[Lustre-discuss] What says an OST is deactivated?

[Chris Worley]

On Tue, Mar 25, 2008 at 2:13 AM, Andreas Dilger <adilger at sun.com> wrote:
> On Mar 25, 2008  01:28 -0600, Chris Worley wrote:
>  > I do an "lctl dl" and it shows "UP" in the first column for all
>  > OST's... even though I've deactivated many disks.  "iostat" shows the
>  > disks are still in use too.
>
>  What does it mean when you say "deactivated many disks"?
>
To deactivate the disk, I use an incantation like:

lctl --device ddnlfs-OST001f-osc deactivate

...but new files are still going there, and, if I'm reading it right,
the disk is still "up" in Lustre:

# lctl dl | grep 1f
 36 UP osc ddnlfs-OST001f-osc ddnlfs-mdtlov_UUID 5

>
>  > I'm trying to get rid of slow disks... what's the right way to tell
>  > Lustre to quit using a disk?
>
>  If you deactivate an OST on the MDS node it will stop allocating new
>  files there

For now, that's all I want to do... but new files are still going there.

... both a way to deactivate the disk and a way to know which are
deactivated would be nice.

Thanks,

Chris
>, and if your files are deleted by some process (e.g. aging
>  or jobs running) the inactive OSTs will eventually become empty.  If
>  you want to speed this up you should use "lfs find -o {OST}" to find
>  files on that OST and copy them to a new file.
>
>  If you deactivate OSTs on the client nodes and stop the OSTs then the
>  clients will return IO errors for any files remaining on those disks.
>  I doubt that is what you want.
>
>  Cheers, Andreas
>  --
>  Andreas Dilger
>  Sr. Staff Engineer, Lustre Group
>  Sun Microsystems of Canada, Inc.
>
>