# @(#)src/sol/cmd/vxvm/voladm/disk.menu.help	1.8.45.1 10/22/01 10:01:55 - Copyright (c) 1999 VERITAS Software Corp.
#ident "@(#)unixvm:src/sol/cmd/vxvm/voladm/disk.menu.help 1.8.45.1"

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 Operations provided in the Volume Manager disk operations menu:

  Add or initialize one or more disks

      Use this menu operation to add disks to the system. The disks
      must already have been formatted (format(1M) and have a valid
      VTOC (prtvtoc(1M)).

      You will be prompted to enter a disk device address pattern list
      which may be used to specify one or more disks. The operation
      will then prompt for a disk group name and disk name for the
      disks. A disk group name of 'none' may be specified which will
      cause the disks to be left as unassigned replacement disks. If a
      new disk group name is specified the disk group will be created
      and the disks added to the new disk group. By default disks are
      added to the root disk group, rootdg. If a disk group is
      specified for the disks, you may specify that the disks be
      designated as spares for the disk group. The disks can also be
      marked as nohotuses to be excluded from hot-relocation use.

      If a disk is found to already contain non-Volume Manager
      partitioning, you will be asked whether the disk should be
      encapsulated. Encapsulation will turn each partition of the disk
      into a volume. A disk should be encapsulated if it contains file
      systems or data that should not be overwritten. If encapsulation
      is not desired for a disk the disk can be initialized as a new
      disk for use by the Volume Manager. For new disks all space on
      the disk becomes free space in the disk's disk group. The menu
      operation interactively allows encapsulation or initialization to
      be decided for all the disks specified.

  Encapsulate one or more disks

      Use this menu operation to place under Volume Manager control one
      or more disks that were added to the system before installing the
      Volume Manager.
      
      You will be prompted to enter a disk device address pattern list
      which may be used to specify one or more disks. The operation
      will then prompt for a disk group name and disk name for the
      disks. The disk will be added to the given disk group with the
      specified disk name.  The disk will be examined in search of
      partitions that are used for file systems, or for other
      purposes.  Volumes will be created to replace disk partitions as
      the means of accessing the data.  If the encapsule operation
      cannot determine the purpose for a partition automatically, you
      will be asked what to do with it.  You can choose to replace the
      partition with a volume, keep the partition as-is, or remove the
      partition.

      You will be required to reboot the system if any partitions are
      in use for mounted file systems or for running applications.  You
      may have to modify application configuration files to use
      volumes, rather than direct disk devices, to access the disk
      partitions.  File system mount information in /etc/vfstab will
      be adjusted automatically.

  Remove a disk

      Use this menu operation to remove a disk from a disk group.  You
      will be prompted for the name of a disk to remove.  You cannot
      remove a disk if any volumes use storage on the disk.  If any
      volumes are using storage on the disk, you have the option of
      asking the Volume Manager to move that storage to other disks in
      the disk group.

      NOTE:  You cannot remove the last disk in a disk group using
             this operation.  If you wish to use all the remaining disks
             in a disk group for some purpose, you should disable
             (deport) the disk group.  You will then be able to reuse
             the disks.

  Remove a disk for replacement

      Use this menu operation to remove a physical disk from a disk
      group, while retaining the disk name.  This changes the state
      for the disk name to a "removed" disk.  If there are any
      initialized disks that are not part of a disk group, you will be
      given the option of using one of these disks as a replacement.

  Replace a failed or removed disk

      Use this menu operation to specify a replacement disk for a disk
      that you removed with the Remove a disk for replacement menu
      entry, or that failed during use.  You will be prompted for a
      disk name to replace and a disk device to use as a replacement.
      You can choose an uninitialized disk, in which case the disk
      will be initialized, or you can choose a disk that you have
      already initialized using the Add or initialize a disk menu
      operation.

  Mirror volumes on a disk

      This menu option prompts for a disk, by media name.  It then
      prompts for a destination disk within the same disk group, also
      by media name.  Specifying no destination  disks indicates that
      any disk is suitable.  The operation proceeds by calling vxmirror
      to mirror the volumes.

      Mirroring volumes from the boot disk will produce a disk that can
      be used as an alternate boot disk. This will be done by calling
      the vxrootmir command.

  Move volumes from a disk

      Use this menu operation to move any volumes that are using a
      disk onto other disks.  Use this menu immediately prior to
      removing a disk, either permanently or for replacement.

      NOTE:  Simply moving volumes off of a disk, without also removing
             the disk, does not prevent volumes from being moved onto
             the disk by future operations.  For example, using two
             consecutive move operations may move volumes from the
             second disk to the first.

  Enable access to (import) a disk group

      Use this menu operation to enable access by this system to a
      disk group.  If you wish to move a disk group from one system to
      another, you must first disable (deport) it, on the original
      system.  Then, move the disk between systems and enable (import)
      the disk group.  You will be prompted for the disk device of a
      disk containing the disk group.  All enabled (online) disks will
      be searched to locate disks that are in the same disk group as
      the given device.

  Remove access to (deport) a disk group

      Use this menu operation to disable access to a disk group that
      is currently enabled (imported) by this system.  Deport a disk
      group if you intend to move the disks in a disk group to another
      system.  Also, deport a disk group if you want to use all of the
      disks remaining in a disk group for some new purpose.

      You will be prompted for the name of a disk group.  You will
      also be asked if the disks should be disabled (offlined).  For
      removable disk devices on some systems, it is important to
      disable all access to the disk before removing the disk.

  Enable (online) a disk device

      If you move a disk from one system to another during normal
      system operation, the Volume Manager will not recognize the
      disk automatically.  Use this menu operation to tell the
      Volume Manager to scan the disk to find what disk it is, and
      to determine if this disk is part of a disk group.  Also, use
      this operation to re-enable access to a disk that was disabled
      by either the disk group deport operation or the disk device
      disable (offline) operation.

   Disable (offline) a disk device

      Use this menu operation to disable all access to a disk device
      through the Volume Manager.  This operation can be applied only
      to disks that are not currently in a disk group.  Use this
      operation if you intend to remove a disk from a system without
      rebooting.

      NOTE:  Many systems do not support disks that can be removed from
             a system during normal operation.  On such systems, the
             offline operation is seldom useful.

   Mark a disk as a spare for a disk group

      This option sets up a disk to be used as a spare device for
      its disk group. A spare disk can be used to automatically
      relocate a subdisk that has failed. No space can be used on a disk
      that is marked as a spare.

  Turn off the spare flag for a disk

      This option removes a disk from those that can be used as a
      spare and returns its space to the general pool of available
      space.

  Unrelocate subdisks back to a disk

      Use this operation to move subdisks which were hot-relocated back
      onto the original disk that has been replaced due to a disk failure. 

  Exclude a disk from hot-relocation use

      Use this option to make a disk in the free pool not available
      for hot-relocation use. The space on the disk will remain as
      free space in the disk group, only not available for use by
      hot-relocation.

  Make a disk available for hot-relocation use

      Use this option to make a disk in the free pool available
      for hot-relocation use. This only applies to disks that were
      previously excluded from hot-relocation use.

  Prevent multipathing/Suppress devices from VxVM's view

      Use this option to exclude devices from the view of VxVM or prevent
      them from being multipathed by vxdmp.

  Allow multipathing/Unsuppress devices from VxVM's view

      Use this option to re-include devices (which were earlier excluded)
      to make them visible to VxVM again or let vxdmp multipath them
      again.

  List currently suppressed/non-multipathed devices

      Use this option to list the devices that have been suppressed from
      VxVM's view or prevented from being multipathed by vxdmp.
 
  Change the disk naming scheme

      Changes the disk naming scheme from the c#t#d# format to
      enclosure-based. Alternatively, if the existing naming scheme is
      enclosure-based, it is changed to c#t#d# format.

  Get the newly connected/zoned disks in VxVM view

      This command will scan and configure any new disk devices that
      are attached to the host, disk devices that became online, or
      fibre channel devices that were zoned to host bus adapters
      connected to this host.

      This command will call operating system specific interfaces for
      configuring new hardware devices so that the Operating System
      can see them, and scan any new disks that were newly added since
      vxconfigd was last started. In this manner, disks can be dynamically
      configured to the system and then recognized by the Volume Manager
      in volume manager view.

      It should be used whenever any disks are physically connected to
      the host or when fibre channel devices are zoned to the host.

  List disk information

      Use this menu operation to display the list of disks attached
      to your system.  This will also list removed or failed disks.
      Removed and failed disks are disconnected from specific devices.
      Such disks are candidates for the Replace a failed or removed
      disk menu operation.

      You can also use this operation to list detail for a particular
      disk.  This detail includes, among other things, the disk group
      of which the disk is a member, even if that disk group is
      currently disabled.

 Glossary:

  Disk device address: a system-dependent name that defines the
      hardware address of a disk.  Disk devices for this operating
      system are defined by a controller number, a target address
      number, and a disk number, in the form:

		c<controller>t<target>d<disks>

      If you have disks attached to a SCSI disk controller, the target
      number for a disk is the target ID defined by switch settings on
      the disk, ranging from 0 to 7.  Some SCSI devices can attach
      several disks under a single target ID.  For such devices, each
      disk is assigned a different disk number, ranging from 0 to 7.

  Disk group: a collection of disks that are maintained with a common
      configuration.  Volumes are defined within a disk group, and can
      be composed only from disks in that disk group.  One disk group,
      named rootdg, is provided on all systems.  You can create
      additional disk groups, if you want.  Disk groups other than
      rootdg can be moved between two systems by disconnecting the
      disks from the first system and attaching them to the second.

  Disk name: A disk in a disk group has special identifiers stored on
      it by the Volume Manager.  These identifiers are used to
      identify a physical disk independent of its location.  A disk
      can be moved between controllers, or to different target IDs on
      a controller.  The Volume Manager will recognize that the disk
      has moved without additional intervention.

      Because disks can be moved, the Volume Manager requires a
      location-independent name, assigned by the system administrator,
      to identify a particular physical disk within a disk group.
      This name does not change if the disk is moved, even if the disk
      group is moved between two systems.

  Removed disk: A disk can be removed from a disk group temporarily,
      either with the intention of adding the same disk back to the
      disk group or of replacing the disk with a new physical disk.
      Removal for replacement is a special type of removal.
      Typically, you will remove a disk group from a disk group if the
      disk fails and you want to replace it.  If a disk is removed for
      replacement, the disk name is retained as a place-holder, which
      retains the configuration of subdisks on the disk.  When the
      disk is replaced, data for the subdisks is recovered from other
      sources, where possible.

  Failed disk: If a disk is physically removed from the system without
      telling the Volume Manager, or if a cabling failure or other
      major disk failure prevents the Volume Manager from being able
      to read the special identifiers stored on a disk, then the
      Volume Manager will not be able to match up a disk name within a
      disk group to a particular physical disk.  If this happens, the
      disk will not be usable and is considered to be "failed".
      Failed disks can be replaced, just like removed disks.  However,
      if the failure condition goes away (for example, if the cable is
      reconnected), then a reboot will handle the fix without
      additional user intervention.

  Disk partition: Disk partitioning splits a disk into pieces for
      different uses.  Partitions represent file systems, swapping
      areas, or areas for use by applications that use raw disk
      directly, such as some database products that do not use file
      systems.  Typically, the system must be rebooted to recognize
      changes made to the list of partitions on a disk.

      The Volume Manager does not use disk partitioning to split a
      disk for different uses.  Instead, the Volume Manager uses
      configuration objects called subdisks, which are a more general
      concept that can be created and removed on a running system.
      The Volume Manager slices a UNIX partition into internally-defined
      subdisks, which it dynamically creates and deletes based on user
      Volume Manager commands.
