Reference Guide › Command Reference › CHGMDISK Command

CHGMDISK Command

Use the CHGMDISK command to change or move a minidisk defined in a USER, IDENTITY, or SUBCONFIG directory entry. To change a permanent minidisk:

CHGMdisk entry vaddr ["Parms"] [("Options"]

Parms:

 {subpool | *}
[{size | = | *}
[{devtype | = | *}
[{volser | = | *]
[{loc | = | *}
[{mode | = | *}
[{rpw | =} 
[{wpw | =} 
[mpw | = ]]]]]]]]

Options:

[AUnit unitsize]
[FILE [filename]
[MSG | NOMSG]
[STACK [FIFO | LIFO]]
[FIFO]
[LIFO]
[BLKsize blksize]
[Format | NOFormat]
[Label [label]
[NOCOPY]
[Wait | NOWait]
[CAche | NOCAche]
[DEFOpt]
[MDC | NOMDC | RECORDMDC]
[WRKALleg | NOWORKALleg ]
[SYSCtl | DEVCtl | NOCtl]
[PAValias { vdev | vdev1-vdev2 | vdev.numdevs} ...]

Note: Options can be entered in any order.

To change a temporary minidisk:

CHGMdisk entry vaddr TDSK [ “Parms” ] [( “Options”]

Parms:

{size | = | *} [devtype | = | *]

Options:

[AUnit unitsize]
[FILE [filename]
[MSG | NOMSG]
[STACK [FIFO | LIFO] ]
[FIFO]
[LIFO]

Note: Options can be entered in any order.

To change a virtual minidisk:

CHGMdisk entry vaddr VDSK ["Parms"] ["Options"]

Parms:

 {size|=|*}
[{FB-512 | = | *}
[{volser|=|*]
[{loc|=|*}
[{mode|=|*}
[{rpw | =} [{wpw | =} [{mpw | =}]]]]]]]

Options:

[AUnit unitsize]
[FILE [filename]
[MSG | NOMSG]
[STACK [FIFO | LIFO]]
[FIFO]
[LIFO]

Note: Options can be entered in any order.

Definitions

entry

Specifies the name of the directory entry defining the minidisk to change or move. The user ID associated with the entry must be an active user ID.

vaddr

Specifies the virtual address of the minidisk to change or move.

subpool

Specifies the subpool from which to allocate this minidisk or the subpool list to search for space to allocate for the new minidisk. The default is *MNGR, which searches the list of subpools in which the directory manager for this user ID can allocate space for the first subpool with enough space.

You can replace subpool with a valid CA VM:Director subpool name or list word. If you specify a subpool name, it must be defined in the DASD CONFIG file and included in the requesting or owning manager’s list of subpools in the VMDIRECT MANAGERS file. ANYPOOL authorization overrides this restriction.

You can specify a subpool by name or by predefined list, which represents a variable list of subpools. The following predefined lists can be searched for available subpools. The first subpool in the list with enough space to accommodate the new minidisk is the one that is used:

CA VM:Director searches subpools in a list according to the order in which the MANAGER record in the VMDIRECT MANAGERS file specifies them. It does not include in the search any subpool that is defined with the EXPLICIT attribute.

TDSK

Specifies that the minidisk to change resides in the system temporary disk (T‑DISK) space. You can specify the device type of the T‑DISK in the devtype parameter. Otherwise, the default value that the DEVTYPE record specifies is used in the VMDIRECT MANAGERS file for the owning manager.

VDSK

Specifies that the minidisk to change resides in the system virtual disk (V‑disk) space. In this case, you must specify FB‑512 for the devtype parameter and * or = for both volser and loc to use the subsequent parameters.

size

Specifies the size of the minidisk, which can be interpreted differently, depending on the devtype and AUNIT command specifications. The following possibilities are evaluated in the order presented:

You cannot change the size of a non‑CMS formatted minidisk you are moving. You may therefore specify only an equal sign for the size of a non‑CMS formatted minidisk or a numeric value that is the same as its actual existing size. The actual size also becomes the default.

devtype

Specifies the device type (for example, 3380 or 3390) for the new minidisk. All device types CA VM:Director supports are valid, including those defined on the DEVTYPE record in the DASD CONFIG file.

By default, CA VM:Director determines devtype based on the location of the allocation. If you specify an equal sign, the device type remains the same as the original minidisk.

You cannot change the device type of a non‑CMS formatted minidisk you are moving. You therefore may only specify either an equal sign or the existing device type. The default also becomes the device type of the existing minidisk.

The devtype parameter is a determinant in calculating the size of the minidisk. For more information, see the description of the size parameter, above.

volser

Specifies the volume serial number (volser) of the DASD volume on which CA VM:Director is to allocate the new minidisk. The volume must be defined in the DASD CONFIG file and the subpool (specified on the subpool parameter) must be defined on one of the volume extents.

By default, CA VM:Director determines volser based on the location of the allocation. If you specify volser as an equal sign, CA VM:Director allocates the new minidisk from the same volume as the original one.

loc

Specifies the location (starting cylinder for CKD devices or block number for FBA devices) at which to allocate the new minidisk on the specified volume. Specify an integer with up to seven digits for number of cylinders or blocks.

If you specify the location, you must specify the volser parameter as a valid volume name or an equal sign. If you specify an equal sign, CA VM:Director uses the starting location of the original minidisk, presumably on a different volume but of the same device type. If the volume name is unchanged, the allocation of the new minidisk fails, because the original minidisk still occupies that space.

If you specify an equal sign for both volser and loc, size and devtype must also be the same as the original minidisk to indicate that a new minidisk is not to be allocated. You can then change any or all of the following: the label, mode, passwords, and caching attributes.

By default, CA VM:Director allocates the minidisk according to the algorithms defined for the applicable subpool.

mode

Specifies the read/write mode for the new minidisk when the user ID logs on. CP defines the valid modes, which are R, RR, W, WR, M, MR and MW, each with an optional suffix of V, S, E, VS, VE, D, VD, SD, ED, VSD, and VED. The default for mode is MR. If you specify it as an equal sign, CA VM:Director uses the link mode of the original minidisk.

You can change the mode without moving the minidisk by specifying an asterisk for the subpool and an equal sign for each of the other parameters. You can also specify the original values instead of an equal sign.

rpw wpw mpw

Specifies the new read, write, and multiple link passwords, respectively, for the minidisk. Each password can be one to eight characters in length. If you specify nothing or an equal sign for any password, that password remains unchanged. To remove an existing password, you must specify the literal ‘$NONE$’ for the password to remove and for all existing passwords following it. This literal string is a restricted keyword and should not be used for any link password.

To specify a new write password, you must specify a new read password or an equal sign. To specify a new multiple link password, you must specify new read and write passwords or equal signs.

(CA VM:Secure only) If PEF is installed, CA VM:Secure takes passwords as clear text passwords and then encrypts them.

You can change the passwords without moving the minidisk by specifying an asterisk for the subpool and an equal sign for the original values for each of the other parameters.

[AUnit unitsize]

Specifies an alternate allocation unit size CA VM:Director is to use when it calculates the size of the new minidisk. When this option is used, it interprets the value for the size parameter as the number of blocks of the size unitsize. It then uses this number to calculate the actual allocation size depending on the type of device used.

Possible values for unitsize are 512, 1024, 2048, 4096, 1K, 2K, and 4K. The default for unitsize is the specified or default value for BLKSIZE.

You cannot specify AUNIT for non‑CMS formatted minidisks.

[BLKsize blksize]

Specifies the CMS block size to use when formatting the new minidisk. Possible values for blksize are 512, 1024, 2048, 4096, 1K, 2K, and 4K. By default, CA VM:Director uses the value specified for AUNIT; if no value is specified for AUNIT, it uses the current block size of the minidisk being moved.

You cannot specify BLKSIZE for minidisks allocated to T‑DISK or for non‑CMS formatted minidisks. If you specify the NOFORMAT option, the BLKSIZE option is ignored.

[CAche | NOCAche]

Enables (CACHE) or disables (NOCACHE) minidisk caching at the control unit. CA VM:Director puts the specified option on a MINIOPT record for the new minidisk.

You can combine these options with the MDC and NOMDC options to get the desired level of caching. You cannot use these options with the DASDOPT record options SYSCTL, DEVCTL, and NOCTL.

[DEFOPT]

Establishes the default caching attributes for the minidisk. This may mean that a MINIOPT record is removed or that CA VM:Director creates a MINIOPT or DASDOPT record that reflects the desired default setting for this device type on this operating system.

You cannot specify this option with any of the MINIOPT or DASDOPT options. If you do not specify this option or any of the MINIOPT or DASDOPT options, no changes are made to existing MINIOPT or DASDOPT records.

[Format | NOFormat]

Formats (FORMAT) or does not format (NOFORMAT) the old minidisk after moving it.

CA VM:Director formats the original minidisk after the move is completed using a block size of 4K and changes the label of the original minidisk to ERASED.

You must have NOFORMAT MOVE authorization to specify NOFORMAT. CA VM:Director ignores the FORMAT and NOFORMAT options for minidisks defined on T‑DISK or V‑DISK.

[Label [ label]]

Specifies the minidisk label to give the new minidisk during formatting. The default is the label from the original minidisk.

You can change the label without moving the minidisk by using an asterisk for subpool, an equal sign for the rest of the parameters, and specifying the new value for the LABEL option. You can also specify the original values instead of an equal sign.

You cannot specify LABEL for non‑CMS formatted minidisks.

The LABEL option and the NOCOPY option are mutually exclusive.

[MDC | NOMDC | RECORDMDC]

MDC enables full track minidisk cache for the minidisk. NOMDC disables full track minidisk cache. RECORDMDC specifies that the minidisk will use record level minidisk caching.

CA VM:Director puts the specified option on a MINIOPT record for the minidisk. You cannot use these options with the DASDOPT record options SYSCTL, DEVCTL, and NOCTL.

Note: For more information about MINIOPT and DASDOPT record options, see the IBM CP Planning and Administration guide for the VM release you are running.

[NOWRKALleg | WRKALleg]

WRKALLEG causes the working allegiance to be simulated on the minidisk. NOWRKALLEG causes no simulated working allegiance for the minidisk.

CA VM:Director puts the specified option on a MINIOPT or DASDOPT record depending on what other options are specified.

[PAValias {vdev | vdev.numdevs | vdev1-vdev2}]

Defines a single virtual device (vdev) or multiple virtual devices which represent alias Parallel Access Volumes for a non-fullpack minidisk base Parallel Access Volume.

CA VM:Director puts the specified option on a MINIOPT record if specified for a permanent minidisk or on a DASDOPT record if specified for a permanent fullpack minidisk defined with DEVNO.

[NOCOPY]

Moves the minidisk as specified by all other parameters of the CHGMDISK command, but does not copy the data or format the minidisk at the original or new location. Generally, use this option during a migration when it is necessary to redefine a minidisk but not copy the data. You must have NOCOPY authorization in the AUTHORIZ CONFIG file to use this option.

The LABEL option and the NOCOPY option are mutually exclusive.

[SYSCtl | DEVCtl | NOCtl]

Specifies the kinds of I/O commands that can be issued against this minidisk:

CA VM:Director puts the specified option on a DASDOPT record for the minidisk.

Use these options only for full‑pack minidisks. They cannot be used with the MINIOPT record options CACHE, NOCACHE, MDC, NOMDC, and RECORDMDC.

Note: For more information about MINIOPT and DASDOPT record options, see the IBM CP Planning and Administration guide for the VM release you are running.

[FILE [filename]]

[MSG | NOMSG]

[STACK [FIFO | LIFO]]

[FIFO]

[LIFO]

[Wait | NOWait]

These options are explained in the Common API Command Options.

Description

The CHGMDISK command changes or moves a minidisk for an active user ID. It can also change the label, link mode, passwords, or caching attributes of a minidisk without actually moving the minidisk.

When a CA VM:Director macro calls the CHGMDISK command, it stacks a record for use by the calling macro when it successfully moves the minidisk. The stacked record is in last in, first out (LIFO) order and contains all the information necessary to build an MDISK record to describe the minidisk new location. The stacked record has the following format:

vaddr devtype start size volser linkmode rpw wpw mpw

The start and size values are in blocks for FBA and cylinders for CKD devices.

(CA VM:Secure only) If PEF is installed, passwords are encrypted.

If another CA VM:Director macro does not call CHGMDISK, it does not stack any record.

Return Codes and Error Messages

The following table lists return codes and error messages for the CHGMDISK command.

Note:

• For explanations of the message routing and disconnect options, see Common API Command Options.
• For MDISK statement parameter definitions, see ADDMDISK Command. (They are equivalent to the ADDMDISK command parameters.)
• For more information about the EXPLICIT attribute, see SUBPOOL Record.
• For more information about NOFORMAT authorizations, see the Authorizations for Command Processing table in the chapter "Authorizations" of the Administration Guide.
• For complete descriptions of all messages listed in this section, see the Message Reference Guide.