On Tue, 18 Feb 2014, Toby Corkindale <toby@dryft.net> wrote:
On 18 February 2014 14:30, Russell Coker <russell@coker.com.au> wrote:
On Tue, 18 Feb 2014, Petros <Petros.Listig@fdrive.com.au> wrote: BTRFS doesn't have any sort of RAID-5/6 support that's remotely usable. RAID- Z/Z2/Z3 works really well on ZFS.
If you use a BTRFS root filesystem with systemd then you can't balance or scrub the filesystem because systemd journal file use triggers a BTRFS data corruption bug. But then root on ZFS is pretty much unusable on Linux anyway.
The version of btrfs that ships with Ubuntu Saucy supports RAID levels: 0, 1, 5, 6, 10 You can mix and match, so metadata gets mirrored while data gets raid5, for instance, if you really want.
There are bugs in the code for balancing and regenerating data from parity. So while BTRFS will technically support RAID 5/6 if you have a hardware failure and need to recover then you may need to wait for new kernel code that hasn't been written yet. BTRFS does support RAID-10, the way it does RAID-1 makes it RAID-10 if you add more disks.
I've been running btrfs as root on a few systems, and they've all been fine. Note that they're Ubuntu though, so they'll be Upstart, not systemd,
Yes, upstart doesn't do the logging stuff that systemd does so doesn't trigger that bug. sysvinit is also OK.
and with almost certainly later versions (and more heavily patched versions) of the linux kernel. But presumably available on Debian via some backports.
No. The latest kernel in Debian/Unstable doesn't have a fix. 3.13 fixes it and I think there's a new kernel.org kernel in the 3.12 series that does it. But it's not in Debian/Unstable yet. I haven't checked Debian/Experimental. -- My Main Blog http://etbe.coker.com.au/ My Documents Blog http://doc.coker.com.au/