A5200 And Volume manager

[John Stoffel]

James> I have a customer who would like to utilize a Sun A5200 with 22
James> disks for an Oracle Application.  The customer would like to
James> make each 9GB drive it own volume, then mount each volume to
James> the root partition.  The SA/DBA will handle striping from
James> within Oracle.  They are not looking at utilizing any form of
James> RAID.

They are doing a really poor layout here.  If this was all they
wanted, they should have just bought a bunch of disks and more
controllers to spread out the IO load as much as possible.

It would be smarter of them to use VxVM to pre-stripe the volumes
so that oracle doesn't have to know anything at all.  This would give
them quite a bit of flexibility, without concentrating all the various
layers in one spot.

Basically, Oracle will want to put various tables, logs and indexes on
various volumes.  These volumes have varrying levels of I/O demand.
Instead of having to maintain this in oracle, which I would imagine
would be *very* annoying and error prone, you should use VxVM to build
the proper I/O style volumes and have Oracle write to them.

You can then use the VxVM performance tools to measure performance,
and if you have hot spots, you can use VxVM to move data around
without even letting Oracle know or care what's happening.  

James> The A5200 will be dual attached to an E3501.  Two internal
James> drives will be mirrored.

I guess this dual-attach is the only possible reason to use VxVM,
unless they are assigning the front half of the array to one
controller and the back half to the other controller.

They need to rethink their ideas here.

John
   John Stoffel - Senior Unix Systems Administrator - Lucent Technologies
	 stoffel@lucent.com - http://www.lucent.com - 978-952-7548
	    john.stoffel@ascend.com - http://www.acend.com