mkdskcmd

Description

The "mkdskcmd" utility:

Creates empty disk images of a given standard disk type or a custom disk size
Transfers existing disk images of one type to disk images of another type.

Creating disk images

The first step is to obtain the name of the disk that needs to be created:

$ mkdskcmd --list

This command results in a list of all supported disk types.

Choose the desired disk (for example "RZ22"), then use the "mkdskcmd" command to create the virtual disk image as shown below:

$ mkdskcmd --disk rz22 --output rz22.vdisk

A disk container "rz22.vdisk" will be created in the current directory.

A file "rz22.avdisk" will also be created. This file helps CHARON accurately recognize a specific disk image type. It is recommended to put the ".avdisk" file in the same directory as the created disk image.

It is also possible to create custom disk images using "--blcount" (blocks count) and "--blsize" (blocks size) switches.

To get all the available parameters please use the "–help"switch:

mkdisk for CHARON utility v. 1.14
Copyright: STROMASYS, 2015

Usage:
mkdskcmd [Options]

Options:
--help - to see help screen
-h - to see help screen

--output <full name> - to specify output file name
-o <full name> - to specify output file name

--disk <disk name> - to specify the disk name from Disk table
-d <disk name> - to specify the disk name from Disk table

--blsize <number> - to specify the block size in bytes (custom disk image)
-z <number> - to specify the block size in bytes (custom disk image)

--blcount <number> - to specify number of the blocks (custom disk image)
-c <number> - to specify number of the blocks (custom disk image)

--avtable <full_name> - to specify AVDISK table file
-a <full_name> - to specify AVDISK table file

-t - please see the '--transform' options description
--transform <source_disk_name> <source_disk_params> - to transform the the disk image (change actual size)
<source_disk_name> - the file name of the disk image to be transformed
<source_disk_params> - the name of the disk from the list of available at the Disk table
The source disk size will changed accordingly the reach the specified parameters.
To specify the transform parameters manually, follow the option below:
--transform <source_disk_name> --blsize <number> --blcount <number>

--shrink - parameter which needs to be EXPLICITLY provided, if the disk size is to be decreased
-k - parameter which needs to be EXPLICITLY provided, if the disk size is to be decreased

--list <full_name> - to display AVDISK table
-l <full_name> - to display AVDISK table

--silent - silent mode running
-s - silent mode running

Return value:
0 - for Success
Non zero - in case of failure

Examples:
mkdskcmd -h
mkdskcmd -l
mkdskcmd -a /opt/charon/bin/mkdsk.vtable -o /etc/rk07.vdisk -d rk07
mkdskcmd -o /etc/custom.vdisk -z 512 -c 16384
mkdskcmd -t /etc/rz22.vdisk rz25 -a /opt/charon/bin/mkdsk.vtable
mkdskcmd -t /etc/rz22.vdisk rz25 -a /opt/charon/bin/mkdsk.vtable -z 512 -c 262134

The "--avtable" parameter is used to work with an alternative disk specification database (or to point to the standard database ("mkdsk.vtable") if it is in a location other than the current directory).

The "--blcount" (blocks count) and "--blsize" (blocks size) switches are used to create custom disk images.

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Transferring disk images

The "mkdskcmd" utility is able to transfer (copy) disk images of one type to a disk image of another type.

This operation is needed, for example, to obtain more free space on a disk image that already contains data.

Note: it is not possible to add more free space dynamically. The virtual machine must be stopped before performing this operation.

If a source disk image is larger than the target disk image, the extra data is lost. If the source disk image is smaller, it will be extended and padded with null bytes ('\0').

An example of the syntax follows:

$ mkdskcmd --transfer <source disk file name> <source disk parameters> [--shrink] [-k]

where:

<source disk file name> - a file name of the disk image to be transferred
<source disk parameters> - the name of the disk from the list provided by the "mkdskcmd --list" command execution or the disk geometry specification (see below).
--shrink or -k - used in the case where the target disk is transferred to a smaller disk.

Example:

$ mkdskcmd --transfer /etc/rz22.vdisk rz25

It is also possible to specify the disk parameters manually with "--blcount / -c" (blocks count) and "--blsize / -z" (blocks size) switches:

$ mkdskcmd --transfer <source disk file name> -blsize <number> -blcount <number>

Example:

$ mkdskcmd -t /etc/custom.vdisk -z 512 -c 262134

There is a certain delay between the moment when the utility reports that a disk image has been transferred and its actual availability to CHARON. This delay can reach to several minutes in case of very big disks transfers. It happens because the host operating systems needs some time for actual allocation of the enlarged file on HDD.

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