Re: Removing (unconfigured) disks from RAID-5 array?

Hi Guys,

Apparently this question stirred up quite a lot :)

Glad to see I can stop/start parity without loosing my data...cool i5/OS feature indeed! :D

I checked the disks from DST, and it showed the following (I hope it is readable):

Parity Status:
-------------------------------------------------------------------------
Set       ASP    Unit    Type    Model    Status

1                               2782    001        RAID-5

            1            2     6718    070        Active

            *            *      6718    078        Active

            *            *      6718    078        Active

            1            1     6718    070        Active

            1            3     6718    070        Active

            1            4     6718    070        Active
-------------------------------------------------------------------------


Display Disk Config Status:
-------------------------------------------------------------------------
ASP      Unit   Serial   Type    Model    Resource Name     Status
1                                                                                   Unprotected
            1        xxxx     6718    070    DD005                    RAID-5/Active
            2        xxxx     6718    070    DD006                    RAID-5/Active
            3        xxxx     6718    070    DD003                    RAID-5/Active
            4        xxxx     6718    070    DD004                    RAID-5/Active
-------------------------------------------------------------------------

The reason for wanting to add another ASP is that they've always told me that I only should only keep identical disks in a RAID array.
I understand that, with i5/OS, I can keep a 4-disk RAID-5 array, AND a 2-disk mirror in the same ASP? Nice!

BTW the reason for the small capacity disks: my machine is a 9406 model 800...no modern SAS disks here! :)

Rene.




________________________________
From: "rob@xxxxxxxxx" <rob@xxxxxxxxx>
To: Midrange Systems Technical Discussion <midrange-l@xxxxxxxxxxxx>
Sent: Monday, August 19, 2013 8:46 PM
Subject: Re: Removing (unconfigured) disks from RAID-5 array?


Thank you.

Note: When in a dual storage IOA configuration, select performance parity
set optimization. When performance parity set optimization is specified,
the system attempts to create an even number of parity sets. An even
number of parity sets distributes the workload evenly between a pair of
adapters which are in a dual storage IOA configuration.
Note: When not in a dual storage IOA configuration, select capacity parity
set optimization or balance parity set optimization. Either of these
selections gives you the optimal capacity and balance of the parity set
configuration.

Now I just have to figure out
- whether or not I have a dual storage IOA
- when would one ever pick Availability



Rob Berendt