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 frecover(1M)							frecover(1M)




 NAME
      frecover - selectively recover files

 SYNOPSIS
      /usr/sbin/frecover -r [-hmosvyAFNOX] [-c config] [-f device] [-S skip]
	   [-E extarg]

      /usr/sbin/frecover -R path [-f device]

      /usr/sbin/frecover -x [-hmosvyAFNOX] [-c config] [-e path] [-f device]
	   [-g graph] [-i path] [-S skip] [-E extarg]

      /usr/sbin/frecover -I path [-vy] [-f device] [-c config]

      /usr/sbin/frecover -V path [-vy] [-f device] [-c config]

 DESCRIPTION
      frecover reads media written by the fbackup command.  Its actions are
      controlled by the selected function -r, -R, -x, -V, or -I.

      The function performed by frecover is specified by one of the
      following options:

      -r	  The backup media is read and the contents are loaded into
		  the directories from which they were backed up.  This
		  option should only be used to recover a complete backup
		  onto a clear directory or to recover an incremental backup
		  after a full level-zero recovery (see fbackup(1M)).  This
		  is the default behavior.

      -x	  The files identified by the -i, -e, and -g options (see
		  below) are extracted or not extracted from the backup
		  media.  If a file to be extracted matches a directory
		  whose contents have been written to the backup media, and
		  the -h option is not specified, the directory is
		  recursively extracted.  The owner, modification time, and
		  access control list (including optional entries, unless
		  the -A option is specified) are recovered.  If no file
		  argument is given (including an empty graph file), all
		  files on the backup media are extracted, unless the -h
		  option is specified.

      -I path	  The index on the current volume is extracted from the
		  backup media and is written to path.

      -V path	  The volume header on the current volume is extracted from
		  the backup media and is written to path.  The following
		  fields from the header are extracted in the format
		  label:value with one pair per line.





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		  Magic Field		      On valid fbackup media, it
					      contains the value
					      FBACKUP_LABEL.  On pre-10.20
					      fbackup media, it contains
					      FBACKUP LABEL.
		  Machine Identification      This field contains the result
					      of uname -m.
		  System Identification	      This field contains the result
					      of uname -s.
		  Release Identification      This field contains the result
					      of uname -r.
		  Node Identification	      This field contains the result
					      of uname -n.
		  User Identification	      This field contains the result
					      of cuserid(3S).
		  Record Size		      This field contains the
					      maximum length in bytes of a
					      data record.
		  Time			      This field contains the time
					      fbackup was started.
		  Media Use		      This field contains the number
					      of times the media has been
					      used for backup.
		  Volume Number		      This field contains a #
					      character followed by 3
					      digits, and identifies the
					      current volume in the backup.
		  Checkpoint Frequency	      This field contains the number
					      of data records between
					      checkpoints.
		  Fast Search Mark Frequency  This field contains the number
					      of files between fast search
					      marks for backups made with
					      DDS tape drives.
		  Index Size		      This field contains the size
					      of the index.
		  Backup Identification Tag   This field is composed of 2
					      items: the process ID (pid),
					      and the start time of that
					      process.
		  Language		      This field contains the
					      language used to make the
					      backup.

      -R path	  An interrupted full recovery can be continued using this
		  option.  frecover uses the information in file path to
		  continue the recovery from where it was interrupted.	The
		  only command line option used by frecover with this option
		  is -f.  The values in path override all other options to
		  frecover.  Note also that only full recoveries are
		  restarted with this option, because no history of include



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		  or exclude lists is stored in the restart file.  If a
		  partial recovery (i.e., using the -x option) is
		  interrupted then restarted with this option, frecover
		  continues recovering where the partial recovery left off,
		  but restores all files on the backup media beyond this
		  point.

      The following options can be used in addition to the option above that
      selects the desired function:

      -c config	  config specifies the name of a configuration file to be
		  used to alter the behavior of frecover.  The configuration
		  file allows the user to specify the action to be taken on
		  all errors, the maximum number of attempts at
		  resynchronizing on media errors (-S option), and the
		  action to be taken on media errors.  Each entry of a
		  configuration file consists of an action identifier
		  followed by a separator followed by the specified action.
		  Valid action identifiers are error, chgvol, and sync.
		  Separators can be either tabs or spaces.  In the following
		  sample configuration file, each time an error is
		  encountered, the script
		  /var/adm/fbackupfiles/frecovererror is executed.  The
		  script /var/adm/fbackupfiles/frecoverchgvol is executed
		  each time the backup media is to be changed.	The maximum
		  number of resynchronization attempts is five.

		  error	 /var/adm/fbackupfiles/frecovererror
		  chgvol /var/adm/fbackupfiles/frecoverchgvol
		  sync 5

      -e path	  path is interpreted as a graph to be excluded from the
		  recovery.  There is no limit on how many times the -e
		  option can be specified.

      -f device	  device identifies the backup device to be used instead of
		  the default /dev/rmt/0m.  If device is -, frecover reads
		  from standard input.	Thus fbackup and frecover can be
		  used in a pipeline to backup and recover a file system as
		  follows:

		  fbackup -i /usr -f - | (cd /mnt; frecover -Xrf -)

		  If more than one output file is specified, frecover uses
		  each one successively and then repeats in a cyclical
		  pattern.  Patterns can be used in the device name in a way
		  similar to file name expansion as done by sh(1).  The
		  expansion of the pattern results in all matching names
		  being in the list of devices used.  A device on the remote
		  machine can be specified in the form machine:device.
		  frecover creates a server process, /usr/sbin/rmt, on the



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		  remote machine to access the tape device.  If
		  /usr/sbin/rmt does not exist on the remote system,
		  frecover creates a server process from /etc/rmt on the
		  remote machine to access the tape device.  The pattern
		  matching capability does not apply to remote devices.
		  Only raw magnetic tapes can be remote devices.  The fast
		  search marks capability is not used when accessing remote
		  DDS devices.

      -g graph	  graph defines a graph file.  Graph files are text files
		  and contain the list of file names (graphs) to be
		  recovered or skipped.	 Files are recovered using the -i
		  option; so, for example, if the user wants to recover all
		  of /usr, the graph file contains one entry:

		  i /usr

		  It is also possible to skip files by using the -e option.
		  For example, if a user wants to recover all of /usr except
		  for the subgraph /usr/lib, the graph file contains two
		  entries:

		  i /usr
		  e /usr/lib

		  If the graph file is missing, frecover exits with an error
		  message.  An empty graph file results in recovering all
		  files on the media.

      -h	  Extract the actual directory, rather than the files that
		  it references.  This prevents hierarchical restoration of
		  complete subtrees from the backup media.

      -i path	  path is interpreted as a graph to be included in the
		  recovery.  There is no limit on how many times the -i
		  option can be specified.

      -m	  Print a message each time a file marker is encountered.
		  Using this option, frecover prints a message each time
		  either a DDS fast search mark, a filemark (EOF), or a
		  checkpoint record is read.  Although useful primarily for
		  troubleshooting, these messages can also be used to
		  reassure the user that the backup is progressing during
		  long, and otherwise silent, periods during the recovery.

      -o	  Recover the file from the backup media irrespective of
		  age.	Normally frecover does not overwrite an existing
		  file with an older version of the file.

      -s	  Attempt to optimize disk usage by not writing null blocks
		  of data to sparse files.



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      -v	  Normally frecover works silently.  Verbose option.
		  Displays the file type and name of each file processed.

      -y	  Automatically answer yes to any inquiries.

      -A	  Do not recover any optional entries in access control
		  lists (ACLs).	 Normally, all access control information,
		  including optional ACL entries, is recovered.	 This option
		  drops any optional entries and sets the permissions of the
		  recovered file to the permissions of the backed up file.
		  Use this option when recovering files backed up from a
		  system with ACLs on a system where ACLs are not present
		  (see acl(5)).

      -F	  Recover files without recovering leading directories.	 For
		  example, this option would be used if a user wants to
		  recover /usr/bin/vi, /usr/bin/sh, and /etc/passwd to a
		  local directory without creating each of the graph
		  structures.

      -E extarg	  Specifies the handling of any extent attributes backed up
		  by fbackup.  The -E option takes the following keywords as
		  arguments:

		  warn	    Issue a warning message if extent attributes
			    cannot be restored, but restore the file anyway.

		  ignore    Do not restore extent attributes.

		  force	    Issue an error message and do not restore the
			    file if extent attributes cannot be restored.

			    Extent attributes cannot be restored if the
			    files are being restored to a file system which
			    does not support extent attributes or if the
			    file system's block size is incompatible with
			    the extent attributes.  If -E is not specified,
			    extarg defaults to warn.

      -N	  (no recovery) Prevent frecover from actually recovering
		  any files onto disk, but read the backup as if it was, in
		  fact, recovering the data from the backup, producing the
		  same output that it would on a normal recovery.  This
		  option is useful for verifying backup media contents in
		  terms of validity (block checksum errors are reported),
		  and contents (a listing of files can be produced by using
		  the -N and -v options together).  Note that the listing of
		  files produced with the -N and -v options requires the
		  reading of the entire backup, but is therefore a more
		  accurate reflection of the backup's contents than the
		  index stored at the beginning of the backup (which was



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		  created at the start of the backup session, and is not
		  changed during the course of the backup).

      -O	  Use the effective uid and gid for the owner and group of
		  the recovered file instead of the values on the backup
		  media.

      -S skip	  frecover does not ask whether it should abort the recovery
		  if it gets a media error.  It tries to skip the bad block
		  or blocks and continue.  Residual or lost data is written
		  to the file named by skip.  The user can then edit this
		  file and recover otherwise irretrievable data.

      -X	  Recover files relative to the current working directory.
		  Normally frecover recovers files to their absolute path
		  name.

 EXTERNAL INFLUENCES
    Environment Variables
      LC_COLLATE determines the order in which frecover expects files to be
      stored on the backup device and the order in which file names are
      output by the -I option.

      LC_MESSAGES determines the language in which messages are displayed.

      If LC_COLLATE and LC_MESSAGES are not specified in the environment or
      are set to the empty string, the value of LANG is used as a default
      for each unspecified or empty variable.  If LANG is not specified or
      is set to the empty string, a default of "C" (see lang(5)) is used
      instead of LANG.	If any internationalization variable contains an
      invalid setting, frecover behaves as if all internationalization
      variables are set to "C".	 See environ(5).

    International Code Set Support
      Single- and multi-byte character code sets are supported.

 WARNINGS
      For incremental backups created prior to installing HP-UX Release 8.0,
      or for recoveries that do not begin with the first volume (such as
      when reading tape 3 first), it is possible for the preceding
      directories to a recoverable file to not be on the media.	 This can
      happen, for example, if the directories did not change since the last
      full backup.  If frecover encounters a file on the backup that should
      be recovered, but it has not recovered the file's parent directories
      from the backup, it prints a message stating that the recovery will
      continue with that file, and attempts to create the file's parent
      directories as needed.

      Use of frecover does not require special privileges.  However, if a
      user does not have access permission to a given file, the file is not
      recovered.



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      The fbackup index format now includes the file size in the first
      field; the previous format simply had the '#' character in that field.
      The implementation provides both forward and backward compatibility
      between the old and new index formats.  However, the file sizes are
      used in conjunction with the checkpoints to increase selective
      recovery speed on DLT devices, so recovery of an fbackup volume that
      does not have the new index format will not see that performance gain.

      When using a DDS tape written with the current release of fbackup to
      do a partial recovery, frecover attempts to use the DDS fast-search
      capability to find files on the tape more quickly.  In order to do
      this, however, frecover needs to create an in-memory copy of the
      index, and mark the files on that index which it needs to recover
      before actually reading through the tape to find the files.  This is
      done when the first index is read from the tape, and accounts for a
      period of time just after recovery is begun where the tape is inactive
      while this in-memory index is constructed.  The larger the index is,
      the longer this period lasts.

      The utility set comprised of fbackup and frecover was originally
      designed for use on systems equipped with not more than one gigabyte
      of total file system storage.  Although the utilities have no
      programming limitations that restrict users to this size, complete
      backups and recoveries of substantially larger systems can cause a
      large amount of system activity due to the amount of virtual memory
      (swap space) used to store the indices.  Users who want to use these
      utilities, but are noticing poor system-wide performance due to the
      size of the backup, are encouraged to back up their systems in
      multiple smaller sessions, rather than attempting to back up the
      entire system at one time.  However, if the entire backup must be done
      with a single session, the user may encounter an error in frecover if
      there is not enough virtual memory available.  If this happens, the
      user might consider adjusting the maxdsiz parameter or the swap space;
      both of these require a reboot.

      Note that when recovering files with access control lists, the ACL
      entries are stored on the backup as user login names.  If a login name
      cannot be found in the password file, the file is recovered without
      its ACL, and an error is printed.	 In order to fully recover files
      backed up with ACLs, the password file (/etc/passwd) must be recovered
      before attempting to recover any desired ACLs.

      Network special files are obsolete.  Therefore, frecover cannot
      restore these files.  A warning message is issued if an attempt is
      made to recover a network special file, and the file is skipped.

      Care should be taken to match the names specified by the include and
      exclude options with the names in the index on the tape.	Since the
      files are stored on the backup in lexographic order as defined by the
      LANG or LC_COLLATE environment variable, frecover uses the exact path
      names to determine when a partial recovery is complete, and when an



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      earlier tape needs to be loaded.	If a user's specification of a file
      to be recovered is misspelled, this may cause confusing messages, such
      as frecover asking for the previous volume, when volume one is
      mounted.

 DEPENDENCIES
      frecover does not support QIC-120 and QIC-150 formats on QIC devices.
      If frecover is attempted for these formats, frecover fails and the
      following message is displayed :

	   mt lu X:Read must be a multiple of 512 bytes in QIC 120 and QIC
	   150

 AUTHOR
      frecover was developed by HP.

 FILES
      /dev/rmt/0m	  Default backup device.

 SEE ALSO
      cpio(1), dump(1M), fbackup(1M), restore(1M), rmt(1M), acl(5).

































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