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 fbackup(1M)							 fbackup(1M)




 NAME
      fbackup - selectively back up files

 SYNOPSIS
      /usr/sbin/fbackup -f device [-f device] ...  [-0-9] [-nsuvyAEl]
	   [-i path] [-e path] [-g graph] [-d path] [-I path] [-V path]
	   [-c config]

      /usr/sbin/fbackup -f device [-f device] ...  [-R restart] [-nsuvyAEl]
	   [-d path] [-I path] [-V path] [-c config]

 DESCRIPTION
      fbackup combines features of dump and ftio to provide a flexible,
      high-speed file system backup mechanism (see dump(1M) and ftio(1)).
      fbackup selectively transfers files to an output device.	For each
      file transferred, the file's contents and all the relevant information
      necessary to restore it to an equivalent state are copied to the
      output device.  The output device can be a raw magnetic tape drive
      (for example, a DLT tape drive), the standard output, a rewritable
      magneto-optical disk, or a file.

      The selection of files to back up is done by explicitly specifying
      trees of files to be included or excluded from an fbackup session.
      The user can construct an arbitrary graph of files by using the -i or
      -e options on the command line, or by using the -g option with a graph
      file.  For backups being done on a regular basis, the -g option
      provides an easier interface for controlling the backup graph.
      fbackup selects files in this graph, and attempts to transfer them to
      the output device.  The selectivity depends on the mode (full or
      incremental) in which fbackup is being used.

      When doing full backups, all files in the graph are selected.  When
      doing incremental backups, only files in the graph that have been
      modified since a previous backup of that graph are selected.  If an
      incremental backup is being done at level 4 and the -g option is used,
      the database file is searched for the most recent previous backup at
      levels 0-3.  If a file's modification time is before the time when the
      last appropriate session began and the i-node change time is before
      the time that same session ended, the file is not backed up.  All
      directories lying on the path to a file that qualifies for the
      incremental backup will also be on the backup media, even if the
      directories do not qualify on their own status.

      If fbackup is used for incremental backups, a database of past backups
      must be kept.  fbackup maintains this data in the text file
      /var/adm/fbackupfiles/dates, by default.	Note that the directory
      /var/adm/fbackupfiles must be created prior to the first time fbackup
      is used for incremental backups.	The -d option can be used to specify
      an alternate database file.  The user can specify to update this file
      when an fbackup session completes successfully.  Entries for each
      session are recorded on separate pairs of lines.	The following four



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 fbackup(1M)							 fbackup(1M)




      items appear on the first line of each pair: the graph file name,
      backup level, starting time, and ending time (both in time(2) format).
      The second line of each pair contains the same two times, but in
      strftime(3C) format.  These lines contain the local equivalent of
      STARTED:, the start time, the local equivalent of ENDED:, and the
      ending time.  These second lines serve only to make the dates file
      more readable; fbackup does not use them.	 All fields are separated by
      white space.  Graph file names are compared character-by-character
      when checking the previous-backup database file to ascertain when a
      previous session was run for that graph.	Caution must be exercised to
      ensure that, for example, graph and ./graph are not used to specify
      the same graph file because fbackup treats them as two different graph
      files.

      The general structure of an fbackup volume is the same, no matter what
      type of device is used.  There are some small specific differences due
      to differing capabilities of devices.  The general structure is as
      follows:

	   +  reserved space for ASCII tape label (1024 bytes)
	   +  fbackup volume header (2048 bytes)
	   +  session index (size in field of volume header)
	   +  data

      Each file entry in the index contains the file size, the volume number
      and the pathname of the file.  At the beginning of every volume,
      fbackup assumes that all files not already backed up will fit on that
      volume, an erroneous assumption for all but the last volume.  Indices
      are accurate only for the previous volumes in the same set.  Hence,
      the index on the last volume may indicate that a file resides on that
      volume, but it may not have actually been backed up (for example, if
      it was removed after the index was created, but before fbackup
      attempted to back it up).	 The only index guaranteed to be correct in
      all cases is the on-line index (-I option), which is produced after
      the last volume has been written.

      Specific differences in the structure of fbackup volumes are listed
      below:

	   +  When using magnetic tape devices, the main blocks of
	      information (tape label, volume header, index, data) are
	      separated by EOF marks.  fbackup also checkpoints the media
	      periodically to enhance error recovery.  If a write error is
	      detected, the user normally has two options: (1) a new volume
	      can be mounted and that volume rewritten from the beginning;
	      or, (2) if the volume is not too severely damaged, the good
	      data before the error can be saved, and the write error is
	      treated as a normal end-of-media condition.  The blocks of
	      data with their checkpoint records are also separated by EOF
	      marks.  In addition, for DDS tape drives, if fast search marks
	      are supported, these will be used to enhance selective



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 fbackup(1M)							 fbackup(1M)




	      recovery speed by placing them between blocks of files.
	      Similarly on DLT tape drives, faster selective recovery is
	      achieved using the EOF marks used for checkpointing in
	      conjunction with the file sizes given in the index.

	   +  For a magneto-optical device, a disk, a file, or standard
	      output, there are no special marks separating the information
	      pieces; the backup is always a single file (volume).

      fbackup provides the ability to use UCB-mode tape drives.	 This makes
      it possible to overlap the tape rewind times if two or more tape
      drives are connected to the system.

    Set-up
      There are several things the user will want to consider when setting
      up fbackup for regular use.  These include type of device and media,
      full versus incremental frequency, amount of logging information to
      keep on-line, structure of the graph file, and on-line versus off-line
      backup.

      The type of device used for backups can affect such things as media
      expenses, ability to do unattended backups, and speed of the backup.
      Using 36-track tapes will probably result in the highest performance,
      but require user intervention for changing tapes.	 Both DLT and DDS
      autochangers and libraries can provide unattended backups.  A
      magneto-optical autochanger can also provide an unattended backup for
      a large system and long life media, however the media cost is high.
      Lower cost and good performance can be achieved with a single DLT tape
      drive, but multi-volume backups must be attended.

      It is also important to consider how often full backups should be
      made, and how many incremental backups to make between full backups.
      Time periods can be used, such as a full backup every Friday and
      incrementals on all other days.  Media capacities can be used if
      incremental backups need to run unattended.  The availability of
      personnel to change media can also be an important factor as well as
      the length of time needed for the backup.	 Other factors may affect
      the need for full and incremental backup combinations such as
      contractual or legal requirements.

      If backup information (output from the -V or -I options) is kept on-
      line, the required storage space must also be considered.	 Index file
      sizes are hard to predict in advance because they depend on system
      configuration.  Each volume header file takes less than 1536 bytes.
      Of course the more information that is kept on-line, the faster
      locating a backup media for a recovery will be.

      There are several ways to structure the graph file or files used in a
      system backup.  The first decision involves whether to use one or more
      than one graph file for the backup.  Using one file is simpler, but
      less flexible.  Using two or more graph files simplifies splitting



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 fbackup(1M)							 fbackup(1M)




      backups into logical sets.  For example, one graph file can be used
      for system disks where changes tend to be less frequent, and another
      graph file for the users area.  Thus two different policies can be
      implemented for full and incremental backups.

      fbackup was designed to allow backups while the system is in use by
      providing the capability to retry an active file.	 When absolute
      consistency on a full backup is important, the system should probably
      be in single-user mode.  However, incremental backups can be made
      while the system is in normal use, thus improving system up-time.

    Options
      -c config	     config is the name of the configuration file, and can
		     contain values for the following parameters:

			+  Number of 1024-byte blocks per record.
			+  Number of records of shared memory to allocate.
			+  Number of records between checkpoints.  Since the
			   EOF marks between checkpoints are also used for
			   fast searching on DLT tape drives, changing the
			   checkpoint frequency may also affect selective
			   recovery speed (see WARNINGS section).
			+  Number of file-reader processes.
			+  Maximum number of times fbackup is to retry an
			   active file.
			+  Maximum number of bytes of media to use while
			   retrying the backup of an active file.
			+  Maximum number of times a magnetic tape volume
			   can be used.
			+  Name of a file to be executed when a volume
			   change occurs.  This file must exist and be
			   executable.
			+  Name of a file to be executed when a fatal error
			   occurs.  This file must exist and be executable.
			+  The number of files between the fast search marks
			   on DDS tapes.  The cost of these marks are
			   negligible in terms of space on the DDS tape.
			   Not all DDS tape devices support fast search
			   marks.

		     Each entry in the configuration file consists of one
		     line of text in the following format: identifier, white
		     space, argument.  In the following sample configuration
		     file, the number of blocks per record is set to 16; the
		     number of shared memory records is set to 16; the
		     checkpoint frequency is set to 256; the number of file
		     reader processes is set to 2; the maximum number of
		     retries of an active file is set to 5; the maximum
		     retry space for active files is set to 5,000,000 bytes;
		     the maximum number of times a magnetic tape volume can
		     be used is set to 100; the file to be executed at



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 fbackup(1M)							 fbackup(1M)




		     volume change time is /var/adm/fbackupfiles/chgvol; the
		     file to be executed when a fatal error occurs is
		     /var/adm/fbackupfiles/error; and the number of files
		     between fast search marks on DDS tapes is set to 200.

			  blocksperrecord   16
			  records	    16
			  checkpointfreq    256
			  readerprocesses   2 (maximum of 6)
			  maxretries	    5
			  retrylimit	    5000000
			  maxvoluses	    100
			  chgvol	    /var/adm/fbackupfiles/chgvol
			  error		    /var/adm/fbackupfiles/error
			  filesperfsm	    200

		     Each value listed is also the default value, except
		     chgvol and error, which default to null values.

      -d path	     This specifies a path to a database for use with
		     incremental backups.  It overrides the default database
		     file /var/adm/fbackupfiles/dates.

      -e path	     path specifies a tree to be excluded from the backup
		     graph.  This tree must be a subtree of part of the
		     backup graph.  Otherwise, specifying it will not
		     exclude any files from the graph.	There is no limit on
		     how many times the -e option can be specified.

      -f device	     device specifies the name of an output file.  If the
		     name of the file is -, fbackup writes to the standard
		     output.  There is no default output file; at least one
		     must be specified.	 If more than one output file is
		     specified, fbackup uses each one successively and then
		     repeats in a cyclical pattern.  Patterns can be used in
		     the device name in a manner resembling file name
		     expansion as done by the shell (see sh-bourne(1) and
		     other shell manual entries).  The patterns must be
		     protected from expansion by the shell by quoting them.
		     The expansion of the pattern results in all matching
		     names being in the list of devices used.

		     There is slightly different behavior if remote devices
		     are used.	A device on the remote machine can be
		     specified in the form machine:device.  fbackup creates
		     a server process from /usr/sbin/rmt on the remote
		     machine to access the tape device.	 If /usr/sbin/rmt
		     does not exist on the remote system, fbackup creates a
		     server process from /etc/rmt on the remote machine to
		     access the tape device.  Only magnetic tapes can be
		     remote devices.  When remote DDS tape devices are used,



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 fbackup(1M)							 fbackup(1M)




		     the fast search marks capability is not used.

      -g graph	     graph defines the graph file.  The graph file is a text
		     file containing the list of file names of trees to be
		     included or excluded from the backup graph.  These
		     trees are interpreted in the same manner as when they
		     are specified with the -i and -e options.	Graph file
		     entries consist of a line beginning with either i or e,
		     followed by white space, and then the path name of a
		     tree.  Lines not beginning with i or e are treated as
		     an error.	There is no default graph file.	 For
		     example, to back up all of /usr except for the subtree
		     /usr/lib, a file could be created with the following
		     two records:

			  i /usr
			  e /usr/lib

      -i path	     path specifies a tree to be included in the backup
		     graph.  There is no limit on how many times the -i
		     option can be specified.

      -n	     Cross NFS mount points.  By default, fbackup does not
		     cross NFS mount points, regardless of paths specified
		     by the -i or -g options.

      -l	     Includes LOFS files specified by the backup graph.	 By
		     default, fbackup does not cross LOFS mount points.	 If
		     -l is specified, and the backup graph includes files
		     which are also in an LOFS directory that is in the
		     backup graph, then those files will be backed up twice.

      -s	     Back up the object that a symbolic link refers to.	 The
		     default behavior is to back up the symbolic link.

      -u	     Update the database of past backups so that it contains
		     the backup level, the time of the beginning and end of
		     the session, and the graph file used for this fbackup
		     session.  For this update to take place, the following
		     conditions must exist: Neither the -i nor the -e option
		     can be used; the -g option must be specified exactly
		     once (see below); the fbackup must complete
		     successfully.

      -v	     Run in verbose mode.  Generates status messages that
		     are otherwise not seen.

      -y	     Automatically answer yes to any inquiries.

      -A	     Do not back up optional entries of access control lists
		     (ACLs) for files.	Normally, all mode information is



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		     backed up including the optional ACL entries.  With the
		     -A option, the summary mode information (as returned by
		     stat()) is backed up.  Use this option when backing up
		     files from a system that contains ACLs to be recovered
		     on a system that does not understand ACLs (see acl(5)).

      -E	     Do not back up extent attributes.	Normally, all extent
		     attributes that have been set are included with the
		     file.  This option only applies to file systems which
		     support extent attributes.

      -I path	     path specifies the name of the on-line index file to be
		     generated.	 It consists of one line for each file
		     backed up during the session.  Each line contains the
		     file size, the volume number on which that file
		     resides, and the file name.  If the -I option is
		     omitted, no index file is generated.

      -V path	     The volume header information is written to path at the
		     end of a successful fbackup session.  The following
		     fields from the header are written in the format
		     label:value with one pair per line.

		     Magic Field	    On a valid fbackup media it
					    contains the value FBACKUP_LABEL
					    (HP-UX release 10.20 and
					    beyond).  Before HP-UX release
					    10.20, it contained the value
					    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() (see cuserid(3S)).
		     Record Size	    This field contains the maximum
					    length in bytes of a data
					    record.
		     Time		    This field contains the clock
					    time when fbackup was started.
		     Media Use		    This field contains the number
					    of times the media has been used
					    for backup.	 Since the
					    information is actually on the
					    media, this field will always
					    contain the value 0.




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 fbackup(1M)							 fbackup(1M)




		     Volume Number	    This field contains a #
					    character followed by 3 digits,
					    and identifies the number of
					    volumes in the backup.
		     Checkpoint Frequency   This field contains the number
					    of data records between
					    checkpoints.
		     Index Size		    This field contains the size of
					    the index.
		     Backup Identification Tag
					    This field is composed of two
					    items: the process ID (pid) and
					    the start time of that process.
		     Language		    This field contains the language
					    used to make the backup.

      -R restart     Restart an fbackup session from where it was previously
		     interrupted.  The restart file contains all the
		     information necessary to restart the interrupted
		     session.  None of the -[ieg0-9] options can be used
		     together with the restart option.

      -0-9	     This single-digit number is the backup level.  Level 0
		     indicates a full backup.  Higher levels are generally
		     used to perform incremental backups.  When doing an
		     incremental backup of a particular graph at a
		     particular level, the database of past backups is
		     searched to find the date of the most recent backup of
		     the same graph that was done at a lower level.  If no
		     such entry is found, the beginning of time is assumed.
		     All files in the graph that have been modified since
		     this date are backed up.

    Access Control Lists (ACLs)
      If a file has optional ACL entries, the -A option is required to
      enable its recovery on a system where the ACL capability is not
      present.

 EXTERNAL INFLUENCES
    Environment Variables
      LC_COLLATE determines the order in which files are stored on the
      backup device and the order of output by the -I option.

      LC_TIME determines the format and contents of date and time strings.

      LC_MESSAGES determines the language in which messages are displayed.

      If LC_COLLATE, LC_TIME, and LC_MESSAGES are not all specified in the
      environment, or if either is 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"



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      (see lang(5)) is used instead of LANG.  If any internationalization
      variable contains an invalid setting, fbackup 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.

 RETURN VALUE
      fbackup returns one of the following values:

      0	 upon normal completion.

      1	 if it is interrupted but allowed to save its state for possible
	 restart.

      2	 if any error conditions prevent the session from completing.

      4	 if any warning conditions are encountered.

      If warnings occur, the operator should check the fbackup logs to
      verify the sanity of the backup.

 EXAMPLES
      In the following two examples, assume the graph of interest specifies
      all of /usr except /usr/lib (as described for the -g option above).

      The first example is a simple case where a full backup is done but the
      database file is not updated.  This can be invoked as follows:

	   /usr/sbin/fbackup -0i /usr -e /usr/lib -f /dev/rmt/c0t0d0BEST

      The second example is more complicated, and assumes the user wants to
      maintain a database of past fbackup sessions so that incremental
      backups are possible.

      If sufficient on-line storage is available, it may be desirable to
      keep several of the most recent index files on disk.  This eliminates
      the need to recover the index from the backup media to determine if
      the files to be recovered are on that set.  One method of maintaining
      on-line index files is outlined below.  The system administrator must
      do the following once before fbackup is run for the first time
      (creating intermediate level directories where necessary):

	   +  Create a suitable configuration file called config in the
	      directory /var/adm/fbackupfiles.

	   +  Create a graph file called usr-usrlib in the directory
	      /var/adm/fbackupfiles/graphs.

	   +  Create a directory called usr-usrlib in the directory
	      /var/adm/fbackupfiles/indices.



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 fbackup(1M)							 fbackup(1M)




      A shell script that performs the following tasks could be run for each
      fbackup session:

	   +  Build an index file path name based on both the graph file
	      used (passed as a parameter to the script) and the start time
	      of the session (obtained from the system).  For example:

		   /var/adm/fbackupfiles/indices/usr-usrlib/871128.15:17
		   (for Nov 28, 1987 at 3:17 PM)

	   +  Invoke fbackup with this path name as its index file name.
	      For example:

		   cd /var/adm/fbackupfiles
		   /usr/sbin/fbackup -0uc config -g graphs/usr-usrlib\
		      -I indices/usr-usrlib/871128.15:17\
			 -f /dev/rmt/c0t0d0BEST

      When the session completes successfully, the index is automatically
      placed in the proper location.

 WARNINGS
      fbackup consists of multiple executable objects, all of which are
      expected to reside in directory /usr/sbin.

      fbackup does not require special privileges.  However, if the user
      does not have access to a given file, the file is not backed up.

      For security reasons, configuration files and the chgvol and error
      executable files should only be writable by their owners.

      With release 10.20, HP-UX supports large files (greater than 2GB) and
      increased UID/GIDs (greater than 60,000).	 Archives containing files
      with these attributes would cause severe problems on systems that do
      not support the increased sizes.	For this reason, fbackup creates
      tapes with a new magic number ("FBACKUP_LABEL").	This prevents
      fbackup tape archives from being restored on pre-10.20 HP-UX systems.
      frecover still reads both tape formats so that fbackup tape archives
      created on pre-10.20 HP-UX systems can be restored.

      EOF marks are used for checkpointing on all magnetic tape devices.  On
      DLT tape devices, these EOF marks are also used for fast searching on
      a selective recovery; "fast searching" in this case means spacing to
      the nearest checkpoint before the desired file, and then reading until
      the file is found.  With this dual purpose for checkpoints, caution
      should be used when changing the checkpoint frequency parameter.

      Starting with HP-UX Release 8.0, fbackup does not back up network
      special files because RFA networking is obsolete.	 A warning message
      is issued if a network special file is encountered in the backup graph
      and the file is skipped.



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 fbackup(1M)							 fbackup(1M)




      The use of fbackup for backing up NFS mounted file systems is not
      guaranteed to work as expected if the backup is done as a privileged
      user.  This is due to the manner in which NFS handles privileged-user
      access by mapping user root and uid 0 to user nobody, usually uid -2,
      thus disallowing root privileges on the remote system to a root user
      on the local system.

      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.

      Due to present file-system limitations, files whose inode data, but
      not their contents, are modified while a backup is in progress might
      be omitted from the next incremental backup of the same graph.  Also,
      fbackup does not reset the inode change times of files to their
      original values.

      fbackup should not be used with no-rewind devices, for example,
      /dev/rmt/0mn.

      fbackup allocates resources that are not returned to the system if it
      is killed in an ungraceful manner.  If it is necessary to kill
      fbackup, send it a SIGTERM, not a SIGKILL.

      If sparse files are backed up without using data compression, a very
      large amount of media can be consumed.

      fbackup creates volumes with a format that makes duplication of
      volumes by dd impossible (see dd(1)).  Copying an fbackup volume
      created on one media type to another media type does not produce a
      valid fbackup volume on the new media because the formats of volumes
      on raw magnetic tape, on a regular file, and on rewritable optical
      disks are not identical.

      When configuring the parameter blocksperrecord (see -c option), the
      record size is limited by the maximum allowed for the tape drive.
      Common record sizes include 128 blocks for DLT and DDS tape drives,
      and 60 blocks for the HP7980.  Note also that the blocksize used in
      earlier releases (7.0 and before) was 512 bytes, whereas it is now
      1024 bytes.  This means that the same value specified in
      blocksperrecord in an earlier release creates blocks twice their
      earlier size in the current release; for example, a blocksperrecord
      parameter of 32 would create 16-Kbyte blocks at Release 7.0, but now



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 fbackup(1M)							 fbackup(1M)




      creates 32-Kbyte blocks.	If blocksperrecord exceeds the byte count
      allowed by the tape drive, the tape drive rejects the write, causing
      an error to be communicated to fbackup which fbackup interprets as a
      bad tape.	 The resulting write error message resembles the following:

	   fbackup (3013): Write error while writing backup at tape block 0.
	   Diagnostic error from tape 11...... SW_PROBLEM  (printed by driver on console)
	   fbackup (3102): Attempting to make this volume salvageable.
	   etc.

 DEPENDENCIES
    NFS
      Access control lists of networked files are summarized (as returned in
      st_mode by stat()), but not copied to the new file (see stat(2)).

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

	   mt lu X: Write must be a multiple of 512 bytes in QIC 120 or QIC
	   150

 AUTHOR
      fbackup was developed by HP.

 FILES
      /var/adm/fbackupfiles/dates		   database of past backups

 SEE ALSO
      cpio(1), ftio(1), dump(1M), frecover(1M), restore(1M), rmt(1M),
      stat(2), acl(5), mt(7).























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