RE: Mirroring on i5/OS

Hi Pete

No you don't need to add the disks - you just need to have two appropriate
unconfigured disks available when you start mirroring. The system will
"find" any required disk(s) to match the ones you start mirroring on.

At some stage the machine will go dead (and perhaps give you a heart
attack!) as it does an IPL to synch the mirrored data during the start
mirroring process.

Regards
Evan Harris

-----Original Message-----
From: midrange-l-bounces@xxxxxxxxxxxx
[mailto:midrange-l-bounces@xxxxxxxxxxxx] On Behalf Of Pete Helgren
Sent: Thursday, 13 November 2008 9:39 a.m.
To: Midrange Systems Technical Discussion
Subject: Re: Mirroring on i5/OS

What is throwing me is whether I need to add the non-configured disks to
the pool first and then implement the mirroring or start mirroring and
indicate that I want the non-configured units to be the mirrors. Seems
like a chicken or egg thing: If I add the non-configured units to the
asp, they won't be available to be the mirrored pair (I think).

With raid 5 you just add the units to the asp and tell it to start RAID
protection and it all seems to work. With mirroring, I not sure how to
tell the configuration tool that the non-configured units are the ones I
want to be mirrors. Even in iSeries Navigator, it isn't clear. I guess
I'll try adding the non-configured units and then see if I can start
mirroring after they are added to the pool.

Otherwise, I'll try Pete's approach and see what my options are at IPL time.

Thanks

Pete


Wayne McAlpine wrote:

I believe you can also do it from iseries Navigator. Click on
Disks-->Disk Pools-->right click on the pool to mirror and take the
option to start mirroring.

Pete Massiello wrote:

Pete,

Try booting up in Manual mode and go into DST and WORK WITH DISK
Configuration. From there you will see what you need.

Pete

Pete Massiello
iTech Solutions
http://www.itechsol.com

-----Original Message-----
From: midrange-l-bounces@xxxxxxxxxxxx
[mailto:midrange-l-bounces@xxxxxxxxxxxx] On Behalf Of Pete Helgren
Sent: Wednesday, November 12, 2008 1:52 PM
To: Midrange Systems Technical Discussion
Subject: Mirroring on i5/OS

I thought this would be easy but I must be a little slow this week...

I have my JS12 configured with 4 drives allocated to i5/OS (More
accurately I have VIOS allocating 4 drives to the JS12 from the 6
available in the BCS). Two of which I have configured as part of
ASP1. All is well. However, I'd like to get some protection on these
drives and my understanding was that mirroring is my only option. So,
how to I achieve that ? Disk hardware status shows this:

Serial Resource Hardware
ASP Unit Number Type Model Name Status
1 1 YWEB5KZWKZRX 6B22 050 DD004 Operational
1 2 Y9EJAR7L8YMZ 6B22 050 DD003 Operational
Y384SV9UX3VE 6B22 050 DD001 Operational
YJA2X8PBPAUR 6B22 050 DD002 Operational

So, as far as I understand it, the two drives that are unallocated could
be used to mirror the other drives but I don't see any option in SST to
use these drives in a mirrored arrangement. Work with Device Parity
protection show the following menu:

1. Display disk configuration
2. Include unit in device parity protection
3. Start device parity protection - RAID 5
4. Start device parity protection - RAID 6
5. Start device parity protection - RAID 5 with hot spare
6. Start device parity protection - RAID 6 with hot spare
7. Select parity optimization

No mention of mirroring.....

So, how do I mirror these things? I get plenty of hits on mirroring
"Concepts" in the infocenter but precious little about implementation.
Running IBM i 6.1 on a JS12.

Pete