On Wednesday, 03/25/2009 at 02:11 EDT, Dieltiens Geert <geert.dielti...@inf.vanbreda.be> wrote: > We have been using our current DASD setup for about 5 months now, with no > problems, until a couple of days ago. We have 896 (256+256+256+128) devices on > the Escon channels, using 4 control units, which PTK shows as 3990-6. AFAIK > this should all be nicely within the IBM and EMC limits. > What puzzles me is that we do millions of IOs to all those devices, but the > problem only occurs with the IPL command in a virtual machine. Is there some > special kind of IO involved with IPL?
For a real (LPAR) IPL, yes, it is a special I/O. For virtual IPL, CP just reads the IPL records from the [real or virtual] disk, starts the I/O and loads the initial PSW. Alan Altmark z/VM Development IBM Endicott
