 10TBytes to 100TBytes transferred. The actual rate depends on the disk construction. There is both a static and a dynamic aspect to this rate. It represents the rate at which unreadable sectors might be encountered during normal read activity. Sectors degrade over time, from a writable and readable state to an unreadable state."

And in experience from the field put it at about 15TB transferred, so 3TB into 15TB, one in five.

schakrava9• 12 years ago

Thank you, I couldn't agree more. It's a tall order and we have work cut out.

I've started to do some DR testing myself, but it will take a little while to publish our findings and recommendations.

rbanffy• 12 years ago

raid 0 is a performance option

Once I won a bet that RAID 1 was actually faster than RAID 0 on a given scenario.

madmaze• 12 years ago

Guys, you might want to remove that RSA Private Key. https://github.com/rockstor/rockstor-core/tree/master/certs

schakrava9• 12 years ago

Thank you and appreciate your issue submission on github. We'll fix this right away.

spacefight• 12 years ago

It's still there.

zachberger• 12 years ago

All three of the server hardware suggestions are discontinued.

gourneau• 12 years ago

Anyone have suggestions for better servers? I wonder if Rockstore would work well with the backblaze case. Maybe some of the OCP cases would work. Anyone played with those?

schakrava9• 12 years ago

I wish I knew first hand how Rockstor would work with backblaze. But 45drives can ship them with CentOS which is what Rockstor is based on.

I've had the opportunity to install Rockstor on various hp gen7 and gen8 servers and had no problems.

I witnessed Rockstor install just fine on an old Isilon node and was told that the performance was quite good -- sorry I have no specifics.

akclr• 12 years ago

Good stuff guys!

Rockstor, a Linux and BTRFS Based NAS Solution

Related Stories