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VCHANGER(8)			vchanger Manual			   VCHANGER(8)

       vchanger	- Virtual disk-based autochanger for Bacula network backup

       vchanger	[Options] config command [slot]	[device] [drive]

       vchanger	[Options] config CREATEVOLS mag_ndx count [start]

       vchanger	[Options] config LISTMAGS

       vchanger	[Options] config REFRESH

       The vchanger(8) utility is used to emulate and control a	virtual
       autochanger within the Bacula network backup system environment.	Backup
       volumes stored on multiple disk filesystems are mapped to a single set
       of virtual slots. This allows an	unlimited number of virtual drives and
       an unlimited number of virtual slots spread across an unlimited number
       of physical disk	drives to be assigned to a single autochanger. This
       allows unlimited	scaling	of the cirtual autochanger simply by adding
       additional disk drives.

       Vchanger	is primarily deigned for use with removable disk drives. Its
       ability to interact with	Bacula and determine removable drive mount
       points through udev allow for plug-n-play operation when	attaching and
       detaching removable disk	drives.

       The first argument, config, is required amd specifies the path to the
       vchanger.conf(5)	configuration file of the autochanger to be commanded.

       The second argument, command, is	the Bacula Autochanger Interface
       command to perform.

       The third argument, slot, is required for the LOAD, LOADED, and UNLOAD
       commands	and gives the slot number of the volume	to act upon.

       The fourth argument, device, is required	for the	LOAD, LOADED, and
       UNLOAD commands.	It normally specifies the device node of a tape	drive
       for tape	autochangers. For vcahnger, it is only required	as a place
       holder, and its value is	ignored.

       The fifth argument, drive, is required for the LOAD, LOADED, and	UNLOAD
       commands	and gives the zero-based drive number to act upon.

       Vchanger	implements the commands	defined	by the Bacula Autochanger
       Interface specification.	The following commands are supported.

	   List	slots, one line	each, in the format slot:label.

       LOAD slot device	drive
	   Load	the volume in slot slot	into drive drive.

       LOADED slot device drive
	   Print the slot number currently loaded into drive drive, or print 0
	   if the drive	is unloaded.

	   Print the number of slots.

       UNLOAD slot device drive
	   Unload the volume currently loaded in drive drive.

       Vchanger	also implements	the following undocumented comands

	   List	drive status followed by slot status, one line for each	drive
	   or slot, in the format type:number:status:label, where type is D
	   for a drive or S for	a slot,	number is the drive or slot number,
	   status is E for empty or F for full,	and label is the volume	label

       Additionally, the following extended commands are supported.

       CREATEVOLS mag_ndx count	[start]
	   Create count	volume files on	the magazine indexed by	mag_ndx.
	   Magazines are directories and/or filesystems	that have been defined
	   in the vchanger(5) configuration file given by config. The magazine
	   index is based on the order in which	the Magazine directives	appear
	   in the configuration	file, where index zero is the first
	   occurrence. Optionally, start specifies the minimum integer
	   uniqueness number to	append to a prefix string when generating
	   filenames for the created volume files. The default is to use a
	   uniqueness number greater than highest number currently used	for
	   any volume file on the selected magazine.

	   List	the status of all assigned magazines (directories and
	   filesystems), one per line, in the format mag:count:start:mnt,
	   where mag is	zero-based index of the	magazines specified in
	   configuration file config, count is the number of volume files on
	   that	magazine, start	is the virtual slot number of the beginning of
	   the range of	slots mapped to	the magazine's volume files, and mnt
	   is the magazine's directory/mountpoint if mounted, or blank if not
	   currently mounted.

	   Refresh state information for the autochanger defined by the
	   configuration file config, issuing an update	slots command to
	   Bacula if required.

       Bacula Interaction

       By default, vcahgner will invoke	bconsole and issue commands to Bacula
       when certain operator actions are needed. When anything happens that
       changes the current set of volume files being used, (the	virtual	slot
       to volume file mapping),	vchanger will invoke bconsole and issue	an
       update slots command. For example, when the operator attaches a
       removable drive defined as one of the changer's magazines, the volume
       files on	the removable drive must be mapped to virtual slots. Since the
       slot-to-volume mapping will have	changed, Bacula	will need to be
       informed	of the change via the update slots command. The	REFRESH
       command can be invoked to force vchanger	to update state	info and
       trigger update slots if needed.

       Additionally, when new volumes are created with the CREATEVOLS command,
       vchanger	will invoke bconsole and issue a label barcodes	command	to
       allow Bacula to write volume labels on the newly	created	volume files.

       -u, --user=uid
	   Override the	default	user to	run as when invoked by root. The
	   default is normally specified in the	configuration file given by

       -g, --group=gid
	   Override the	default	group to run as	when invoked by	root. The
	   default is normally specified in the	configuration file given by

	   Overrides the name of the pool into which volumes created by	the
	   CREATEVOLS command will be placed when vchanger is configured to
	   label new volumes by	sending	Bacula a label barcodes	command. The
	   default is given by the Default Pool	setting	in the configuration

       -l, --label=prefix
	   Overrides the default volume	label prefix when generating names for
	   new volume files created by the CREATEVOLS command. The default is
	   name_ndx, where name	is the autochanger name	and ndx	is the
	   magazine index.

	   Displays command help for the vchanger command.

	   Displays vchanger version information.

       See the vchangerHowto.html file included	in the doc directory of	the
       source distribution for more detailed documentation.


       Copyright 2006-2020 Josh	Fisher

       This is free software; See the source for copying conditions. There is
       NO warranty; not	even for MERCHANTABILITY or FITNESS FOR	A PARTICULAR

       Josh Fisher <>

vchanger 1.0.3			  05/11/2020			   VCHANGER(8)


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