Re: [HPDD-discuss] zfs on linux and lustre
On Thu, Oct 16, 2014 at 09:26:59PM +0000, Dilger, Andreas wrote:
On 2014/10/16, 9:10 AM, "Kurt Strosahl"
<strosahl(a)jlab.org> wrote:
>Good Morning,
>
> Has anyone out there been using zfs as the back end for lustre? I am
>curious as to how you set up raid-z when setting up an ost.
Two options exist:
- specify raidz/raidz2 on mkfs.lustre command line (see man page):
mkfs.lustre {other opts} --ost --backfstype=zfs mypool/testfs-OST0000 \
raidz2 /dev/sd[a-j] raidz2 /dev/sd[k-t] raidz2 /dev/sd[u-z]
/dev/sda[a-d]
would, for example, create three RAID-Z2 VDEVs with 10 disks each. Of
course the use of /dev/sd* device names is frowned upon in real life ZFS
usage, but are shorter for this example.
- create RAID-Z/Z2 datasets normally, then just point mkfs.lustre at them:
mkfs.lustre {other opts} --ost --backfstype=zfs mypool/testfs-OST0000
IIRC you have to disable automatic mounting on the pool (legacy mode).
The xattr=sa option is also needed, for performance at least, if the
dataset is not created by mkfs.lustre.
-Isaac