5 \label{NewFeaturesChapter}
6 \index[general]{New Features}
8 This chapter presents the new features added to the development 2.5.x
9 versions to be released as Bacula version 3.0.0 near the end of 2008.
12 \index[general]{Accurate Backup}
14 As with most other backup programs, Bacula decides what files to backup for
15 Incremental and Differental backup by comparing the change (st\_ctime) and
16 modification (st\_mtime) times of the file to the time the last backup
17 completed. If one of those two times is different than from last backup time,
18 then the file will be backed up. This does not, however, permit tracking what
19 files have been deleted and will miss any file with an old time that may have
20 been restored or moved on the client filesystem.
22 \subsection{Accurate = \lt{}yes|no\gt{}}
23 If the {\bf Accurate = \lt{}yes|no\gt{}} directive is enabled (default no) in
24 the Job resource, the job will be run as an Accurate Job. For a {\bf Full}
25 backup, there is no difference, but for {\bf Differential} and {\bf
26 Incremental} backups, the Director will send a list of all previous files
27 backed up, and the File daemon will use that list to determine if any new files
28 have been added or or moved and if any files have been deleted. This allows
29 Bacula to make an accurate backup of your system to that point in time so that
30 if you do a restore, it will restore your system exactly. One note of caution
31 about using Accurate backup is that it requires more resources (CPU and memory)
32 on both the Director and the Client machines to create the list of previous
33 files backed up, to send that list to the File daemon, for the File daemon to
34 keep the list (possibly very big) in memory, and for the File daemon to do
35 comparisons between every file in the FileSet and the list.
39 \index[general]{Copy Jobs}
40 A new {\bf Copy} job type has been implemented. It is essentially
41 identical to the existing Migration feature with the exception that
42 the Job that is copied is left unchanged. This essentially creates
43 two identical copies of the same backup. The Copy Job runs without
44 using the File daemon by copying the data from the old backup Volume to
45 a different Volume in a different Pool. See the Migration documentation
46 for additional details.
48 \section{Virtual Backup (Vbackup)}
49 \index[general]{Virtual Backup}
50 \index[general]{Vbackup}
52 Bacula's virtual backup feature is often called Synthetic Backup or
53 Consolidation in other backup products. It permits you to consolidate
54 the previous Full backup plus the most recent Differential backup and any
55 subsequent Incremental backups into a new Full backup. This is accomplished
56 without contacting the client by reading the previous backup data and
57 writing it to a volume in a different pool.
59 In some respects the Vbackup feature works similar to a Migration job, in
60 that Bacula normally reads the data from the pool specified in the
61 Job resource, and writes it to the {\bf Next Pool} specified in the
62 Job resource. The input Storage resource and the Output Storage resource
65 The Vbackup is enabled on a Job by Job in the Job resource by specifying
66 a level of {\bf VirtualFull}.
68 A typical Job resource definition might look like the following:
82 # Default pool definition
86 Recycle = yes # Automatically recycle Volumes
87 AutoPrune = yes # Prune expired volumes
88 Volume Retention = 365d # one year
96 Recycle = yes # Automatically recycle Volumes
97 AutoPrune = yes # Prune expired volumes
98 Volume Retention = 365d # one year
102 # Definition of file storage device
109 Maximum Concurrent Jobs = 5
112 # Definition of DDS Virtual tape disk storage device
115 Address = localhost # N.B. Use a fully qualified name here
118 Media Type = DiskChangerMedia
119 Maximum Concurrent Jobs = 4
124 Then in bconsole or via a Run schedule, you would run the job as:
127 run job=MyBackup level=Full
128 run job=MyBackup level=Incremental
129 run job=MyBackup level=Differential
130 run job=MyBackup level=Incremental
131 run job=MyBackup level=Incremental
134 So providing there were changes between each of those jobs, you would end up
135 with a Full backup, a Differential, which includes the first Incremental
136 backup, then two Incremental backups. All the above jobs would be written to
137 the {\bf Default} pool.
139 To consolidate those backups into a new Full backup, you would run the
143 run job=MyBackup level=VirtualFull
146 And it would produce a new Full backup without using the client, and the output
147 would be written to the {\bf Full} Pool which uses the Diskchanger Storage.
149 \section{Duplicate Job Control}
150 \index[general]{Duplicate Jobs}
151 The new version of Bacula provides four new directives that
152 give additional control over what Bacula does if duplicate jobs
153 are started. A duplicate job in the sense we use it here means
154 a second or subsequent job with the same name starts. This
155 happens most frequently when the first job runs longer than expected because no
158 The four directives each take as an argument a {\bf yes} or {\bf no} value and
159 are specified in the Job resource.
163 \subsection{Allow Duplicate Jobs = \lt{}yes|no\gt{}}
164 If this directive is enabled duplicate jobs will be run. If
165 the directive is set to {\bf no} (default) then only one job of a given name
166 may run at one time, and the action that Bacula takes to ensure only
167 one job runs is determined by the other directives (see below).
169 \subsection{Allow Higher Duplicates = \lt{}yes|no\gt{}}
170 If this directive is set to {\bf yes} (default) the job with a higher
171 priority (lower priority number) will be permitted to run. If the
172 priorities of the two jobs are the same, the outcome is determined by
173 other directives (see below).
175 \subsection{Cancel Queued Duplicates = \lt{}yes|no\gt{}}
176 If this directive is set to {\bf yes} (default) any job that is
177 already queued to run but not yet running will be canceled.
179 \subsection{Cancel Running Duplicates = \lt{}yes|no\gt{}}
180 If this directive is set to {\bf yes} any job that is already running
181 will be canceled. The default is {\bf no}.
184 \section{TLS Authentication}
185 \index[general]{TLS Authentication}
186 In Bacula version 2.5.x and later, in addition to the normal Bacula
187 CRAM-MD5 authentication that is used to authenticate each Bacula
188 connection, you can specify that you want TLS Authentication as well,
189 which will provide more secure authentication.
191 This new feature uses Bacula's existing TLS code (normally used for
192 communications encryption) to do authentication. To use it, you must
193 specify all the TLS directives normally used to enable communications
194 encryption (TLS Enable, TLS Verify Peer, TLS Certificate, ...) and
197 \subsection{TLS Authenticate = yes}
199 TLS Authenticate = yes
202 in the main daemon configuration resource (Director for the Director,
203 Client for the File daemon, and Storage for the Storage daemon).
205 When {\bf TLS Authenticate} is enabled, after doing the CRAM-MD5
206 authentication, Bacula will do the normal TLS authentication, then TLS
207 encryption will be turned off.
209 If you want to encrypt communications data, do not turn on {\bf TLS
212 \section{bextract non-portable Win32 data}
213 \index[general]{bextract handles Win32 non-portable data}
214 {\bf bextract} has been enhanced to be able to restore
215 non-portable Win32 data to any OS. Previous versions were
216 unable to restore non-portable Win32 data to machines that
217 did not have the Win32 BackupRead and BackupWrite API calls.
219 \section{State File updated at Job Termination}
220 \index[general]{State File}
221 In previous versions of Bacula, the state file, which provides a
222 summary of previous jobs run in the {\bf status} command output was
223 updated only when Bacula terminated, thus if the daemon crashed, the
224 state file might not contain all the run data. This version of
225 the Bacula daemons updates the state file on each job termination.
227 \section{MaxFullInterval = \lt{}time-interval\gt{}}
228 \index[general]{MaxFullInterval}
229 The new Job resource directive {\bf Max Full Interval = \lt{}time-interval\gt{}}
230 can be used to specify the maximum time interval between {\bf Full} backup
231 jobs. When a job starts, if the time since the last Full backup is
232 greater than the specified interval, and the job would normally be an
233 {\bf Incremental} or {\bf Differential}, it will be automatically
234 upgraded to a {\bf Full} backup.
236 \section{MaxDiffInterval = \lt{}time-interval\gt{}}
237 \index[general]{MaxDiffInterval}
238 The new Job resource directive {\bf Max Diff Interval = \lt{}time-interval\gt{}}
239 can be used to specify the maximum time interval between {\bf Differential} backup
240 jobs. When a job starts, if the time since the last Differential backup is
241 greater than the specified interval, and the job would normally be an
242 {\bf Incremental}, it will be automatically
243 upgraded to a {\bf Differential} backup.
245 \section{Honor No Dump Flag = \lt{}yes|no\gt{}}
246 \index[general]{MaxDiffInterval}
247 On FreeBSD systems, each file has a {\bf no dump flag} that can be set
248 by the user, and when it is set it is an indication to backup programs
249 to not backup that particular file. This version of Bacula contains a
250 new Options directive within a FileSet resource, which instructs Bacula to
251 obey this flag. The new directive is:
254 Honor No Dump Flag = yes|no
257 The default value is {\bf no}.
260 \section{Ignore Dir = \lt{}filename-string\gt{}}
261 \index[general]{IgnoreDir}
262 The {\bf Ignore Dir = \lt{}filename\gt{}} is a new directive that can be added to the Include
263 section of the FileSet resource. If the specified
264 filename is found on the Client in any directory to be backed up,
265 the whole directory will be ignored (not backed up).
269 # List of files to be backed up
277 IgnoreDir = .excludeme
282 But in /home, there may be hundreds of directories of users and some
283 people want to indicate that they don't want to have certain
284 directories backed up. For example, with the above FileSet, if
285 the user or sysadmin creates a file named {\bf .excludeme} in
286 specific directories, such as
289 /home/user/www/cache/.excludeme
290 /home/user/temp/.excludeme
293 then Bacula will not backup the two directories named:
300 NOTE: subdirectories will not be backed up. That is, the directive
301 applies to the two directories in question and any children (be they
302 files, directories, etc).
306 \section{Bacula Plugins}
307 \index[general]{Plugin}
308 Support for shared object plugins has been implemented in the Linux
309 (and Unix) File daemon. The API will be documented separately in
310 the Developer's Guide or in a new document. For the moment, there is
311 a single plugin named {\bf bpipe} that allows an external program to
312 get control to backup and restore a file.
314 Plugins are also planned (partially implemented) in the Director and the
315 Storage daemon. The code is also implemented to work on Win32 machines,
316 but it has not yet been tested.
318 \subsection{Plugin Directory}
319 Each daemon (DIR, FD, SD) has a new {\bf Plugin Directory} directive that may
320 be added to the daemon definition resource. The directory takes a quoted
321 string argument, which is the name of the directory in which the daemon can
322 find the Bacula plugins. If this directive is not specified, Bacula will not
323 load any plugins. Since each plugin has a distinctive name, all the daemons
324 can share the same plugin directory.
328 \subsection{Plugin Options}
329 The {\bf Plugin Options} directive takes a quoted string
330 arguement (after the equal sign) and may be specified in the
331 Job resource. The options specified will be passed to the plugin
332 when it is run. The value defined in the Job resource can be modified
333 by the user when he runs a Job via the {\bf bconsole} command line
336 Note: this directive may be specified, but it is not yet passed to
337 the plugin (i.e. not fully implemented).
339 \subsection{Plugin Options ACL}
340 The {\bf Plugin Options ACL} directive may be specified in the
341 Director's Console resource. It functions as all the other ACL commands
342 do by permitting users running restricted consoles to specify a
343 {\bf Plugin Options} that overrides the one specified in the Job
344 definition. Without this directive restricted consoles may not modify
347 \subsection{Plugin = \lt{}plugin-command-string\gt{}}
348 The {\bf Plugin} directive is specified in the Include section of
349 a FileSet resource where you put your {\bf File = xxx} directives.
365 In the above example, when the File daemon is processing the directives
366 in the Include section, it will first backup all the files in {\bf /home}
367 then it will load the plugin named {\bf bpipe} (actually bpipe-dir.so) from
368 the Plugin Directory. The syntax and semantics of the Plugin directive
369 require the first part of the string up to the colon (:) to be the name
370 of the plugin. Everything after the first colon is ignored by the File daemon but
371 is passed to the plugin. Thus the plugin writer may define the meaning of the
372 rest of the string as he wishes.
374 Please see the next section for information about the {\bf bpipe} Bacula
377 \section{The bpipe Plugin}
378 The {\bf bpipe} plugin is provided in the directory src/plugins/fd/bpipe-fd.c of
379 the Bacula source distribution. When the plugin is compiled and linking into
380 the resulting dynamic shared object (DSO), it will have the name {\bf bpipe-fd.so}.
382 The purpose of the plugin is to provide an interface to any system program for
383 backup and restore. As specified above the {\bf bpipe} plugin is specified in
384 the Include section of your Job's FileSet resource. The full syntax of the
385 plugin directive as interpreted by the {\bf bpipe} plugin (each plugin is free
386 to specify the sytax as it wishes) is:
389 Plugin = "<field1>:<field2>:<field3>:<field4>"
394 \item {\bf field1} is the name of the plugin with the trailing {\bf -fd.so}
395 stripped off, so in this case, we would put {\bf bpipe} in this field.
397 \item {\bf field2} specifies the namespace, which for {\bf bpipe} is the
398 pseudo path and filename under which the backup will be saved. This pseudo
399 path and filename will be seen by the user in the restore file tree.
400 For example, if the value is {\bf /MYSQL/regress.sql}, the data
401 backed up by the plugin will be put under that "pseudo" path and filename.
402 You must be careful to choose a naming convention that is unique to avoid
403 a conflict with a path and filename that actually exists on your system.
405 \item {\bf field3} for the {\bf bpipe} plugin
406 specifies the "reader" program that is called by the plugin during
407 backup to read the data. {\bf bpipe} will call this program by doing a
410 \item {\bf field4} for the {\bf bpipe} plugin
411 specifies the "writer" program that is called by the plugin during
412 restore to write the data back to the filesystem.
415 Putting it all together, the full plugin directive line might look
419 Plugin = "bpipe:/MYSQL/regress.sql:mysqldump -f
420 --opt --databases bacula:mysql"
423 The directive has been split into two lines, but within the {\bf bacula-dir.conf} file
424 would be written on a single line.
426 This causes the File daemon to call the {\bf bpipe} plugin, which will write
427 its data into the "pseudo" file {\bf /MYSQL/regress.sql} by calling the
428 program {\bf mysqldump -f --opt --database bacula} to read the data during
429 backup. The mysqldump command outputs all the data for the database named
430 {\bf bacula}, which will be read by the plugin and stored in the backup.
431 During restore, the data that was backed up will be sent to the program
432 specified in the last field, which in this case is {\bf mysql}. When
433 {\bf mysql} is called, it will read the data sent to it by the plugn
434 then write it back to the same database from which it came ({\bf bacula}
437 The {\bf bpipe} plugin is a generic pipe program, that simply transmits
438 the data from a specified program to Bacula for backup, and then from Bacula to
439 a specified program for restore.
441 By using different command lines to {\bf bpipe},
442 you can backup any kind of data (ASCII or binary) depending
443 on the program called.
445 \section{Microsoft Exchange Server 2003/2007 Plugin}
447 \subsection{Concepts}
449 Microsoft Exchange organises its storage into Storage Groups with
450 Databases inside them. A default installation of Exchange will have a
451 single Storage Group called 'First Storage Group', with two Databases
452 inside it, "Mailbox Store (SERVER NAME)" and
453 "Public Folder Store (SERVER NAME)",
454 which hold user email and public folders respectively.
456 In the default configuration, Exchange logs everything that happens to
457 log files, such that if you have a backup, and all the log files since,
458 you can restore to the present time. Each Storage Group has its own set
459 of log files and operates independently of any other Storage Groups. At
460 the Storage Group level, the logging can be turned off by enabling a
461 function called "Enable circular logging". At this time the Exchange
462 plugin will not function if this option is enabled.
464 The plugin allows backing up of entire storage groups, and the restoring
465 of entire storage groups or individual databases. Backing up and
466 restoring at the individual mailbox or email item is not supported but
467 can be simulated by use of the Recovery Storage Group (see below).
469 \subsection{Installing}
471 The Exchange plugin requires a DLL that is shipped with Microsoft
472 Exchanger Server called {\bf esebcli2.dll}. Assuming Exchange is installed
473 correctly the Exchange plugin should find this automatically and run
474 without any additional installation.
476 If the DLL can not be found automatically it will need to be copied into
477 the Bacula installation
478 directory (eg C:\verb+\+Program Files\verb+\+Bacula\verb+\+bin). The Exchange API DLL is
479 named esebcli2.dll and is found in C:\verb+\+Program Files\verb+\+Exchsrvr\verb+\+bin on a
480 default Exchange installation.
482 \subsection{Backup up}
484 To back up an Exchange server the Fileset definition must contain at
485 least 'Plugin = "exchange:/@EXCHANGE/Microsoft Information Store"' for
486 the backup to work correctly. The 'exchange:' bit tells Bacula to look
487 for the exchange plugin, the '@EXCHANGE' bit makes sure all the backed
488 up files are prefixed with something that isn't going to share a name
489 with something outside the plugin, and the 'Microsoft Information Store'
490 bit is required also. It is also possible to add the name of a storage
491 group to the 'Plugin =' line, eg 'Plugin =
492 "exchange:/@EXCHANGE/Microsoft Information Store/First Storage Group"'
493 if you want only a single storage group backed up.
495 Additionally, you can suffix the 'Plugin =' directive with
496 ':notrunconfull' which will tell the plugin not to truncate the Exchange
497 database at the end of a full backup.
499 An Incremental or Differential backup will backup only the database logs
500 for each Storage Group by inspecting the 'modified date' on each
501 physical log file. Because of the way the Exchange API works, the last
502 logfile backed up on each backup will always be backed up by the next
503 Incremental or Differential backup too. This adds 5MB to each
504 Incremental or Differential backup size but otherwise does not cause any
507 \subsection{Restoring}
509 The restore operation is much the same as a normal Bacula restore, with
510 the following provisos:
513 \item The 'Where' restore option must not be specified
514 \item Each Database directory must be marked as a whole. You cannot just
515 select (say) the .edb file and not the others.
516 \item If a Storage Group is restored, the directory of the Storage Group
518 \item It is possible to restore only a subset of the available log files,
519 but they {\bf must} be contiguous. Exchange will fail to restore correctly
520 if a log file is missing from the sequence of log files
521 \item Each database to be restored must be dismounted and marked as 'Can be
522 overwritten by restore'
523 \item If an entire Storage Group is to be restored (eg all databases and
524 logs in the Storage Group), then it is best to manually delete the
525 database files from the server (eg C:\verb+\+Program Files\verb+\+Exchsrvr\verb+\+mdbdata\verb+\+*)
526 as Exchange can get confused by stray log files lying around.
529 \subsection{Restoring to the Recovery Storage Group}
531 The concept of the Recovery Storage Group is well documented by
533 \elink{http://support.microsoft.com/kb/824126}{http://support.microsoft.com/kb/824126},
534 but to briefly summarise...
536 Microsoft Exchange allows the creation of an additional Storage Group
537 called the Recovery Storage Group, which is used to restore an older
538 copy of a database (eg before a mailbox was deleted) into without
539 messing with the current live data. This is required as the Standard and
540 Small Business Server versions of Exchange can not ordinarily have more
541 than one Storage Group.
543 To create the Recovery Storage Group, drill down to the Server in
544 Exchange System Manager, right click, and select
545 {\bf "New -> Recovery Storage Group..."}. Accept or change the file locations and click OK. On
546 the Recovery Storage Group, right click and select
547 {\bf "Add Database to Recover..."} and select the database you will be restoring.
549 In Bacula, select the Database and the log files, making sure to mark
550 the Storage Group directory itself too. Once you have selected the files
551 to back up, use the RegexWhere clause to remove the prefix of
552 "/@EXCHANGE/Microsoft Information Store/\lt{}storage group name\gt{}/" and
553 replace it with "/@EXCHANGE/Microsoft Information Store/Recovery Storage Group/".
554 Then run the restore.
558 This plugin is still being developed, so you should consider it
559 currently in BETA test, and thus use in a production environment
560 should be done only after very careful testing.
562 The "Enable Circular Logging" option cannot be enabled or the plugin
565 Exchange insists that a successful Full backup must have taken place if
566 an Incremental or Differential backup is desired, and the plugin will
567 fail if this is not the case. If a restore is done, Exchange will
568 require that a Full backup be done before an Incremental or Differential
571 The plugin will most likely not work well if another backup application
572 (eg NTBACKUP) is backing up the Exchange database, especially if the
573 other backup application is truncating the log files.
575 The Exchange plugin has not been tested with the {\bf Accurate} option, so
576 we recommend either carefully testing or that you avoid this option for
579 The Exchange plugin is not called during processing the bconsole {\bf estimate} command,
580 and so anything that would be backed up by the plugin will not be added
581 to the estimate total that is displayed.
584 \section{libdbi Framework}
585 As a general guideline, Bacula has support for a few catalog database drivers
586 (MySQL, PostgreSQL, SQLite)
587 coded natively by the Bacula team. With the libdbi implementation, which is a
588 Bacula driver that uses libdbi to access the catalog, we have an open field to
589 use many different kinds database engines following the needs of users.
591 The according to libdbi (http://libdbi.sourceforge.net/) project: libdbi
592 implements a database-independent abstraction layer in C, similar to the
593 DBI/DBD layer in Perl. Writing one generic set of code, programmers can
594 leverage the power of multiple databases and multiple simultaneous database
595 connections by using this framework.
597 Currently the libdbi driver in Bacula project only supports the same drivers
598 natively coded in Bacula. However the libdbi project has support for many
599 others database engines. You can view the list at
600 http://libdbi-drivers.sourceforge.net/. In the future all those drivers can be
601 supported by Bacula, however, they must be tested properly by the Bacula team.
603 Some of benefits of using libdbi are:
605 \item The possibility to use proprietary databases engines in which your
606 proprietary licenses prevent the Bacula team from developing the driver.
607 \item The possibility to use the drivers written for the libdbi project.
608 \item The possibility to use other database engines without recompiling Bacula
609 to use them. Just change one line in bacula-dir.conf
610 \item Abstract Database access, this is, unique point to code and profiling
611 catalog database access.
614 The following drivers have been tested:
616 \item PostgreSQL, with and without batch insert
617 \item Mysql, with and without batch insert
622 In the future, we will test and approve to use others databases engines
623 (proprietary or not) like DB2, Oracle, Microsoft SQL.
625 To compile Bacula to support libdbi we need to configure the code with the
626 --with-dbi and --with-dbi-driver=[database] ./configure options, where
627 [database] is the database engine to be used with Bacula (of course we can
628 change the driver in file bacula-dir.conf, see below). We must configure the
629 access port of the database engine with the option --with-db-port, because the
630 libdbi framework doesn't know the default access port of each database.
632 The next phase is checking (or configuring) the bacula-dir.conf, example:
636 dbdriver = dbi:mysql; dbaddress = 127.0.0.1; dbport = 3306
637 dbname = regress; user = regress; password = ""
641 The parameter {\bf dbdriver} indicates that we will use the driver dbi with a
642 mysql database. Currently the drivers supported by Bacula are: postgresql,
643 mysql, sqlite, sqlite3; these are the names that may be added to string "dbi:".
645 The following limitations apply when Bacula is set to use the libdbi framework:
646 - Not tested on the Win32 platform
647 - A little performance is lost if comparing with native database driver.
648 The reason is bound with the database driver provided by libdbi and the
649 simple fact that one more layer of code was added.
651 It is important to remember, when compiling Bacula with libdbi, the
652 following packages are needed:
654 \item libdbi version 1.0.0, http://libdbi.sourceforge.net/
655 \item libdbi-drivers 1.0.0, http://libdbi-drivers.sourceforge.net/
658 You can download them and compile them on your system or install the packages
659 from your OS distribution.
662 \section{Display Autochanger Content}
663 \index[general]{StatusSlots}
665 The {\bf status slots storage=\lt{}storage-name\gt{}} command displays autochanger content.
669 Slot | Volume Name | Status | Media Type | Pool |
670 ------+---------------+----------+-------------------+------------|
671 1 | 00001 | Append | DiskChangerMedia | Default |
672 2 | 00002 | Append | DiskChangerMedia | Default |
673 3*| 00003 | Append | DiskChangerMedia | Scratch |
678 If you an asterisk ({\bf *}) appears after the slot number, you must run an
679 {\bf update slots} command to synchronize autochanger content with your
682 \section{Miscellaneous}
683 \index[general]{Misc New Features}
685 \subsection{Allow Mixed Priority = \lt{}yes|no\gt{}}
686 This directive is only implemented in version 2.5 and later. When
687 set to {\bf yes} (default {\bf no}), this job may run even if lower
688 priority jobs are already running. This means a high priority job
689 will not have to wait for other jobs to finish before starting.
690 The scheduler will only mix priorities when all running jobs have
693 Note that only higher priority jobs will start early. Suppose the
694 director will allow two concurrent jobs, and that two jobs with
695 priority 10 are running, with two more in the queue. If a job with
696 priority 5 is added to the queue, it will be run as soon as one of
697 the running jobs finishes. However, new priority 10 jobs will not
698 be run until the priority 5 job has finished.
700 \subsection{Bootstrap File Directive -- FileRegex}
701 {\bf FileRegex} is a new command that can be added to the bootstrap
702 (.bsr) file. The value is a regular expression. When specified, only
703 matching filenames will be restored.
705 During a restore, if all File records are pruned from the catalog
706 for a Job, normally Bacula can restore only all files saved. That
707 is there is no way using the catalog to select individual files.
708 With this new command, Bacula will ask if you want to specify a Regex
709 expression for extracting only a part of the full backup.
712 \subsection{Virtual Tape Emulation}
713 We now have a Virtual Tape emulator that allows us to run though 99.9\% of
714 the tape code but actually reading and writing to a disk file. Used with the
715 \textbf{disk-changer} script, you can now emulate an autochanger with 10 drives
716 and 700 slots. This feature is most useful in testing. It is enabled
717 by using {\bf Device Type = vtape} in the Storage daemon's Device
718 directive. This feature is only implemented on Linux machines.
720 \subsection{Bat Enhancements}
721 Bat (the Bacula Administration Tool) GUI program has been significantly
722 enhanced and stabilized. In particular, there are new table based status
723 commands; it can now be easily localized using Qt4 Linguist.
725 The Bat communications protocol has been significantly enhanced to improve
728 \subsection{RunScript Enhancements}
729 The {\bf RunScript} resource has been enhanced to permit multiple
730 commands per RunScript. Simply specify multiple {\bf Command} directives
737 Command = "/bin/echo test"
738 Command = "/bin/echo an other test"
739 Command = "/bin/echo 3 commands in the same runscript"
746 A new Client RunScript {\bf RunsWhen} keyword of {\bf AfterVSS} has been implemented, which
747 runs the command after the Volume Shadow Copy has been made.
749 Console commands can be specified within a RunScript by using:
750 {\bf Console = \lt{}command\gt{}}, however, this command has not been
751 carefully tested and debugged and is known to easily crash the Director.
752 We would appreciate feedback. Due to the recursive nature of this command, we
753 may remove it before the final release.
755 \subsection{Status Enhancements}
756 The bconsole {\bf status dir} output has been enhanced to indicate
757 Storage daemon job spooling and despooling activity.
759 \subsection{Connect Timeout}
760 The default connect timeout to the File
761 daemon has been set to 3 minutes. Previously it was 30 minutes.
763 \subsection{ftruncate for NFS Volumes}
764 If you write to a Volume mounted by NFS (say on a local file server),
765 in previous Bacula versions, when the Volume was recycled, it was not
766 properly truncated because NFS does not implement ftruncate (file
767 truncate). This is now corrected in the new version because we have
768 written code (actually a kind user) that deletes and recreates the Volume,
769 thus accomplishing the same thing as a truncate.
771 \subsection{Support for Ubuntu}
772 The new version of Bacula now recognizes the Ubuntu (and Kubuntu)
773 version of Linux, and thus now provides correct autostart routines.
774 Since Ubuntu officially supports Bacula, you can also obtain any
775 recent release of Bacula from the Ubuntu repositories.
777 \subsection{Recycle Pool = \lt{}pool-name\gt{}}
778 The new \textbf{RecyclePool} directive defines to which pool the Volume will
779 be placed (moved) when it is recycled. Without this directive, a Volume will
780 remain in the same pool when it is recycled. With this directive, it can be
781 moved automatically to any existing pool during a recycle. This directive is
782 probably most useful when defined in the Scratch pool, so that volumes will
783 be recycled back into the Scratch pool.
785 \subsection{FD Version}
786 The File daemon to Director protocol now includes a version
787 number, which although there is no visible change for users,
788 will help us in future versions automatically determine
789 if a File daemon is not compatible.
791 \subsection{Max Run Sched Time = \lt{}time-period-in-seconds\gt{}}
792 The time specifies the maximum allowed time that a job may run, counted from
793 when the job was scheduled. This can be useful to prevent jobs from running
794 during working hours. We can see it like \texttt{Max Start Delay + Max Run
797 \subsection{Max Wait Time = \lt{}time-period-in-seconds\gt{}}
799 Previous \textbf{MaxWaitTime} directives aren't working as expected, instead
800 of checking the maximum allowed time that a job may block for a resource,
801 those directives worked like \textbf{MaxRunTime}. Some users are reporting to
802 use \textbf{Incr/Diff/Full Max Wait Time} to control the maximum run time of
803 their job depending on the level. Now, they have to use
804 \textbf{Incr/Diff/Full Max Run Time}. \textbf{Incr/Diff/Full Max Wait Time}
805 directives are now deprecated.
807 \subsection{Incremental|Differential Max Wait Time = \lt{}time-period-in-seconds\gt{}}
808 Theses directives have been deprecated in favor of
809 \texttt{Incremental|Differential Max Run Time}.
811 \subsection{Max Run Time directives}
812 Using \textbf{Full/Diff/Incr Max Run Time}, it's now possible to specify the
813 maximum allowed time that a job can run depending on the level.
815 \addcontentsline{lof}{figure}{Job time control directives}
816 \includegraphics{\idir different_time.eps}
818 \subsection{Statistics Enhancements}
819 If you (or probably your boss) want to have statistics on your backups to
820 provide some \textit{Service Level Agreement} indicators, you could use a few
821 SQL queries on the Job table to report how many:
825 \item jobs have been successful
826 \item files have been backed up
830 However, these statistics are accurate only if your job retention is greater
831 than your statistics period. Ie, if jobs are purged from the catalog, you won't
834 Now, you can use the \textbf{update stats [days=num]} console command to fill
835 the JobStat table with new Job records. If you want to be sure to take in
836 account only \textbf{good jobs}, ie if one of your important job has failed but
837 you have fixed the problem and restarted it on time, you probably want to
838 delete the first \textit{bad} job record and keep only the successful one. For
839 that simply let your staff do the job, and update JobStat table after two or
840 three days depending on your organization using the \textbf{[days=num]} option.
842 These statistics records aren't used for restoring, but mainly for
843 capacity planning, billings, etc.
845 The Bweb interface provides a statistics module that can use this feature. You
846 can also use tools like Talend or extract information by yourself.
848 The {\textbf Statistics Retention = \lt{}time\gt{}} director directive defines
849 the length of time that Bacula will keep statistics job records in the Catalog
850 database after the Job End time. (In \texttt{JobStat} table) When this time
851 period expires, and if user runs \texttt{prune stats} command, Bacula will
852 prune (remove) Job records that are older than the specified period.
854 You can use the following Job resource in your nightly \textbf{BackupCatalog}
855 job to maintain statistics.
861 Console = "update stats days=3"
862 Console = "prune stats yes"
869 \subsection{SpoolSize = \lt{}size-specification-in-bytes\gt{}}
870 A new job directive permits to specify the spool size per job. This is used
871 in advanced job tunning. {\bf SpoolSize={\it bytes}}
874 \section{Building Bacula Plugins}
875 There is currently one sample program {\bf example-plugin-fd.c} and
876 one working plugin {\bf bpipe-fd.c} that can be found in the Bacula
877 {\bf src/plugins/fd} directory. Both are built with the following:
881 ./configure <your-options>
889 After building Bacula and changing into the src/plugins/fd directory,
890 the {\bf make} command will build the {\bf bpipe-fd.so} plugin, which
891 is a very useful and working program.
893 The {\bf make test} command will build the {\bf example-plugin-fd.so}
894 plugin and a binary named {\bf main}, which is build from the source
895 code located in {\bf src/filed/fd\_plugins.c}.
897 If you execute {\bf ./main}, it will load and run the example-plugin-fd
898 plugin simulating a small number of the calling sequences that Bacula uses
899 in calling a real plugin. This allows you to do initial testing of
900 your plugin prior to trying it with Bacula.
902 You can get a good idea of how to write your own plugin by first
903 studying the example-plugin-fd, and actually running it. Then
904 it can also be instructive to read the bpipe-fd.c code as it is
905 a real plugin, which is still rather simple and small.
907 When actually writing your own plugin, you may use the example-plugin-fd.c
908 code as a template for your code.
914 \chapter{Bacula FD Plugin API}
915 To write a Bacula plugin, you create a dynamic shared object
916 program (or dll on Win32) with a particular name and two
917 exported entry points, place it in the {\bf Plugins Directory}, which is defined in the
918 {\bf bacula-fd.conf} file in the {\bf Client} resource, and when the FD
919 starts, it will load all the plugins that end with {\bf -fd.so} (or {\bf -fd.dll}
920 on Win32) found in that directory.
922 \section{Normal vs Command Plugins}
923 In general, there are two ways that plugins are called. The first way,
924 is when a particular event is detected in Bacula, it will transfer control
925 to each plugin that is loaded in turn informing the plugin of the event.
926 This is very similar to how a {\bf RunScript} works, and the events are very similar.
927 Once the plugin gets control, it can interact with Bacula by getting and
928 setting Bacula variables. In this way, it behaves much like a RunScript.
929 Currently very few Bacula variables are defined, but they will be implemented
930 as the need arrises, and it is very extensible.
932 We plan to have plugins register to receive events that they normally would
933 not receive, such as an event for each file examined for backup or restore.
934 This feature is not yet implemented.
936 The second type of plugin, which is more useful and fully implemented
937 in the current version is what we call a command plugin. As with all
938 plugins, it gets notified of important events as noted above (details described below),
939 but in addition, this kind of plugin can accept a command line, which
943 Plugin = <command-string>
946 directive that is placed in the Include section of a FileSet and is very
947 similar to the "File = " directive. When this Plugin directive is encountered
948 by Bacula during backup, it passes the "command" part of the Plugin directive
949 only to the plugin that is explicitly named in the first field of that command string.
950 This allows that plugin to backup any file or files on the system that it wants. It can
951 even create "virtual files" in the catalog that contain data to be restored but do
952 not necessarily correspond to actual files on the filesystem.
954 The important features of the command plugin entry points are:
956 \item It is triggered by a "Plugin =" directive in the FileSet
957 \item Only a single plugin is called that is named on the "Plugin =" directive.
958 \item The full command string after the "Plugin =" is passed to the plugin
959 so that it can be told what to backup/restore.
963 \section{Loading Plugins}
964 Once the File daemon loads the plugins, it asks the OS for the
965 two entry points (loadPlugin and unloadPlugin) then calls the
966 {\bf loadPlugin} entry point (see below).
968 Bacula passes information to the plugin through this call and it gets
969 back information that it needs to use the plugin. Later, Bacula
970 will call particular functions that are defined by the
971 {\bf loadPlugin} interface.
973 When Bacula is finished with the plugin
974 (when Bacula is going to exit), it will call the {\bf unloadPlugin}
977 The two entry points are:
980 bRC loadPlugin(bInfo *lbinfo, bFuncs *lbfuncs, pInfo **pinfo, pFuncs **pfuncs)
987 both these external entry points to the shared object are defined as C entry points
988 to avoid name mangling complications with C++. However, the shared object
989 can actually be written in any language (preferrably C or C++) providing that it
990 follows C language calling conventions.
992 The definitions for {\bf bRC} and the arguments are {\bf
993 src/filed/fd-plugins.h} and so this header file needs to be included in
994 your plugin. It along with {\bf src/lib/plugins.h} define basically the whole
995 plugin interface. Within this header file, it includes the following
999 #include <sys/types.h>
1001 #include "bc_types.h"
1002 #include "lib/plugins.h"
1003 #include <sys/stat.h>
1006 Aside from the {\bf bc\_types.h} and {\bf confit.h} headers, the plugin definition uses the
1007 minimum code from Bacula. The bc\_types.h file is required to ensure that
1008 the data type defintions in arguments correspond to the Bacula core code.
1010 The return codes are defined as:
1013 bRC_OK = 0, /* OK */
1014 bRC_Stop = 1, /* Stop calling other plugins */
1015 bRC_Error = 2, /* Some kind of error */
1016 bRC_More = 3, /* More files to backup */
1021 At a future point in time, we hope to make the Bacula libbac.a into a
1022 shared object so that the plugin can use much more of Bacula's
1023 infrastructure, but for this first cut, we have tried to minimize the
1024 dependence on Bacula.
1026 \section{loadPlugin}
1027 As previously mentioned, the {\bf loadPlugin} entry point in the plugin
1028 is called immediately after Bacula loads the plugin when the File daemon
1029 itself is first starting. This entry point is only called once during the
1030 execution of the File daemon. In calling the
1031 plugin, the first two arguments are information from Bacula that
1032 is passed to the plugin, and the last two arguments are information
1033 about the plugin that the plugin must return to Bacula. The call is:
1036 bRC loadPlugin(bInfo *lbinfo, bFuncs *lbfuncs, pInfo **pinfo, pFuncs **pfuncs)
1039 and the arguments are:
1043 This is information about Bacula in general. Currently, the only value
1044 defined in the bInfo structure is the version, which is the Bacula plugin
1045 interface version, currently defined as 1. The {\bf size} is set to the
1046 byte size of the structure. The exact definition of the bInfo structure
1047 as of this writing is:
1050 typedef struct s_baculaInfo {
1057 The bFuncs structure defines the callback entry points within Bacula
1058 that the plugin can use register events, get Bacula values, set
1059 Bacula values, and send messages to the Job output or debug output.
1061 The exact definition as of this writing is:
1063 typedef struct s_baculaFuncs {
1066 bRC (*registerBaculaEvents)(bpContext *ctx, ...);
1067 bRC (*getBaculaValue)(bpContext *ctx, bVariable var, void *value);
1068 bRC (*setBaculaValue)(bpContext *ctx, bVariable var, void *value);
1069 bRC (*JobMessage)(bpContext *ctx, const char *file, int line,
1070 int type, time_t mtime, const char *fmt, ...);
1071 bRC (*DebugMessage)(bpContext *ctx, const char *file, int line,
1072 int level, const char *fmt, ...);
1073 void *(*malloc)(bpContext *ctx, const char *file, int line,
1075 void (*free)(bpContext *ctx, const char *file, int line, void *mem);
1079 We will discuss these entry points and how to use them a bit later when
1080 describing the plugin code.
1084 When the loadPlugin entry point is called, the plugin must initialize
1085 an information structure about the plugin and return a pointer to
1086 this structure to Bacula.
1088 The exact definition as of this writing is:
1091 typedef struct s_pluginInfo {
1094 const char *plugin_magic;
1095 const char *plugin_license;
1096 const char *plugin_author;
1097 const char *plugin_date;
1098 const char *plugin_version;
1099 const char *plugin_description;
1105 \item [version] is the current Bacula defined plugin interface version, currently
1106 set to 1. If the interface version differs from the current version of
1107 Bacula, the plugin will not be run (not yet implemented).
1108 \item [plugin\_magic] is a pointer to the text string "*FDPluginData*", a
1109 sort of sanity check. If this value is not specified, the plugin
1110 will not be run (not yet implemented).
1111 \item [plugin\_license] is a pointer to a text string that describes the
1112 plugin license. Bacula will only accept compatible licenses (not yet
1114 \item [plugin\_author] is a pointer to the text name of the author of the program.
1115 This string can be anything but is generally the author's name.
1116 \item [plugin\_date] is the pointer text string containing the date of the plugin.
1117 This string can be anything but is generally some human readable form of
1119 \item [plugin\_version] is a pointer to a text string containing the version of
1120 the plugin. The contents are determined by the plugin writer.
1121 \item [plugin\_description] is a pointer to a string describing what the
1122 plugin does. The contents are determined by the plugin writer.
1125 The pInfo structure must be defined in static memory because Bacula does not
1126 copy it and may refer to the values at any time while the plugin is
1127 loaded. All values must be supplied or the plugin will not run (not yet
1128 implemented). All text strings must be either ASCII or UTF-8 strings that
1129 are terminated with a zero byte.
1132 When the loadPlugin entry point is called, the plugin must initialize
1133 an entry point structure about the plugin and return a pointer to
1134 this structure to Bacula. This structure contains pointer to each
1135 of the entry points that the plugin must provide for Bacula. When
1136 Bacula is actually running the plugin, it will call the defined
1137 entry points at particular times. All entry points must be defined.
1139 The pFuncs structure must be defined in static memory because Bacula does not
1140 copy it and may refer to the values at any time while the plugin is
1143 The exact definition as of this writing is:
1146 typedef struct s_pluginFuncs {
1149 bRC (*newPlugin)(bpContext *ctx);
1150 bRC (*freePlugin)(bpContext *ctx);
1151 bRC (*getPluginValue)(bpContext *ctx, pVariable var, void *value);
1152 bRC (*setPluginValue)(bpContext *ctx, pVariable var, void *value);
1153 bRC (*handlePluginEvent)(bpContext *ctx, bEvent *event, void *value);
1154 bRC (*startBackupFile)(bpContext *ctx, struct save_pkt *sp);
1155 bRC (*endBackupFile)(bpContext *ctx);
1156 bRC (*startRestoreFile)(bpContext *ctx, const char *cmd);
1157 bRC (*endRestoreFile)(bpContext *ctx);
1158 bRC (*pluginIO)(bpContext *ctx, struct io_pkt *io);
1159 bRC (*createFile)(bpContext *ctx, struct restore_pkt *rp);
1160 bRC (*setFileAttributes)(bpContext *ctx, struct restore_pkt *rp);
1164 The details of the entry points will be presented in
1165 separate sections below.
1169 \item [size] is the byte size of the structure.
1170 \item [version] is the plugin interface version currently set to 1.
1173 Sample code for loadPlugin:
1175 bfuncs = lbfuncs; /* set Bacula funct pointers */
1177 *pinfo = &pluginInfo; /* return pointer to our info */
1178 *pfuncs = &pluginFuncs; /* return pointer to our functions */
1183 where pluginInfo and pluginFuncs are statically defined structures.
1184 See bpipe-fd.c for details.
1190 \section{Plugin Entry Points}
1191 This section will describe each of the entry points (subroutines) within
1192 the plugin that the plugin must provide for Bacula, when they are called
1193 and their arguments. As noted above, pointers to these subroutines are
1194 passed back to Bacula in the pFuncs structure when Bacula calls the
1195 loadPlugin() externally defined entry point.
1197 \subsection{newPlugin(bpContext *ctx)}
1198 This is the entry point that Bacula will call
1199 when a new "instance" of the plugin is created. This typically
1200 happens at the beginning of a Job. If 10 Jobs are running
1201 simultaneously, there will be at least 10 instances of the
1204 The bpContext structure will be passed to the plugin, and
1205 during this call, if the plugin needs to have its private
1206 working storage that is associated with the particular
1207 instance of the plugin, it should create it from the heap
1208 (malloc the memory) and store a pointer to
1209 its private working storage in the {\bf pContext} variable.
1210 Note: since Bacula is a multi-threaded program, you must not
1211 keep any variable data in your plugin unless it is truely meant
1212 to apply globally to the whole plugin. In addition, you must
1213 be aware that except the first and last call to the plugin
1214 (loadPlugin and unloadPlugin) all the other calls will be
1215 made by threads that correspond to a Bacula job. The
1216 bpContext that will be passed for each thread will remain the
1217 same throughout the Job thus you can keep your privat Job specific
1218 data in it ({\bf bContext}).
1221 typedef struct s_bpContext {
1222 void *pContext; /* Plugin private context */
1223 void *bContext; /* Bacula private context */
1228 This context pointer will be passed as the first argument to all
1229 the entry points that Bacula calls within the plugin. Needless
1230 to say, the plugin should not change the bContext variable, which
1231 is Bacula's private context pointer for this instance (Job) of this
1234 \subsection{freePlugin(bpContext *ctx)}
1235 This entry point is called when the
1236 this instance of the plugin is no longer needed (the Job is
1237 ending), and the plugin should release all memory it may
1238 have allocated for this particular instance (Job) i.e. the pContext.
1239 This is not the final termination
1240 of the plugin signaled by a call to {\bf unloadPlugin}.
1241 Any other instances (Job) will
1242 continue to run, and the entry point {\bf newPlugin} may be called
1243 again if other jobs start.
1245 \subsection{getPluginValue(bpContext *ctx, pVariable var, void *value)}
1246 Bacula will call this entry point to get
1247 a value from the plugin. This entry point is currently not called.
1249 \subsection{setPluginValue(bpContext *ctx, pVariable var, void *value)}
1250 Bacula will call this entry point to set
1251 a value in the plugin. This entry point is currently not called.
1253 \subsection{handlePluginEvent(bpContext *ctx, bEvent *event, void *value)}
1254 This entry point is called when Bacula
1255 encounters certain events (discussed below). This is, in fact, the
1256 main way that most plugins get control when a Job runs and how
1257 they know what is happening in the job. It can be likened to the
1258 {\bf RunScript} feature that calls external programs and scripts,
1259 and is very similar to the Bacula Python interface.
1260 When the plugin is called, Bacula passes it the pointer to an event
1261 structure (bEvent), which currently has one item, the eventType:
1264 typedef struct s_bEvent {
1269 which defines what event has been triggered, and for each event,
1270 Bacula will pass a pointer to a value associated with that event.
1271 If no value is associated with a particular event, Bacula will
1272 pass a NULL pointer, so the plugin must be careful to always check
1273 value pointer prior to dereferencing it.
1275 The current list of events are:
1281 bEventStartBackupJob = 3,
1282 bEventEndBackupJob = 4,
1283 bEventStartRestoreJob = 5,
1284 bEventEndRestoreJob = 6,
1285 bEventStartVerifyJob = 7,
1286 bEventEndVerifyJob = 8,
1287 bEventBackupCommand = 9,
1288 bEventRestoreCommand = 10,
1295 Most of the above are self-explanatory.
1298 \item [bEventJobStart] is called whenever a Job starts. The value
1299 passed is a pointer to a string that contains: "Jobid=nnn
1300 Job=job-name". Where nnn will be replaced by the JobId and job-name
1301 will be replaced by the Job name. The variable is temporary so if you
1302 need the values, you must copy them.
1304 \item [bEventJobEnd] is called whenever a Job ends. No value is passed.
1306 \item [bEventStartBackupJob] is called when a Backup Job begins. No value
1309 \item [bEventEndBackupJob] is called when a Backup Job ends. No value is
1312 \item [bEventStartRestoreJob] is called when a Restore Job starts. No value
1315 \item [bEventEndRestoreJob] is called when a Restore Job ends. No value is
1318 \item [bEventStartVerifyJob] is called when a Verify Job starts. No value
1321 \item [bEventEndVerifyJob] is called when a Verify Job ends. No value
1324 \item [bEventBackupCommand] is called prior to the bEventStartBackupJob and
1325 the plugin is passed the command string (everything after the equal sign
1326 in "Plugin =" as the value.
1328 Note, if you intend to backup a file, this is an important first point to
1329 write code that copies the command string passed into your pContext area
1330 so that you will know that a backup is being performed and you will know
1331 the full contents of the "Plugin =" command (i.e. what to backup and
1332 what virtual filename the user wants to call it.
1334 \item [bEventRestoreCommand] is called prior to the bEventStartRestoreJob and
1335 the plugin is passed the command string (everything after the equal sign
1336 in "Plugin =" as the value.
1338 See the notes above concerning backup and the command string. This is the
1339 point at which Bacula passes you the original command string that was
1340 specified during the backup, so you will want to save it in your pContext
1341 area for later use when Bacula calls the plugin again.
1343 \item [bEventLevel] is called when the level is set for a new Job. The value
1344 is a 32 bit integer stored in the void*, which represents the Job Level code.
1346 \item [bEventSince] is called when the since time is set for a new Job. The
1347 value is a time\_t time at which the last job was run.
1350 During each of the above calls, the plugin receives either no specific value or
1351 only one value, which in some cases may not be sufficient. However, knowing the
1352 context of the event, the plugin can call back to the Bacula entry points it
1353 was passed during the {\bf loadPlugin} call and get to a number of Bacula variables.
1354 (at the current time few Bacula variables are implemented, but it easily extended
1355 at a future time and as needs require).
1357 \subsection{startBackupFile(bpContext *ctx, struct save\_pkt *sp)}
1358 This entry point is called only if your plugin is a command plugin, and
1359 it is called when Bacula encounters the "Plugin = " directive in
1360 the Include section of the FileSet.
1361 Called when beginning the backup of a file. Here Bacula provides you
1362 with a pointer to the {\bf save\_pkt} structure and you must fill in
1363 this packet with the "attribute" data of the file.
1367 int32_t pkt_size; /* size of this packet */
1368 char *fname; /* Full path and filename */
1369 char *link; /* Link name if any */
1370 struct stat statp; /* System stat() packet for file */
1371 int32_t type; /* FT_xx for this file */
1372 uint32_t flags; /* Bacula internal flags */
1373 bool portable; /* set if data format is portable */
1374 char *cmd; /* command */
1375 int32_t pkt_end; /* end packet sentinel */
1379 The second argument is a pointer to the {\bf save\_pkt} structure for the file
1380 to be backed up. The plugin is responsible for filling in all the fields
1381 of the {\bf save\_pkt}. If you are backing up
1382 a real file, then generally, the statp structure can be filled in by doing
1383 a {\bf stat} system call on the file.
1385 If you are backing up a database or
1386 something that is more complex, you might want to create a virtual file.
1387 That is a file that does not actually exist on the filesystem, but represents
1388 say an object that you are backing up. In that case, you need to ensure
1389 that the {\bf fname} string that you pass back is unique so that it
1390 does not conflict with a real file on the system, and you need to
1391 artifically create values in the statp packet.
1393 Example programs such as {\bf bpipe-fd.c} show how to set these fields.
1394 You must take care not to store pointers the stack in the pointer fields such
1395 as fname and link, because when you return from your function, your stack entries
1396 will be destroyed. The solution in that case is to malloc() and return the pointer
1397 to it. In order to not have memory leaks, you should store a pointer to all memory
1398 allocated in your pContext structure so that in subsequent calls or at termination,
1399 you can release it back to the system.
1401 Once the backup has begun, Bacula will call your plugin at the {\bf pluginIO}
1402 entry point to "read" the data to be backed up. Please see the {\bf bpipe-fd.c}
1403 plugin for how to do I/O.
1405 Example of filling in the save\_pkt as used in bpipe-fd.c:
1408 struct plugin_ctx *p_ctx = (struct plugin_ctx *)ctx->pContext;
1409 time_t now = time(NULL);
1410 sp->fname = p_ctx->fname;
1411 sp->statp.st_mode = 0700 | S_IFREG;
1412 sp->statp.st_ctime = now;
1413 sp->statp.st_mtime = now;
1414 sp->statp.st_atime = now;
1415 sp->statp.st_size = -1;
1416 sp->statp.st_blksize = 4096;
1417 sp->statp.st_blocks = 1;
1418 p_ctx->backup = true;
1422 Note: the filename to be created has already been created from the
1423 command string previously sent to the plugin and is in the plugin
1424 context (p\_ctx->fname) and is a malloc()ed string. This example
1425 creates a regular file (S\_IFREG), with various fields being created.
1427 In general, the sequence of commands issued from Bacula to the plugin
1428 to do a backup while processing the "Plugin = " directive are:
1431 \item generate a bEventBackupCommand event to the specified plugin
1432 and pass it the command string.
1433 \item make a startPluginBackup call to the plugin, which
1434 fills in the data needed in save\_pkt to save as the file
1435 attributes and to put on the Volume and in the catalog.
1436 \item call Bacula's internal save\_file() subroutine to save the specified
1437 file. The plugin will then be called at pluginIO() to "open"
1438 the file, and then to read the file data.
1439 Note, if you are dealing with a virtual file, the "open" operation
1440 is something the plugin does internally and it doesn't necessarily
1441 mean opening a file on the filesystem. For example in the case of
1442 the bpipe-fd.c program, it initiates a pipe to the requested program.
1443 Finally when the plugin signals to Bacula that all the data was read,
1444 Bacula will call the plugin with the "close" pluginIO() function.
1448 \subsection{endBackupFile(bpContext *ctx)}
1449 Called at the end of backing up a file for a command plugin. If the plugin's work
1450 is done, it should return bRC\_OK. If the plugin wishes to create another
1451 file and back it up, then it must return bRC\_More (not yet implemented).
1452 This is probably a good time to release any malloc()ed memory you used to
1453 pass back filenames.
1455 \subsection{startRestoreFile(bpContext *ctx, const char *cmd)}
1456 Called when the first record is read from the Volume that was
1457 previously written by the command plugin.
1459 \subsection{createFile(bpContext *ctx, struct restore\_pkt *rp)}
1460 Called for a command plugin to create a file during a Restore job before
1462 This entry point is called before any I/O is done on the file. After
1463 this call, Bacula will call pluginIO() to open the file for write.
1466 restore\_pkt is passed to the plugin and is based on the data that was
1467 originally given by the plugin during the backup and the current user
1468 restore settings (e.g. where, RegexWhere, replace). This allows the
1469 plugin to first create a file (if necessary) so that the data can
1470 be transmitted to it. The next call to the plugin will be a
1471 pluginIO command with a request to open the file write-only.
1473 This call must return one of the following values:
1477 CF_SKIP = 1, /* skip file (not newer or something) */
1478 CF_ERROR, /* error creating file */
1479 CF_EXTRACT, /* file created, data to extract */
1480 CF_CREATED /* file created, no data to extract */
1484 in the restore\_pkt value {\bf create\_status}. For a normal file,
1485 unless there is an error, you must return {\bf CF\_EXTRACT}.
1489 struct restore_pkt {
1490 int32_t pkt_size; /* size of this packet */
1491 int32_t stream; /* attribute stream id */
1492 int32_t data_stream; /* id of data stream to follow */
1493 int32_t type; /* file type FT */
1494 int32_t file_index; /* file index */
1495 int32_t LinkFI; /* file index to data if hard link */
1496 uid_t uid; /* userid */
1497 struct stat statp; /* decoded stat packet */
1498 const char *attrEx; /* extended attributes if any */
1499 const char *ofname; /* output filename */
1500 const char *olname; /* output link name */
1501 const char *where; /* where */
1502 const char *RegexWhere; /* regex where */
1503 int replace; /* replace flag */
1504 int create_status; /* status from createFile() */
1505 int32_t pkt_end; /* end packet sentinel */
1510 Typical code to create a regular file would be the following:
1513 struct plugin_ctx *p_ctx = (struct plugin_ctx *)ctx->pContext;
1514 time_t now = time(NULL);
1515 sp->fname = p_ctx->fname; /* set the full path/filename I want to create */
1517 sp->statp.st_mode = 0700 | S_IFREG;
1518 sp->statp.st_ctime = now;
1519 sp->statp.st_mtime = now;
1520 sp->statp.st_atime = now;
1521 sp->statp.st_size = -1;
1522 sp->statp.st_blksize = 4096;
1523 sp->statp.st_blocks = 1;
1527 This will create a virtual file. If you are creating a file that actually
1528 exists, you will most likely want to fill the statp packet using the
1531 Creating a directory is similar, but requires a few extra steps:
1534 struct plugin_ctx *p_ctx = (struct plugin_ctx *)ctx->pContext;
1535 time_t now = time(NULL);
1536 sp->fname = p_ctx->fname; /* set the full path I want to create */
1537 sp->link = xxx; where xxx is p_ctx->fname with a trailing forward slash
1538 sp->type = FT_DIREND
1539 sp->statp.st_mode = 0700 | S_IFDIR;
1540 sp->statp.st_ctime = now;
1541 sp->statp.st_mtime = now;
1542 sp->statp.st_atime = now;
1543 sp->statp.st_size = -1;
1544 sp->statp.st_blksize = 4096;
1545 sp->statp.st_blocks = 1;
1549 The link field must be set with the full cononical path name, which always
1550 ends with a forward slash. If you do not terminate it with a forward slash,
1551 you will surely have problems later.
1553 As with the example that creates a file, if you are backing up a real
1554 directory, you will want to do an stat() on the directory.
1556 Note, if you want the directory permissions and times to be correctly
1557 restored, you must create the directory {\bf after} all the file directories
1558 have been sent to Bacula. That allows the restore process to restore all the
1559 files in a directory using default directory options, then at the end, restore
1560 the directory permissions. If you do it the other way around, each time you
1561 restore a file, the OS will modify the time values for the directory entry.
1563 \subsection{setFileAttributes(bpContext *ctx, struct restore\_pkt *rp)}
1564 This is call not yet implemented. Called for a command plugin.
1566 See the definition of {\bf restre\_pkt} in the above section.
1568 \subsection{endRestoreFile(bpContext *ctx)}
1569 Called when a command plugin is done restoring a file.
1571 \subsection{pluginIO(bpContext *ctx, struct io\_pkt *io)}
1572 Called to do the input (backup) or output (restore) of data from or to a
1573 file for a command plugin. These routines simulate the Unix read(), write(), open(), close(),
1574 and lseek() I/O calls, and the arguments are passed in the packet and
1575 the return values are also placed in the packet. In addition for Win32
1576 systems the plugin must return two additional values (described below).
1588 int32_t pkt_size; /* Size of this packet */
1589 int32_t func; /* Function code */
1590 int32_t count; /* read/write count */
1591 mode_t mode; /* permissions for created files */
1592 int32_t flags; /* Open flags */
1593 char *buf; /* read/write buffer */
1594 const char *fname; /* open filename */
1595 int32_t status; /* return status */
1596 int32_t io_errno; /* errno code */
1597 int32_t lerror; /* Win32 error code */
1598 int32_t whence; /* lseek argument */
1599 boffset_t offset; /* lseek argument */
1600 bool win32; /* Win32 GetLastError returned */
1601 int32_t pkt_end; /* end packet sentinel */
1605 The particular Unix function being simulated is indicated by the {\bf func},
1606 which will have one of the IO\_OPEN, IO\_READ, ... codes listed above.
1607 The status code that would be returned from a Unix call is returned in
1608 {\bf status} for IO\_OPEN, IO\_CLOSE, IO\_READ, and IO\_WRITE. The return value for
1609 IO\_SEEK is returned in {\bf offset} which in general is a 64 bit value.
1611 When there is an error on Unix systems, you must always set io\_error, and
1612 on a Win32 system, you must always set win32, and the returned value from
1613 the OS call GetLastError() in lerror.
1615 For all except IO\_SEEK, {\bf status} is the return result. In general it is
1616 a positive integer unless there is an error in which case it is -1.
1618 The following describes each call and what you get and what you
1623 You will be passed fname, mode, and flags.
1624 You must set on return: status, and if there is a Unix error
1625 io\_errno must be set to the errno value, and if there is a
1626 Win32 error win32 and lerror.
1629 You will be passed: count, and buf (buffer of size count).
1630 You must set on return: status to the number of bytes
1631 read into the buffer (buf) or -1 on an error,
1632 and if there is a Unix error
1633 io\_errno must be set to the errno value, and if there is a
1634 Win32 error, win32 and lerror must be set.
1637 You will be passed: count, and buf (buffer of size count).
1638 You must set on return: status to the number of bytes
1639 written from the buffer (buf) or -1 on an error,
1640 and if there is a Unix error
1641 io\_errno must be set to the errno value, and if there is a
1642 Win32 error, win32 and lerror must be set.
1645 Nothing will be passed to you. On return you must set
1646 status to 0 on success and -1 on failure. If there is a Unix error
1647 io\_errno must be set to the errno value, and if there is a
1648 Win32 error, win32 and lerror must be set.
1651 You will be passed: offset, and whence. offset is a 64 bit value
1652 and is the position to seek to relative to whence. whence is one
1653 of the following SEEK\_SET, SEEK\_CUR, or SEEK\_END indicating to
1654 either to seek to an absolute possition, relative to the current
1655 position or relative to the end of the file.
1656 You must pass back in offset the absolute location to which you
1657 seeked. If there is an error, offset should be set to -1.
1658 If there is a Unix error
1659 io\_errno must be set to the errno value, and if there is a
1660 Win32 error, win32 and lerror must be set.
1662 Note: Bacula will call IO\_SEEK only when writing a sparse file.