Hello Franz Josef, >normally not change. So I can copy the zvm system (res spl pag) to other
>previously reserved dasds and start zVM from there in second level. Then You don't even need the page dasd. Just page to a temp disk attached to t he VM guest. > >Of course the major prereq is that you don't have any user data on the >zvmres. The same thing I do in principle with zVSE DOSRES and SYSWK1 >too. This way I have always a fall back when there are problems after >system changes. > In fact we do, even DISKACNT and EREP are not on RES. When we migrate a V M, ie zvm520 to 540, we build new res and spl DASD. Then these DASDs are cop ied to the production VM DASD ranges and we can IPL from the new DASD. The sa me we also use for VSE. And indeed, fallback just requires to IPL from the o ld DASD. But I also want a process that can be used when only a few members are changed. Then I only have to distribute a few members instead of a full V M system. This update is somewhat easier since only a few disks are to be updated. It all depends on the amount of changes. Even more so when CP is not touched. For instance, a PTF on PTK could only require the coding (5VMPTK40 201) and perhaps the helpdisk (MAINT 19D) to be updated. No IPL required in that case. In this case, there are 8 minidisks that need to be changed, not counting OSASF and HCD. On most of them only a few CMS members are changed. So her e we update the members (a few minutes) and SHUTDOWN REIPL (one minute). A lot quicker than rebuild the VM and IPL from a different DASD. Regards, Berry.
