vgscan(1M)																vgscan(1M)

NAME

       vgscan - scan physical volumes for LVM volume groups

SYNOPSIS

       | | | vg_names...]

   Remarks
       If  the	volume group input arguments belong to a combination of volume groups version 1.0 and 2.0 or higher, the arguments may not be pro-
       cessed in the order they are listed on the command line.

DESCRIPTION

       The command is used as follows:

       1. Recovering and recreating the or file when the file has been deleted or does not match the current physical volumes.

       2. Reporting device special file lists for unconfigured volume groups.

       For recovery, will add entries for volume groups that are missing from or The command recovers volume group information by using  LVM  data
       structures  in kernel memory, and by probing all devices, searching for LVM disks.  If one or more physical volumes in the volume group has
       more than 8 paths, the command will only include 8 paths per physical volume.  Additional path(s) will not be added in the  or  file.   The
       volume  group device special file must be present for recovery to succeed.  In addition, will recover a missing volume group only if it has
       been activated at least once since the last boot or the last import, and the Volume Group ID is unique (see the section).

       Unconfigured volume groups are volume groups residing on attached storage that are missing from or and have not been  activated	since  the
       last  boot.  The command cannot recover the or entries for these volume groups.	Instead, it will print out the physical volume device spe-
       cial files for these volume groups.  Configure these volume groups using the command.  See vgimport(1M).

       The command will not update existing volume group entries in or unless the option is used.  The option can be used  to  overwrite  existing
       volume group entries in or Otherwise, or should be moved before running in order for the options to take full effect.

       In  HP-UX  11i Version 3, the Mass Storage Stack supports two naming conventions for the device special files used to identify devices (see
       intro(7) and lvm(7)).  Devices are represented as follows:

	      o Persistent device special files,

	      o Legacy device special files,

       LVM supports the use of both conventions within the same volume group.

       The command provides several options for controlling the use of legacy and persistent DSFs (device special files) during the  or  recovery.
       By default, will populate or with legacy DSFs, including alternate paths.  There is one exception:

	      For  activated volume groups that are using persistent DSFs, will populate or using persistent DSFs for those physical volumes.  The
	      and options allow the user to override this default behavior.

   Options and Arguments
       recognizes the following options and arguments:

	      Scan all paths of multipathed physical volumes.  The
			     option cannot be used in conjunction with the and options and when the legacy naming model is disabled with the  com-
			     mand (see rmsf(1M)).

	      Populate	     or  using both persistent and legacy DSFs.  Persistent DSFs will be added before legacy DSFs, so they will be used as
			     the primary path.	This option can be used to migrate a deactivated volume group using legacy DSFs to use	both  per-
			     sistent  and  legacy  DSFs.  The option cannot be used in conjunction with the and options and when the legacy naming
			     model is disabled with the command (see rmsf(1M)).

	      For the specified volume groups, force
			     to replace any existing entries in or with updated entries.  If the volume groups are missing from or they are added.
			     The option provides the following functions:(1)    Update  incorrect,	existing  entries  for activated volume groups.  For example, a volume group may have been
				    imported with only a partial set of devices.  Or, a boot volume group may have been activated with	persistent
				    DSFs, while the existing entry in or has legacy DSFs.(2)    Migrate a deactivated volume group using legacy DSFs to use persistent DSFs, or vice-versa.(3)    Add  volume group entries to the or file in the order specified on the command line.  For example, this option
				    can be used to put the boot volume group first in the or file.

			     With the option, will not search for additional volume groups and will not report unconfigured volume groups.

	      Skip the disk probe portion of
			     and retrieve volume group information only from LVM data structures in kernel memory.  The disk probe portion can	be
			     a time consuming operation, so this option can be used for faster recovery of or However, with this option, only vol-
			     ume groups currently activated are added to or For deactivated volume groups, no  information  is	added  to  or  The
			     option cannot be used in conjunction with the and options.

	      Populate	     or using persistent DSFs, with the following exception:

			     If  there	are  volume groups activated that are using legacy DSFs, then will populate or using legacy DSFs for those
			     physical volumes.

			     The option cannot be used in conjunction with the and options.

	      Preview the actions that would be taken but do not update
			     or This option is best used in conjunction with the option.  As with other options, if the legacy	naming	model  has
			     been disabled with the command (see rmsf(1M)), the option should also be used with the option.

	      Print verbose messages.

EXTERNAL INFLUENCES

   Environment Variables
       determines the language in which messages are displayed.

       If is not specified or is null, it defaults to "C" (see lang(5)).

       If any internationalization variable contains an invalid setting, all internationalization variables default to "C" (see environ(5)).

EXAMPLES

       1. Append  entries  for	volume	groups missing from the or file.  For deactivated volume groups, use legacy DSFs, and for activated volume
	  groups, use the DSFs that were used to activate them.  Report all physical volume legacy DSFs belonging to unconfigured  volume  groups.
	  Do not modify existing volume group entries in or Run without any options:

       2. Recreate the or file for volume groups activated since the last boot.  For deactivated volume groups, use legacy DSFs, and for activated
	  volume groups, use the DSFs that were used to activate them.	Report all physical volume legacy DSFs belonging  to  unconfigured  volume
	  groups.

		 or

       3. Recreate the or file for volume groups activated since the last boot.  For deactivated volume groups, use persistent DSFs, and for acti-
	  vated volume groups, use the DSFs that were used to activate them.  Report all physical volume persistent DSFs belonging to unconfigured
	  volume groups.

		 or

       4. Recreate  the or file for volume groups activated since the last boot.  For activated and deactivated volume groups, use both persistent
	  and legacy DSFs.  Report all physical volume persistent and legacy DSFs belonging to unconfigured volume groups.

		 or

       5. Recreate the or file for activated volume groups, using the DSFs that were used to activate them.  For  deactivated  volume  groups,	no
	  entries are added to or and no physical volume DSFs are reported.

		 or

       6. For  the volume group overwrite the existing physical volume DSFs in or with the physical volume persistent DSFs found belonging to dur-
	  ing a hardware probing of all devices.

       7. For the volume group overwrite the existing physical volume DSFs in or with the physical volume DSFs used in kernel memory.  The  volume
	  group must be activated, or this command will fail.

       8. Recreate  the  or  file  with  the volume groups and The volume group entries will be added to or in that order.  For deactivated volume
	  groups, use legacy DSFs, and for activated volume groups, use the DSFs that were used to activate them.  Do not  add	any  other  volume
	  groups.

		 or

       To preview the output for any of the above examples, include the and options in the command lines.

WARNINGS

       The option may become obsolete in future releases.

       The option may become obsolete in future releases.

       For  deactivated  volume  groups,  cannot recover volume groups that do not have a unique Volume Group ID, that is, when two or more volume
       groups share the same ID.  If this scenario occurs, the command must be used to assign a unique Volume Group ID for each volume group.  See
       vgchgid(1M).

       After  running the number and order of physical volumes in the reconstructed or file could be different than what was configured previously
       (even if the option is used).  The results could be as follows:

	      The designated primary and alternate paths may not be the same as was configured before.

	      Alternate paths will be added to the or file even though they weren't initially configured in the volume group.

	      The boot information may be incorrect, due to changed order of device special files in the new or file.

       Rectify the above problems as follows:

	      Run to activate all deactivated volume groups.  For shared volume groups, invoke to activate the shared volume  group  in  exclusive
	      mode.

	      Invoke to remove any unwanted alternate paths which were added to the or file as a result of the invocation.

	      For boot volume groups only, invoke to correct the boot information on the physical volumes.

	      If  the  original  primary path of a physical volume is now configured as an alternate, the order can be reversed by using to remove
	      the primary path and then invoking to add it back.

       The command will also print the following warning messages to notify the user of the above problems:

       No more than 8 paths to any Physical Volume will be added to the or file. All other paths will be omitted.

SEE ALSO

       lvlnboot(1M), vgchange(1M), vgcreate(1M), vgextend(1M), vgexport(1M), vgimport(1M), vgreduce(1M), intro(7), lvm(7).

																	vgscan(1M)