Formatting and Allocating a System Volume
If a z/VM® system volume has the wrong format or has not been formatted, your installation can format it for system use. Your support personnel must provide you with the appropriate input.
Before you format and allocate a system volume, you may wish to use the Device Support Facilities program (ICKDSF) to inspect the DASD volume for defective tracks and to assign alternate tracks if required. For more information on using this program, see Running the Device Support Facilities Program, or refer to the Device Support Facilities User's Guide and Reference book.
Use the CPFMTXA utility or invoke ICKDSF directly to format DASD. For convenience, this section illustrates the use of the CPFMTXA utility. The responses and messages may vary slightly depending on the given scenario.
For more details on the CPFMTXA utility, see the z/VM: CP Commands and Utilities Reference.
To format and allocate a system volume using the CPFMTXA utility:
- Vary the device online and attach it to your virtual machine.
Enter:
where:vary online rdev attach rdev to * as vdev
- rdev
- is the real device number of the DASD.
- vdev
- is the virtual device number you want to assign to the device.
- * (asterisk)
- indicates that you want CP to dedicate the device to your own virtual machine.
- Run CPFMTXA. Enter:
where:cpfmtxa vdev volid
- vdev
- is the virtual device number you assigned to the DASD.
- volid
- is the volume identifier you want to assign to the volume that is mounted on this device.
Note: If ICKDSF is not on an accessed disk, formatting does not take place. - Enter the input your support personnel supplies. For example, if cylinders 0 through 200 are to be used as spooling space, cylinders 201 through 400 as paging space, and the remaining cylinders as temporary disk space, enter:
spol 0-200 page 201-400 tdsk 401-end end
For FBA type DASD page expressions rather than cylinders would be used in the above example.
- After the volume is allocated, enter:
where:detach rdev from userid attach rdev to system as volid
- rdev
- is the real device number of this DASD.
- userid
- is your user ID.
- volid
- is the volume identifier of the volume that is mounted on this device.
These commands remove the volume from your virtual machine and attach it to the system.
query system rdev
where rdev is
the real device number of the DASD you just attached to the system.
If CP's response includes the words “ATTACHED CPVOL,”
CP is using the volume. If the response includes the words “ATTACHED
SYSTEM,” however, CP is not using the volume for the CP functions
listed earlier.