VANTAGE - SVCDUMP, SAMS DADSM OBTAIN ERROR

Products

• Vantage Storage Resource Manager
• GRAPHICAL MANAGEMENT INTERFACE

Issue/Introduction

During the start of VANTAGE the following messages are displayed and an SVCDUMP is taken:

12.00.00 STC72992  VKG0400I Script Actions Scheduled,DTOCSCAN
 12.00.00 STC72992  F SAMS,NEWSCAN,DTOCS
 12.00.00 STC72992  VAN0735I Automation Script GOA      DTOCSCAN: Control returned from the Event Procedure
 12.00.00 STC72992  VAN0398I DTOC Collector Posted with Option N
 12.00.00 STC72992  VAN0393I DTOC Interval Collection Starting
 12.00.56 STC72992  VAN0591E: READ OF VTOC ON VOL=XZOS24 FAILED. RC=00000004 CVAF stat=01
 12.01.02 STC72992  VAN0591E: READ OF VTOC ON VOL=XZOS25 FAILED. RC=00000004 CVAF stat=01
 12.01.09 STC72992  VAN0591E: READ OF VTOC ON VOL=XZOS26 FAILED. RC=00000004 CVAF stat=01
 12.01.09 STC72992  VAN0591E: READ OF VTOC ON VOL=XZOS23 FAILED. RC=00000004 CVAF stat=01
 12.01.15 STC72992  VAN0591E: READ OF VTOC ON VOL=XZOS22 FAILED. RC=00000004 CVAF stat=01

Environment

Vantage

Resolution

Vantage ensures the DASD volume is online, and also verifies that the UCB contains a pointer to the VTOC.

Vantage then invokes the IBM OBTAIN service (which invokes IBM's CVAF services) to read the FMT 4 DSCB. IBM documents that these services will unconditionally invoke an SVC dump if they encounter conditions they don't like. 
After doing so, they set a return code that indicates the error, and return.

Read of VTOC on VOL=%6S Failed. %45S

Reason:

A request to read the VTOC on volume vvvvvv failed with a return code of nnn. (ttt) is variable text that interprets the meaning of the nnn value. If RC=12 (CVAF failed), the following text will also appear:

CVAF R15=xxx, CVAFSTAT=yyy

Action:

The xxx and yyy values are the error codes returned from the IBM CVAF macro.

CVAF R15=00000004, CVAFSTAT=00000004

These values mean that the volume is empty. It does not contain a single data set, not even an index to the VTOC. IBM has isolated the CVAF failure on such a volume as caused by field DS4HPCHR = x'0000000000', which they further state should never occur. When a non-indexed volume is initialized, the DS4HPCHR field (the CCHHR high water mark for an F1 DSCB) is set to the CCHHR of the first F0 DSCB following the F4 and F5 DSCBs. Hence, it is nonzero.

How the DS4HPCHR field becomes zero is not known. To circumvent the CVAF R15=00000004, CVAFSTAT=00000004 error, either re-init the volume, or allocate a data set on the volume. Either of these actions should set the DS4HPCHR field to a valid nonzero value, and the CVAF error should go away.

CVAF R15=00000xxx, CVAFSTAT=00000yyy

For xxx and yyy values other than 4, consult the appropriate IBM reference manual for the meanings of these error codes. Also check if IBM message IEC6061 was issued, and respond as needed.

Put the volume in the Include-Exclude List for Online Volumes, as a volume to be excluded, until the condition causing the error has been corrected