[Gluster-users] Best practices?

[Greg_Swift at aotx.uscourts.gov]

"Larry Bates" <larry.bates at vitalesafe.com> wrote on 01/24/2012 08:34:03 AM:

> I'll admit to not understanding your response and would really
> appreciate a little more explanation.  I only have two servers
> with 8 x 2TB each in AFR-DHT so far, but we are growing and will
> continue to do so basically forever.

I added a bit more clarification in my last response.


> Q: If you are putting all your bricks into a single AFR-DHT volume
> does any of this matter?
A: If there is only one volume, then this is fairly mute.  Othewise, its
depends on the number of filesystems (leading to separate bricks) and the
number of volumes.

> Maybe I'm confused but it seems by keeping the drives as individual
> bricks and using Gluster AFR-DHT to consolidate them into a single
> volume you are:
>
> 1) Maximizing your disk storage (i.e. no disks lost to RAID5 or
> RAID6 overhead)
>
> 2) Limiting rebuilds due to disk failures to a single disk pair,
> thus shortening rebuild times and making rebuilds pretty clearly
> defined.
>
> 3) Making it easier to grow your volume because it can be done by
> adding only 2 drives/bricks at a time (which couldn't really be
> done if you consolidate via RAID5/RAID6 first).

All valid thoughts.  Personally, I prefer to never have to mess with
gluster just because I lost a disk in a RAID set.  Moving large amounts of
data around due to unplanned failures is way more costly to me than loosing
1-2 disks capacity per raid set.

Our original intention was to minimize administrative overhead.  There are
benefits to consolidating your disks into as few filesystems to be
presented as bricks as possible when you a large number of volumes or a
large number of disks.

-greg