RE: Spurious HD convictions

Hmm.  I don't see how it could be either the PS or the PMs, since the drives 
were moved to a new enclosure when the problem started happening, yet the 
problem persists.  The new chassis has all new PMs and of course a new PS, 
and the problem is happening across multiple PMs.  In addition, if NCQ is the 
problem, why has it just started happening?  This system has been up and 
running for the better part of a year.  Regardless, I have disabled NCQ by 
executing `echo 1 > /sys/block/sd[a-g]/device/queue_depth`, and I am 
attempting a repair action again.  We'll see how it goes.

Hi Leslie,

According to some of the links here:
http://www.google.com/search?hl=en&q=failed+to+read+SCR+1+(Emask%3D0x40)

It seem to be either the Power Supply Unit (PSU) or the Port Multiplier
(PM).

A quick workaround seem to be disabling NCQ on all affected devices.

On Sun, Dec 13, 2009 at 5:02 AM, lrhorer@satx.rr.com
[off-list ref] wrote:

quoted

       What's happening here?  Suddenly, my backup server is suffering

apparently

quoted

spurious hard drive convictions.  The server is running RAID5 on 7 disks
under md.  It has been running well for months, but suddenly it has

started

quoted

kicking drives from the array when under moderately heavy read or write
loads.  The thing is, it isn't convicting any particular drive

repeatedly,

quoted

and the drives are not showing any errors under SMART.  This is a PM

system,

quoted

and I have tried changing the drive adapters, changing the PMs, changing
cables, moving the drives around, and moving them out of the CPU

enclosure to

quoted

a new external chassis.  The convictions are not occurring on any one
channel, over any one particular PM, or over any particular cable.

 Since

quoted

this started happening, I have been unable to get all the way through a
resync before the array dumps at least one of the drives.  Here is a

sample

quoted

from the kernel log during one of the convictions: