Hello Bill ,

On Mon, 23 Jul 2007, Bill Davidsen wrote:

Mr. James W. Laferriere wrote:

quoted

    Hello Andrew ,

On Tue, 17 Jul 2007, Andrew Burgess wrote:

quoted

quoted

    The 'MCE's have been ongoing for sometime .  I have replaced every 
item
in the system except the chassis & scsi backplane & power 
supply(750Watts) .
    Everything .  MB,cpu,memory,scsi controllers, ...
    These MCE's only happen when I am trying to build or bonnie++ test 
the
md3 .  It consists of (now 7+1spare) 146GB drives in the SuperMicro
SYS-6035B-8B's backplane attached to a LSI22320 .

Probably every old timer has a story about chasing a hardware problem
where changing the power supply finally fixed it. I keep spares now.

If an MCE (which means bad cpu) doesn't go away after changing the cpu
it would either have to be temperature, power or a bug in the MCE code.
What else could it be?

    Thank you for the idea of 'changing out the PS' .  So I did it a bit 
differant .  I removed the system PS from the raid backplane & dropped in a 
known good ps of proper wattage & re-tested .  But left the systems ps 
attached to only the MB & fans .
    It doesn't appear to be power load related .  I tried rebuilding my 7 
disk raid6 array & I got the same thing ,  MCE .
    Now the raid backplane is still in the air stream in front of the cpu's 
and memory slots .  So it could be a marginal cpu or memory stick .

    But here's the clincher ,  when I don't use the two drives in from of 
the PS & cpu & memory slots .  The array completes it's resync .  So I'm 
back to testing memory (again) ,  If that passes then I'll try the new 
cpu(s) route .

It does sound like a cooling problem, which does not have to imply the 
overheated parts are bad, although that may be true.

 	Fyi ,  memtest86+ @ 19 passes (~ 52hours) on 8GB of memory ,  no errors .

Could be the total number of i/o in flight, etc.

 	Hmmm ,  I didn't think of this one .

Have you tried dropping two other drives?

 	Well ,  no .  I dropped those two in front of the CPU as a test in 
working my way up the scsi backplane(BP) trying to find a point that worked & 
the last two drives in the BP just happened to be in front of the cpu/memory 
air path .  The minute I put those in the MD build tree within the usual time 
frame I get a MCE .  What I have'nt tried is what you are probably suggesting 
make sure it is the drives in the air path by putting them in the MD build and 
leaving another two out .  I'll try that as well .

Can you put in a bit more fan?

 	Nope ,  It's maxed out .  sounds like a 747 on take off as it is .
 	It's a supermicro SYS-6035B-8B if you have the time to go look at the 
specs & pics .

Read the system board and CPU temps with the "sensors" package?

 	Not yet ,  I am building the need items into the kernel now .
 	Will report back (hopefully) sometime this weekend .

 		Tia ,  JimL
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| James   W.   Laferriere | System   Techniques | Give me VMS     |
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