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volrestore(8)							volrestore(8)
Patchkit 6							   Patchkit 6



NAME

  volrestore - Restores	a complete or partial Logical Storage Manager (LSM)
  configuration

SYNOPSIS

  /usr/sbin/volrestore [-b] [-f] [-d dir] [-i] [-g diskgroup] [-v volume...]

  /usr/sbin/volrestore -l  [-d dir] [-g	diskgroup] [-v volume...]

OPTIONS

  -b  Requests the "best possible" restoration after certain types of volre-
      store failures.  This option is useful when the failure was caused by a
      missing disk or by a conflict between the	current	LSM configuration and
      the saved	LSM configuration.

  -d dir
      Specifies	the directory where the	description files you want to use are
      located.	The default directory is the directory under /usr/var/lsm/db
      with the latest timestamp.

  -f  Forces the volrestore command to execute,	after the checksum validation
      has failed. This option is used when the saved LSM configuration has
      been manually edited (for	example, to remove configuration information
      for plexes on failed disks).

  -g diskgroup
      Specifies	the disk group whose configuration you want to restore or
      display.

  -i  Specifies	an interactive restore session,	in which volrestore prompts
      before restoring each disk group.

  -l  Lists the	configuration information that was backed up using volsave.

  -v volume
      Specifies	one or more volumes whose configuration	you want to restore
      or display.

DESCRIPTION

  The volrestore command restores an LSM configuration database	that was
  backed up using the volsave command.

  The volsave command saves configuration information in a set of files,
  called a description set. Included in	the description	set is a file con-
  taining a checksum, a	magic number, the date of the file's creation, and
  the version number of	the volsave command. Before the	volrestore command
  restores the LSM configuration from the description set, it validates	the
  checksum and the magic number.

  By default, the volrestore command uses the description files	in the direc-
  tory under /usr/var/lsm/db that has the latest timestamp. If you used	the
  -d option with volsave to save the LSM configuration in a directory other
  than the default, use	the -d option to specify that directory	to volre-
  store.

  To display the latest	LSM configuration saved	in a description set, use the
  -l option. You can use the -l	and -d options together	to display any
  description set saved	in any directory.

  You can use volrestore to restore specific volumes in	a disk group and
  specific disk	groups.	The volrestore command attempts	to reimport the	disk
  group	based on configuration information on disks which belong to the	disk
  group. If the	import fails, the disk group is	re-created by reinitializing
  all disks within that	disk group and re-creating all volumes,	unassociated
  plexes, and unassociated subdisks, based on information in the volmake
  description file.

  If you specify the -i	option,	volrestore runs	in interactive mode and
  prompts you before restoring a disk group. In	ASE or clusters	configura-
  tions, this mode is the default.

  You can also restore a complete LSM configuration. In	this case, volrestore
  attempts to reenable the vold	daemon based on	all rootdg disks in the	saved
  copy of the /etc/vol/volboot file (volboot).

  If vold cannot be enabled, you are given the option of re-creating the
  rootdg disk group and	any other disk groups using the	saved LSM description
  set. The rootdg disk group is	re-created first, and vold is put in the
  enabled mode.	Then, the other	disk groups are	re-created. The	disk groups
  are re-created by first attempting to	import them based on available disks
  in that disk group.  If the import fails, the	disk group is reinitialized
  and all volumes in that disk group are also re-created based on the volmake
  description files.

  Conflicts while Restoring the	Configuration


  When volrestore executes, it can encounter conflicts in the LSM configura-
  tion.	For example, a disk may	be missing, or another volume may be using
  the same plex	name, subdisk name, or location	on a disk. Configuration con-
  flicts usually arise because the LSM configuration was changed after it was
  saved	using volsave(8).

  When volrestore finds	a conflict, it displays	error messages and the confi-
  guration of the volume, as found in the saved	LSM description	set. In	addi-
  tion,	it removes all volumes created in that disk group during the restora-
  tion.	The disk group that had	the conflict remains imported, and volrestore
  continues to restore other disk groups.

  If volrestore	fails because of a conflict, you can use the -b	option to do
  the "best possible" restoration in a disk group. You will then have to
  resolve the conflicts	and restore the	volumes	in the affected	disk group.
  You can resolve the conflicts	in two ways:

    +  Check the current configuration of the diskgroup	and make any changes
       to remove the conflict. For example, rename any plexes or subdisks
       that have duplicate names. The error messages from volrestore provide
       information on what the conflict	is.

    +  Manually	edit the volmake description file for that disk	group in the
       directory that is being used by the volrestore command.




  Failures in Restoring	the Configuration


  Restoration of volumes fails if one or more disks associated with the
  volumes are unavailable, for example due to disk failure. This can, in
  turn,	cause failure in restoring a disk group. You can use a command like
  the following	to restore the LSM configuration of a disk group:

       # volrestore -b -g diskgroup

  The volumes associated with the failed disks can then	be restored by edit-
  ing the volmake description file to remove the plexes	that use the failed
  disks. Note that editing the description file	will affect the	checksum of
  the files in the backup directory, so	you will have to override the check-
  sum validation by using the -f option. You can use the -v option to restore
  the specific volumes that had	not been restored.

  When volumes are restored using the volmake description file,	the plexes
  are created in the DISABLED EMPTY state. The volrestore command does not
  attempt to start or enable such volumes. You must use	volmend	or volume to
  set the plex states appropriately before starting the	volume.	The volre-
  store	command	warns you to check the state of	each disk associated with a
  volume before	using volmend or volume	to set plex states; to carefully find
  out which disks in the LSM configuration could have had failures since sav-
  ing the LSM configuration; and to use	volmend	or volume to mark plexes on
  those	disks to be STALE. In addition,	any plex that was detached or dis-
  abled	at any point during or after the LSM configuration was saved should
  be marked STALE.

RESTRICTIONS

  The volrestore command does not restore volumes associated with the root,
  swap,	/usr, and /var file systems. See the manual Logical Storage Manager
  for information on reencapsulating the disk partitions associated with
  these	file systems.

  The following	restrictions apply to ASE or clusters configurations:

    +  The -i and -g options are required with volrestore.

    +  LSM disk	groups can only	be restored one	at a time.

    +  Before using volrestore,	the directory with the latest LSM configura-
       tion for	a disk group across all	ASE or cluster nodes should be deter-
       mined.

FILES

  /usr/var/lsm/db
      Default directory	in which volsave creates the timestamped subdirec-
      tories with LSM description sets.

  /usr/var/lsm/db/LSM.timestamp.hostname
      Timestamped subdirectory containing LSM description sets (the header,
      voldisk.list, and	volboot	files).	Also contains subdirectories for each
      disk group, named	diskgroup.d; for example, rootdg.d.

  allvol.DF
      Description file that can	be used	by the volmake command.	There is one
      file for each disk group,	stored in the diskgroup.d subdirectory.

  voldisk.list
      A	description of the disks. This file is the output of the voldisk list
      command.

  voldg.list
      A	description of the disk	group based on information from	the voldg
      list diskgroup command. There is one file	for each disk group, stored
      in the diskgroup.d subdirectory.

  volboot
      Saved copy of the	/etc/vol/volboot file.

  header
      File containing the checksum that	volrestore validates before execut-
      ing.

SEE ALSO

  volmake(4), volsave(8), volmend(8), volmake(8), volume(8)

  Logical Storage Manager