Minidisks
rather than specifying ALL, which no longer dumps anything from the
final cylinders except tracks that have been assigned as alternates.
Then you can execute theIBCDASDI utility to assign alternate tracks to
the defective tracks so that all cylinders become usable. Subsequently,
the new DDR utility can be used to restore minidisks from the tape,
possibly reordering them into the previously unusable cylinders.
Note: Whenever a minidisk is moved to a new location or its size ischanged, the corresponding MDISK statements in the system directory must
be revised.Only the new versions of the DDR, DIR, and FMT utilities should be
used with3340/3344 devices after alternate tracks have been assigned. In release 6 the starter system has been changed
to reserve cylinder348 for alternate track use. Therefore, the 3340 starter system can be restored to a disk that has defective tracks
(provided that alternate tracks have already been assigned byIBCDASDI) • 2314/2319 DISKS On 2314 and 2319 devices, CP and CMS (except CMS/VSAM) do not recognize
or support alternate track techniques for their own use.DOS, OS, and CMS/VSAM minidisks, however, do recognize and support alternate tracks
on these types ofDASD. The IBCDASDI service program automatically
assigns the last cylinder in any minidisk as an alternate track
cylinder.When you initialize 2314/2319 devices, you can assign all 203 cylinders for virtual machine and system use.
If a track assigned to a virtual machine minidisk area subsequently
becomes defective, you can:• Run the standalone CP Format/Allocate service program if the minidisk
is used byCP, and flag the whole cylinder containing the defective
track as permanently assigned(PERM). This prevents CP from ever
allocating that cylinder forCP paging, spooling, or temporary files. You must remember not to include this cylinder when you allocate disk
space for any virtual machine's minidisk in theVM/370 directory. • If the minidisk is used by either DOS, OS, or CMS/VSAM, reformat the
minidisk (including the defective track) with theIBCDASDI service
program. An alternate track is assigned at the end of the minidisk.• Set up the entire volume containing the defective track as an OS, DOS, or CMS/VSAM volume and format it with either IBCDASDI or IEHDASDR for OS or CMS/VSAM disks, or with the DOS Initialize Disk
utility program (INTDK) forDOS disks. Alternate tracks are assigned
in the standard manner.Labels All disks to be handled by CP (as an entity or as a combination of
logical disks) must have a label on real cylinder0, track 0, record 3.
This label identifies the physical volume toVM/370 and must be in the
formVOLlxxxxxx -- or -- CMS=xxxxxx where xxxxxx is a 6-character volume label. 100 IBM VM/370 Planning and System Generation Guide
rather than specifying ALL, which no longer dumps anything from the
final cylinders except tracks that have been assigned as alternates.
Then you can execute the
the defective tracks so that all cylinders become usable. Subsequently,
the new DDR utility can be used to restore minidisks from the tape,
possibly reordering them into the previously unusable cylinders.
Note: Whenever a minidisk is moved to a new location or its size is
be revised.
used with
to reserve cylinder
(provided that alternate tracks have already been assigned by
or support alternate track techniques for their own use.
on these types of
assigns the last cylinder in any minidisk as an alternate track
cylinder.
If a track assigned to a virtual machine minidisk area subsequently
becomes defective, you can:
is used by
track as permanently assigned
allocating that cylinder for
space for any virtual machine's minidisk in the
minidisk (including the defective track) with the
program. An alternate track is assigned at the end of the minidisk.
utility program (INTDK) for
in the standard manner.
logical disks) must have a label on real cylinder
This label identifies the physical volume to
form