Re: Disk controller cache

you need to go to the DST, either from a drive or from a cd.
Try this:
remove all drives, leave only the load source and try A M mode. that
is, after cloning the load source on a good drive.
Also, you could try removing the cache battery on the 2741 and if that
doesnt work, maybe the directory card (i have never in my life touched
that card), it is a memory with button cells.
In there somewhere is the configuration info for the card and you
should be able to wipe it. Does the machine per chance have another
SCSI IOA? 2763, 2778, 2748 etc etc? you could simple replace the
controller and hope the new controller likes the disks...

Best Regards,


On Fri, Apr 20, 2012 at 1:07 PM, Jim Donoghue <jdonoghue04@xxxxxxxxx> wrote:

Why do I want to clear the cache? Because of the massive failure
yesterday. I cannot boot to DST anymore - the last 'good' SRC shown is
C1392034, then it immediately starts dumping (SRCs begin with 'D'),
tries to re-IPL, then stops with a SRC B6005121.

I had saved the contents of all the drives (backed them up, sector by
sector, using SCSI tools), so here's what I was going to attempt to
do:

1. Find a way to clear the controller cache so it doesn't crab about
the disk data being different.

2. Restore all seven disk units from the backups I made

3. Attempt to IPL again

If I can keep the darn thing running long enough to replace the
failing load source drive, maybe I can get somewhere.

The interesting thing about the failing load source drive is that the
sectors that keep going bad are the same ones I keep remapping - it's
almost like it *wants* to wipe out the 'RSVDRAID' sectors (these are
two sectors near the end of the drive, with one blank sector in
between them. They contain the serial numbers and information for each
drive in the array). Both times the drive failed, both of these
sectors were unreadable.

Oh, and no, I don't have any media to attempt a 'D' IPL from.

Jim


On 4/20/12, DrFranken <midrange@xxxxxxxxxxxx> wrote:

Boot to DST. Work with Disk Units. Work with Disk Unit Recover. Reclaim
IOA Cache Storage. Select the controller and go.

*WARNING* *WARNING* *WARNING* *WARNING* *WARNING* *WARNING* *WARNING*
*WARNING*

                             Performing this function may delete all
data on your system!

*WARNING* *WARNING* *WARNING* *WARNING* *WARNING* *WARNING* *WARNING*
*WARNING*

But since you've been editing your disk data with a Linux sector editor,
I suspect this doesn't scare you much. :-)

     - Larry "DrFranken" Bolhuis.

On 4/20/2012 9:48 AM, Jim Donoghue wrote:

How does one go about clearing the cache on a disk controller (2741)?

Thanks,

Jim

--
This is the Midrange Systems Technical Discussion (MIDRANGE-L) mailing list
To post a message email: MIDRANGE-L@xxxxxxxxxxxx
To subscribe, unsubscribe, or change list options,
visit: http://lists.midrange.com/mailman/listinfo/midrange-l
or email: MIDRANGE-L-request@xxxxxxxxxxxx
Before posting, please take a moment to review the archives
at http://archive.midrange.com/midrange-l.

--
This is the Midrange Systems Technical Discussion (MIDRANGE-L) mailing list
To post a message email: MIDRANGE-L@xxxxxxxxxxxx
To subscribe, unsubscribe, or change list options,
visit: http://lists.midrange.com/mailman/listinfo/midrange-l
or email: MIDRANGE-L-request@xxxxxxxxxxxx
Before posting, please take a moment to review the archives
at http://archive.midrange.com/midrange-l.