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BACKUP(8)		     AFS Command Reference		     BACKUP(8)

       backup -	Introduction to	the backup command suite

       The commands in the backup command suite	are the	administrative
       interface to the	AFS Backup System. There are several categories	of
       commands	in the suite:

       o   Commands to copy data from AFS volumes to tape or a backup data
	   file, and to	restore	it to the file system: backup diskrestore,
	   backup dump,	backup volrestore, and backup volsetrestore.

       o   Commands to administer the records in the Backup Database: backup
	   adddump, backup addhost, backup addvolentry,	backup addvolset,
	   backup deldump, backup deletedump, backup delhost, backup
	   delvolentry,	backup delvolset, backup dumpinfo, backup listdumps,
	   backup listhosts, backup listvolsets, backup	scantape, backup
	   setexp, and backup volinfo.

       o   Commands to write and read tape labels: backup labeltape and	backup

       o   Commands to list and	change the status of backup operations and the
	   machines performing them: backup jobs, backup kill, and backup

       o   Commands to enter and leave interactive mode: backup	interactive
	   and backup quit.

       o   Commands to check for and repair corruption in the Backup Database:
	   backup dbverify, backup restoredb, and backup savedb.

       o   Commands to obtain help: backup apropos and backup help.

       o   A command to	display	the OpenAFS command suite version: backup

       The backup command interpreter interacts	with two other processes:

       o   The Backup Server (buserver)	process. It maintains the Backup
	   Database, which stores most of the administrative information used
	   by the Backup System. In the	standard configuration,	the Backup
	   Server runs on each database	server machine in the cell, and	uses
	   AFS's distributed database technology, Ubik,	to synchronize its
	   copy	of the database	with the copies	on the other database server

       o   The Backup Tape Coordinator (butc) process. A separate instance of
	   the process controls	each tape device or backup data	file used to
	   dump	or restore data. The Tape Coordinator runs on a	Tape
	   Coordinator machine,	which is an AFS	server or client machine that
	   has one or more tape	devices	attached, or has sufficient disk space
	   to accommodate one or more backup data files	on its local disk.

	   Each	Tape Coordinator must be registered in the Backup Database and
	   in the /var/openafs/backup/tapeconfig configuration file on the
	   Tape	Coordinator machine's local disk, and information in the two
	   places must be consistent for proper	Backup System performance. The
	   optional /var/openafs/backup/CFG_device_name	for each Tape
	   Coordinator records information used	to automate its	operation.

       In addition to the standard command line	interface, the backup command
       suite provides an interactive interface,	which has several useful
       features	described in backup_interactive(8).  Three of the commands in
       the suite are available only in interactive mode: backup	jobs, backup
       kill, and backup	quit

       The following options are available on many commands in the backup
       suite. The reference page for each command also lists them, but they
       are described here in greater detail.

       -cell <cell name>
	   Names the cell in which to run the command. It is acceptable	to
	   abbreviate the cell name to the shortest form that distinguishes it
	   from	the other entries in the /usr/local/etc/openafs/CellServDB
	   file	on the local machine. If the -cell argument is omitted,	the
	   command interpreter determines the name of the local	cell by
	   reading the following in order:

	   o   The value of the	AFSCELL	environment variable.

	   o   The local /usr/local/etc/openafs/ThisCell file.

	   Do not combine the -cell and	-localauth options. A command on which
	   the -localauth flag is included always runs in the local cell (as
	   defined in the server machine's local
	   /usr/local/etc/openafs/server/ThisCell file), whereas a command on
	   which the -cell argument is included	runs in	the specified foreign

	   The -cell argument is not available on commands issued in
	   interactive mode. The cell defined when the backup command
	   interpreter enters interactive mode applies to all commands issued
	   during the interactive session.

	   Prints a command's online help message on the standard output
	   stream. Do not combine this flag with any of	the command's other
	   options; when it is provided, the command interpreter ignores all
	   other options, and only prints the help message.

	   Constructs a	server ticket using the	server encryption key with the
	   highest key version number in the local
	   /usr/local/etc/openafs/server/KeyFile file. The backup command
	   interpreter presents	the ticket, which never	expires, to the	Backup
	   Server, Volume Server and Volume Location (VL) Server during	mutual

	   Use this flag only when issuing a command on	a server machine;
	   client machines do not usually have a
	   /usr/local/etc/openafs/server/KeyFile file.	The issuer of a
	   command that	includes this flag must	be logged on to	the server
	   machine as the local	superuser "root". The flag is useful for
	   commands invoked by an unattended application program, such as a
	   process controlled by the UNIX cron utility or by a cron entry in
	   the machine's /usr/local/etc/openafs/BosConfig file.	It is also
	   useful if an	administrator is unable	to authenticate	to AFS but is
	   logged in as	the local superuser "root".

	   Do not combine the -cell and	-localauth options. A command on which
	   the -localauth flag is included always runs in the local cell (as
	   defined in the server machine's local
	   /usr/local/etc/openafs/server/ThisCell file), whereas a command on
	   which the -cell argument is included	runs in	the specified foreign

	   The -localauth argument is not available on commands	issued in
	   interactive mode. The local identity	and AFS	tokens with which the
	   backup command interpreter enters interactive mode apply to all
	   commands issued during the interactive session.

       -portoffset <TC port offset>
	   Specifies the port offset number of the Tape	Coordinator that is to
	   execute the backup command. The port	offset number uniquely
	   identifies a	pairing	of a Tape Coordinator (butc) process and tape
	   device or backup data file.

	   The backup command interpreter and Tape Coordinator process
	   communicate via a UDP socket, or port. Before issuing a backup
	   command that	involves reading or writing a tape, the	backup
	   operator must start a butc process that controls the	appropriate
	   tape	device and listens for requests	sent to	its port number. If a
	   Backup System machine has multiple tape devices attached, they can
	   perform backup operations simultaneously because each device	has
	   its own associated butc process and port offset number.

	   The Backup System associates	a tape capacity	and file mark size
	   with	each port offset (as defined in	the tapeconfig file). For a
	   compressing tape device, the	capacity and file mark values differ
	   for compression and non-compression modes, so the two modes have
	   distinct port offset	numbers.

	   The Backup Database can store up to 58,511 port offsets, so the
	   legal values	for this argument are the integers 0 through 58510. If
	   the issuer omits the	argument, it defaults to 0. (The limit of
	   58,511 port offsets results from the	fact that UDP socket numbers
	   are identified by a 16-bit integer, and the lowest socket number
	   used	by the Backup System is	7025. The largest number that a	16-bit
	   integer can represent is 65,535. Subtracting	7,025 yields 58,510.
	   The addition	of port	offset 0 (zero)	increases the maximum to

	   Although it is possible to define up	to 58,511 port offset numbers
	   for a cell, it is not possible to run 58,511	tape devices
	   simultaneously, due to the following	limits:

	   o   The maximum number of dump or restore operations	that can run
	       simultaneously is 64.

	   o   The maximum number of tape devices that can work	together on a
	       restore operation is 128	(that is the maximum number of values
	       that can	be provided for	the -portoffset	argument to the	backup
	       diskrestore, backup volrestore, or backup volsetrestore

	   The Backup System does not reserve UDP sockets. If another
	   application is already using	the Tape Coordinator's socket when it
	   tries to start, the butc process fails and the following error
	   message appears at the shell	prompt:

	      bind: Address already in use
	      rxi_GetUDPSocket:	bind failed

       To issue	any backup command that	accesses the Backup Database only, the
       issuer must be listed in	the /usr/local/etc/openafs/server/UserList
       file on every machine where the Backup Server is	running. To issue any
       backup command that accesses volume data, the issuer must appear	in the
       UserList	file on	every Backup Server machine, every Volume Location
       (VL) Server machine, and	every file server machine that houses affected
       volumes.	By convention, a common	UserList file is distributed to	all
       database	server and file	server machines	in the cell. See the chapter
       on privileged users in the OpenAFS Administration Guide for more
       information on this type	of privilege.

       If the -localauth flag is included, the user must instead be logged on
       as the local superuser "root" on	the server machine where the backup
       command is issued.

       BosConfig(5), CellServDB(5), KeyFile(5),	ThisCell(5), UserList(5),
       butc(5),	tapeconfig(5), backup_adddump(8), backup_addhost(8),
       backup_addvolentry(8), backup_addvolset(8), backup_apropos(8),
       backup_dbverify(8), backup_deldump(8), backup_deletedump(8),
       backup_delhost(8), backup_delvolentry(8), backup_delvolset(8),
       backup_diskrestore(8), backup_dump(8), backup_dumpinfo(8),
       backup_help(8), backup_interactive(8), backup_jobs(8), backup_kill(8),
       backup_labeltape(8), backup_listdumps(8), backup_listhosts(8),
       backup_listvolsets(8), backup_quit(8), backup_readlabel(8),
       backup_restoredb(8), backup_savedb(8), backup_scantape(8),
       backup_setexp(8), backup_status(8), backup_volinfo(8),
       backup_volrestore(8), backup_volsetrestore(8), buserver(8), butc(8)

       IBM Corporation 2000. <> All Rights Reserved.

       This documentation is covered by	the IBM	Public License Version 1.0.
       It was converted	from HTML to POD by software written by	Chas Williams
       and Russ	Allbery, based on work by Alf Wachsmann	and Elizabeth Cassell.

OpenAFS				  2016-12-14			     BACKUP(8)


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