chaining JBOD chassic to server ... why am I scared ? (ZFS)

[Bob Friesenhahn]

On Tue, 10 Jul 2012, Jason Usher wrote:
>
> But this scares me ...
>
> - two different power sources - so the "head unit" can lose power 
> independent of the JBOD device ... how well does that turn out ?

Most of your concerns are things which have been normal for fiber 
channel based arrays for quite a few years already.  SAS cables are 
shorter so there is a better chance that everything is on the same 
power and in the same rack.

>From my limited experience, getting everything on the same power helps 
with managing things.

> Just how well does ZFS v28 deal with these kind of situations, and 
> do I have a good reason to be awfully shy about doing this ?

I have been on zfs mailing lists for many years and few of the issues 
reported have been due to ZFS.  Usually problems are due to failing 
memory, bad cables, and SATA drives on SAS expanders.  SAS disks work 
better in large arrays.

There have been people running several hundred disks without problem.

Bob
-- 
Bob Friesenhahn
bfriesen at simple.dallas.tx.us, http://www.simplesystems.org/users/bfriesen/
GraphicsMagick Maintainer,    http://www.GraphicsMagick.org/