For just an operating system upgrade to a new z/VM release/version a complete install is not required. A subset of the full installation steps can be done.
To install z/VM 640 go through:
M9C0I000: Specify If New Install or Upgrade
M9C0I002: Specify Maintenance Minidisks
M9C0I005: Specify CP Installation Option
(NOTE: If installing on a system where MDISK password prompts may be issued you should make sure CAIMAINT has OPTION LNKNOPAS for the next task. Note the need to modify your CP CNTRL file to include 'CF640 AUXAV640 TXA' and 'ACF AUXACF' lines as illustrated in the help information in the top XEDIT session.)
M9C0I006: Modify CP CNTRL File
M9C0I007: IF using CMS security
M9C0I008: IF using CMS security (scroll help instructions -> DF,DB)
M9C0I010: Copy Files to Test System Disks
M9C0I013: Specify Service Machine Minidisk Links
M9C0I015: Create/Edit ACFCP CAXALOAD File (change 630 to 640 if necessary)
M9C0I017: Edit CA ACF2 for VM $PPF File
Perform Maint tasks, Process the ACF2TASK EXEC steps
2 Modify VMXAOPTS
4 Generate the CP Nucleus, IPL, and Update VMO Records
If running with CMS security continue with these steps:
5 Preliminaries for CMS installation.
6 Add intercepts to CMS and CMS/DOS modules.
7 Generate the CMS nucleus with CA-ACF2 intercepts
8 Generate module files for various CMS commands.