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Possible values of the parameter are strings in one of the following forms:

• Physical disk
  • "/dev/sd<L>" where "L" is letter.
  • "/dev/disk/by-id/..." - addressing by the disk ID, for example "/dev/disk/by-id/ata-ST1000DM003-9YN162_S1D01QJ4"
  • "/dev/disk/by-label/..." - addressing by the disk label, for example "/dev/disk/by-label/MyStorage"

  • "/dev/disk/by-uuid/..." - addressing by the disk UUID, for example "/dev/disk/by-uuid/0e808a2f-cdd3-4944-a245-f729ffd73882"
    Be careful not to destroy all the information from the disk dedicated to CHARON-AXP by mistake.
    

    Note
    "/dev/sd<L>" addressing is not persistent, so it is strongly recommended to use "/dev/disk/by-id/wwn-*" syntax instead to refer the disk by its WWID - especially in the enviroments utilizing FC and SAN storages.

     These disks must not be formatted by the host OS.

    Example:
    

    set PKA container[0]="/dev/sdb"

    It is also possible to use not a whole disk, but previously created partitions on it. In this case the syntax is the following: "/dev/sd<L><N>" where N is the number of partition to be used. 

    Example:

    set PKA container[0]="/dev/sdc1"

    .

• Multipath disk
  • "/dev/dm-<N>" 
  • "/dev/mapper/mpath<N>" 
  • "/dev/mapper/disk<N>" 
     Be careful not to destroy all the information from the disk dedicated to CHARON-AXP by mistake.  

    These disks must not be formatted by the host OS.

    Example:

    set PKA container[100]="/dev/dm-0"

    .

• Direct mapping to some SCSI device, for example, a SCSI disk or tape reader 
  

  • "/dev/sg<N>"
    Example:

    set PKA container[200]="/dev/sg0"

    .

• CD-ROM device
  • "/dev/sr<N>"
  • "/dev/cdrom" 

  • "/dev/cdrom<N>"
    Example:
    

    set PKA container[400]="/dev/sr0"

    .

• ISO file for reading distribution CD-ROM image
  • [<drive>":\"<path-name>"\"]<file-name>[".iso"]
     Mapping may also include the full path (recommended), for example: "/my_disks/vms_distributive.iso"

    Example:

    set PKA container[600]="/my_disks/vms_distributive.iso"

    .

• File representing a physical disk of the HP Alpha system (disk image)
  • [<drive>":\"<path-name>"\"]<file-name>[".vdisk"]
    These files can be created from scratch with "mkdskcmd" utility. Data and OS disk backups are transferred from the original system via tapes or network and restored into these container files.   

    Mapping may also include the full path, for example: "/my_disks/my_boot_disk.vdisk"

    Example:

    set PKA container[401]="my_dka401.vdisk"

    .

• File representing the tape (tape image)
  • [<drive>":\"<path-name>"\"]<file-name>".vtape"
    

    These files are created automatically.

    Mapping may also include a full path (recommended), for example: "/my_tapes/backup.vtape"

    Example:

    set PKA container[500]="my_mka500.vtape"

    How the Emulator Maps Guest-OS Operations to the Virtual Tape Drive

    Guest-OS operations	Emulator Action
    Open device for reading	Create a container file if none exists. open for reading and lock container file
    Open device for writing	Create a container file if necessary; open for writing and lock the container file
    Unload (eject) tape from drive	Close a container file if open and unlock it - this allows copy/move/delete operations on CHARON host

    Info

    The container file associated with a virtual tape drive can be compared to the tape cartridge used in a physical tape drive. Both store the data written to the tape device by the guest OS. The size of virtual tape container files is limited only by space available in the emulator host file system.  Prerequisite to the examples below: a virtual tape device has been configured in the CHARON configuration file and it is not in use by the guest OS. To perform backup: The tape device may be issued the "unload" command and the container-file moved/deleted to insure proper status  Initialize the tape device using standard guest OS procedure. Perform backup. Issue "unload" command to the tape device in the guest OS. On the emulator host, move the *.vtape container file containing backup data for storage or further backup. To restore from a backup: The tape device may be issued the "unload" command to insure proper status. On the emulator host, move or copy a *.vtape container file containing backup data onto the filename specified in the CHARON configuration file. Perform restore. Issue the "unload" command to the tape device in the guest OS. Delete or move the container file in preparation for the next vtape operation. Warning CHARON does not support muti-volume backup for tape images. If some mutli-volume set (in form of tape images) has to be restored it is recommended to configure several tape drives in CHARON configuration file, assign each tape image to each tape drive and use them in the following way (OpenVMS example): $ BACKUP MKA100:BACKUP.BCK,MKA200,MKA300,MKA4000/SAVE_SET DKA0:...

    
    

    .

This parameter is initially not set, thus creating NO storage elements on the controller.

This formatted string value specifies the explicit geometry of the disk storage element. This parameter is not applicable to tape storage elements.

The string format is <X>”/”<Y>[“/”<Z>] or <X>”,”<Y>[“,”<Z>][“,”<B>] where:

If this parameter is not set, CHARON-AXP will configure the geometry based on the most probable disk type.

Initially not set.

The syntax described above is applicable only to disk storage elements. If the container is a tape image, the following format is used instead:

Syntax:

where:

Example: