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Re: Experiences with BTRFS -- is it mature enough for enterprise use?




tl;dr:
save yourself the hassle and dont. go for md-raid5/6 + (luks +) XFS.

long version:

Just last week we migrated our soon to be production server (6 disks)
btrfs-raid10 to md-raid6+XFS, after btrfs managed to die twice in december.

So cool btrfs-raid/filesystem-level-raid sounds, so broken it seems atm :(
Not only did they not manage to use "common" definitions of raid - as
in: md-raid being de-facto-standard, they get to define certain aspects
of raid and others have to live by that ...

READ THEIR DOCS + MAILING LIST!

For example: when people talk about raid1 with say 4 disks, they expect
that all disks have the same contents... Therefore expecting that losing
3 disks means no data loss.
Well... btrfs decided to stick with some ancient definition of raid1
which is imho more like md-raid10, than md-raid1, as there are only 2
copies of data and you cant make btrfs to store more than 2 copies.
Therefore losing 2/4 disks -> btrfs irrecoverably broken.

btrfs-raid1 and btrfs-raid10 seem to be basically the same thing, with
some imho performance optimizations (not striping vs striping), which
should imho not even be user-settable as it makes no sense to go for
suboptimal performance, but then again, maybe i missed some of their
nearly inexistent documentation pointing out the good part of
btrfs-raid1 ...

Also btrfs-raid5/6 are broken and didnt even survive our in-vm-testing,
before getting a chance on bare-metal.


Also it seems way easier to go "full-raid-encryption" with luks + md-raid.
(Our intention is to be able to send in disks to get them replaced
without having to worry, that data could be easily extracted; there is
an usb-stick with the luks key sticking out of every machine...)

If you need some btrfs-features (snapshots <3), consider going
md-raid+luks+btrfs.
* Unsure if it still holds that btrfs will fail horribly if it sees its
uuid on more than one disk, possibly making the
full-disk-encryption-layer mandatory.

br,
Jan


On 12/26/17 20:37, Rick Thomas wrote:
> 
> Is btrfs mature enough to use in enterprise applications?
> 
> If you are using it, I’d like to hear from you about your experiences — good or bad.
> 
> My proposed application is for a small community radio station music library.
> We currently have about 5TB of data in a RAID10 using four 3TB drives, with ext4 over the RAID.  So we’re about 75% full, growing at the rate of about 1TB/year, so we’ll run out of space by the end of 2018.
> 
> I’m proposing to go to three 6TB drives in a btrfs/RAID5 configuration.  This would give us 12TB of usable data space and hold off til the end of 2024 before needing the next upgrade.
> 
> Will it work?  Would I be safer with ext4 over RAID5?
> 
> Thanks in advance!
> Rick
> 


-- 
lg
Jan Vales
--
I only read plaintext emails.

Someone @ irc://irc.fsinf.at:6667/tuwien
webIRC: https://frost.fsinf.at/iris/

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