There is a performance hit with RAID 5...as far as the ADSM mirroring...I
have used it and needed it for a disaster and it worked just fine.




"Robinson, Cris" <Cris.Robinson AT LIBERTYMUTUAL DOT COM> on 12/07/98 11:09:32 
AM

Please respond to "ADSM: Dist Stor Manager" <ADSM-L AT VM.MARIST DOT EDU>



 To:      ADSM-L AT VM.MARIST DOT EDU

 cc:      (bcc: Chris Young/Champion)



 Subject: Re: Raid or no?







We have a RAID 5 Diskpool environment of 5 9.1GB drives.Total Diskpool
storage is 34GB
We also have RAID 1 for the Database and recovery log but soon that will
go to RAID 5 comprised of 3 9.1GB drives for 18GB allsocated to Database
and
recovery log.
I have not seen any performance issues in the Lab. I'm skeptical about
ADSM's mirroring. I don't know why,
just a gut feeling.
CR
__________________________________________________
Cris Robinson
Sr. Technical Analyst
Enterprise Storage Management / ADSM
Liberty Mutual Insurance
Portsmouth, New Hampshire
603.431.8400.54837
mailto:cris.robinson AT libertymutual DOT com

If you find yourself in a hole, stop digging!
> -----Original Message-----
> From: Adam Slesinger [SMTP:aslesinger AT US.BNSMC DOT COM]
> Sent: Monday, December 07, 1998 10:52 AM
> To:   ADSM-L AT VM.MARIST DOT EDU
> Subject:      Raid or no?
>
> Fellow Adsmers,
>
> We are starting to set up adsm and we are trying to decide whether or
> not to set up our eight 9GB drives as a raid array or whether we should
> treat them as regular disks.  The adsm consultant says that it would be
> best to put the database and log on one disk and then, through adsm,
> have it mirrored on another disk.  The remaining 6 disks would be used
> for the client data which would be migrated to tape soon after going to
> disk.  The other option is to set 7 disks in a raid array and have the
> eight as a hot spare.  I am under the impression that this option is not
> recommended by IBM but cannot be sure.  Has anyone out there had
> experiences using a raid array as a primary storage pool?  Thanks!
>
> adam