Dennis is correct: I meant the DRCT cyls, not the source directory disk. 
<sigh>
As Richard is not running VM:Secure on that system it does not affect his 
situation, but my previous post should be corrected for future searchers 
of this list..
Perry also pointed out offlist that he recollected that VM:Secure also 
rewrote the volser (at least in older releases).  Ouch!! 

Maybe (hopefully) someone from CA is watching the list and will report 
back regarding the problem and some of the pointed responses.  Maybe one 
day we can further update the subject on the list saying "all fixed".

Mike Walter 
Hewitt Associates






"O'Brien, Dennis L" <Dennis.L.O'[EMAIL PROTECTED]> 

Sent by: "The IBM z/VM Operating System" <IBMVM@LISTSERV.UARK.EDU>
10/30/2006 05:27 PM
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Re: Corrupted IPL Record






I think Mike meant to say that when VM:Secure starts up, it reads the 
allocation bit map of the volume that has the object directory, not the 
source directory.  The two are not necessarily on the same volume.
 

 Dennis  O'Brien 

There are 10 kinds of people in the world; those that understand binary 
and those that don't.

 

From: The IBM z/VM Operating System [mailto:[EMAIL PROTECTED] On 
Behalf Of Mike Walter
Sent: Monday, October 30, 2006 13:02
To: IBMVM@LISTSERV.UARK.EDU
Subject: Re: [IBMVM] Corrupted IPL Record


Were you running VM:Secure on that system?  Are the DRCT cylinders on that 
IPL DASD?  If so, this may help. 

When VM:Secure starts up, it reads the whole allocation bit map of the 
DASD with the source directory minidisk (usually: VMSECURE 01B0).  Each 
time VM:Secure rebuilds the object directory cylinders (msg: "VMXRXB0740I 
The dynamic REBUILD has completed.  Directory maintenance activity will 
now resume.") it completely re-writes ALL of the allocation bitmap (as it 
was when VM:Secure came up) from its cached copy, except for updates to 
the bits in the DRCT cyls. 

That bit us (excuse the pun) a couple Sunday IPLs in a row when the newly 
expanded PARM disk kept getting changed back to its old size.  The back 
end of the newly updated SYSTEM CONFIG happened to have 4K blocks 
allocated on the new cylinders.  When VM:Secure re-wrote the PARM 
allocation map size/location (begin location did not change, just the 
end), it chopped off the last half or so of the SYSTEM CONFIG.  CP happily 
came up without error because the truncation just happened to be between 
SYSTEM CONFIG statements.  To diagnose it, I wrapped SYSTEM CONFIG with 
confirmatory messages issued as it runs: 
   Say "Beginning: 'SYSTEM CONFIG' from MAINT's CF1 disk..."   
   TOLERATE_CONFIG_ERRORS NO 
... rest of statements... 
   Say "Completed: 'SYSTEM CONFIG' from MAINT's CF1 disk." 

Be careful of "TOLERATE_CONFIG_ERRORS NO".  Don't just drop it in without 
trying it live.  There are non-syntactical errors which will pass CPSYNTAX 
(everyone DOES run CPSYNTAX **EVERY TIME** after changing SYSTEM CONFIG, 
right?), but will cause an IPL error.  In our case, the missing 
'Completed' statement confirmed the suspicion.  And... explained why the 
system came up so half-configured (missing the last half or so of SYSTEM 
CONFIG). 

After reporting it to CA, they said they would update the doc, showing how 
VM:Secure can cause these sorts of problems. 

By chance, I had a conversation with the CPSYNTAX developer about an open 
PMR just last week.  I suggested some type of new statement pairs which, 
if present, must BOTH be present as the first and last non-comment records 
in SYSTEM CONFIG (and perhaps IMBED files) to diagnose just this sort of 
error.

Mike Walter 
Hewitt Associates 
Any opinions expressed herein are mine alone and do not necessarily 
represent the opinions or policies of Hewitt Associates.             






"Schuh, Richard" <[EMAIL PROTECTED]> 

Sent by: "The IBM z/VM Operating System" <IBMVM@LISTSERV.UARK.EDU> 
10/30/2006 02:32 PM 

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Corrupted IPL Record








If this shows up twice, I apologize. I first sent it 2 hours ago and it 
hasn't hit the archives as yet.


Over the weekend, we upgraded our final system to 5.2. As a part of the 
migration, we changed old PARM extents to PERM and allocated new PARM 
extents. When we tried to ipl the system, there were errors that led me to 
the conclusion that the IPL program had been corrupted. Using DDR on 
another system, I observed that record 0 0 2 had been completely wiped 
out. There were a few scattered bits that were not 0 in the first 100-200 
bytes, nothing that was any kind of pattern, and the rest of the record 
was all 0. Records 1, and 3-6 were all as they should have been. I had to 
run SALIPL to fix the IPL program. 

I am not blaming CPFMTXA ALLOCATE because I think it highly unlikely that 
it was the cause. I suspect that something else happened between the 
previous IPL and yesterday's failed attempt. Has anyone else seen this 
kind of corruption or are we, once again, unique? 

Regards,
Richard Schuh


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