RE: System Hang - Load Source IOP Buffer Overrun.

Chris, I too have been impressed in the past with AS/400's ability to
recover from errors.  The list may recall last year when I mentioned that we
had an AS/400 with an external rack for DASD and tape which was not plugged
into the UPS but into the unprotected wall outlet.  The site suffers power
outages at least twice per month ranging from mostly the 10-30 second range,
but also all the way up to 10 minutes.  Even though the external rack loses
power, the AS/400 never missed a beat!  That was just mind-boggling!  I was
told that the system recognizes that it lost a signal and keeps retrying.
Obviously, when power is lost, all the interactive jobs die, but certainly
we had a lot of batch jobs running.  Even though I found it to be a
fascinating exercise, we did eventually hook up the external rack to the
UPS.

STILL, Chris, I think your story beats even mine!  You say your jobs picked
up right where they left off when the system froze?  How?  Didn't you have
to IPL and apply PTFs?  You must have been able to somehow recover from this
before applying PTFs?  WOW.

- Dan Bale

-----Original Message-----
From: midrange-l-admin@midrange.com
[mailto:midrange-l-admin@midrange.com]On Behalf Of Chris Bipes
Sent: Thursday, February 14, 2002 10:45 AM
To: 'midrange-l'
Subject: System Hang - Load Source IOP Buffer Overrun.


Just want to send a heads up.  Last night our system froze with the system
attention light on and SRC A600 0255.  This is a 720 running 4.4 with the
latest cume applied as well as all the group PTF's.  The SST logs showed
this to be a byte stream overrun on the IOP and lost contact with the
adapters it controls.  (Ethernet, Disk, Twinax - system console, and
communication lines.)  IBM rattled off many PTF's, all MF's.  The two we did
not have I recorded, MF27330 and MF26545.  These will require an IPL to
apply.  I recommend checking your systems and getting these PTF's on before
your system burps big.

As to attain the quality of OS400, not a single keystroke was lost.  The
system recovered before I could record the SRC's.  Every job resumed where
they left off.  What a beautiful system.

Christopher K. Bipes      mailto:ChrisB@Cross-Check.com
Operations & Network Mgr  mailto:Chris_Bipes@Yahoo.com
CrossCheck, Inc.                  http://www.cross-check.com
6119 State Farm Drive     Phone: 707 586-0551 x 1102
Rohnert Park CA  94928    Fax: 707 586-1884