On Monday, 02/04/2008 at 02:12 EST, Michael MacIsaac/Poughkeepsie/[EMAIL PROTECTED] wrote:
> A DASD's label seems to change after attaching then detaching it [snip] > Any help will be appreciated. Thanks. When you detach a dedicated volume, CP re-reads the label on the suspicion that the guest could have changed the label. Otherwise, CP only reads the label when you VARY ON the volume; a QUERY does not re-read the label. Further, CP doesn't monitor guest I/O looking for label changes - that would be a performance nightmare. (ATTACH may re-read under some circumstances.... Eric or Steve would know better than I.) Though one might wonder why now, in the 21st century, virtualization support in dasd subsystems wouldn't raise some sort of unit check when one of a list of Special Things is done to a volume. Changing the content of cyl 0 would be one of them. Guess what would be in the SENSE data? The current label. If I ran the zoo.... Alan Altmark z/VM Development IBM Endicott
