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
Vantage
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