4 \chapter{The Current State of Bacula}
6 \index[general]{Current state of Bacula}
8 In other words, what is and what is not currently implemented and functional.
10 \section{What is Implemented}
11 \index[general]{Implemented!What}
12 \index[general]{What is Implemented}
17 \item Network backup/restore with centralized Director.
18 \item Internal scheduler for automatic
19 \ilink{Job}{JobDef} (cf. \S\bsysref{JobDef}) execution.
20 \item Scheduling of multiple Jobs at the same time.
21 \item You may run one Job at a time or multiple simultaneous Jobs
22 (sometimes called multiplexing).
23 \item Job sequencing using priorities.
24 \item \ilink{Console}{UADef} interface to the Director allowing complete
25 control. A shell, Qt4 GUI, wxWidgets GUI and Web versions of
26 the Console program are available. Note, the Qt4 GUI program called
27 the Bacula Administration tool or bat, offers many additional
28 features over the shell program.
33 \item Verification of files previously cataloged, permitting a Tripwire like
34 capability (system break-in detection).
35 \item CRAM-MD5 password authentication between each component (daemon).
37 \ilink{TLS (SSL) communications encryption}{CommEncryption} between each
40 \ilink{Data (on Volume) encryption}{DataEncryption}
41 on a Client by Client basis.
42 \item Computation of MD5 or SHA1 signatures of the file data if requested.
46 \item Restore Features
48 \item Restore of one or more files selected interactively either for the
49 current backup or a backup prior to a specified time and date.
50 \item Restore of a complete system starting from bare metal. This is mostly
51 automated for Linux systems and partially automated for Solaris. See
52 \ilink{Disaster Recovery Using Bacula}{RescueChapter}. This is also
53 reported to work on Win2K/XP systems.
54 \item Listing and Restoration of files using stand-alone {\bf bls} and {\bf
55 bextract} tool programs. Among other things, this permits extraction of
56 files when Bacula and/or the catalog are not available. Note, the
57 recommended way to restore files is using the restore command in the
58 Console. These programs are designed for use as a last resort.
59 \item Ability to restore the catalog database rapidly by using bootstrap
60 files (previously saved).
61 \item Ability to recreate the catalog database by scanning backup Volumes
62 using the {\bf bscan} program.
67 \item Catalog database facility for remembering Volumes, Pools, Jobs, and
69 \item Support for MySQL, PostgreSQL, and SQLite Catalog databases.
70 \item User extensible queries to the MySQL, PostgreSQL and SQLite databases.
73 \item Advanced Volume and Pool Management
75 \item Labeled Volumes, preventing accidental overwriting (at least by
77 \item Any number of Jobs and Clients can be backed up to a single Volume.
78 That is, you can backup and restore Linux, Unix, Sun, and Windows machines to
80 \item Multi-volume saves. When a Volume is full, {\bf Bacula} automatically
81 requests the next Volume and continues the backup.
83 \ilink{Pool and Volume}{PoolResource} library management
84 providing Volume flexibility (e.g. monthly, weekly, daily Volume sets, Volume
85 sets segregated by Client, ...).
86 \item Machine independent Volume data format. Linux, Solaris, and Windows
87 clients can all be backed up to the same Volume if desired.
88 \item The Volume data format is upwards compatible so that old Volumes
91 \ilink{message}{MessagesChapter} handler including routing
92 of messages from any daemon back to the Director and automatic email
94 \item Data spooling to disk during backup with subsequent write to tape from
95 the spooled disk files. This prevents tape "shoe shine" during
96 Incremental/Differential backups.
99 \item Advanced Support for most Storage Devices
101 \item Autochanger support using a simple shell interface that can interface
102 to virtually any autoloader program. A script for {\bf mtx} is provided.
103 \item Support for autochanger barcodes -- automatic tape labeling from
105 \item Automatic support for multiple autochanger magazines either using
106 barcodes or by reading the tapes.
107 \item Support for multiple drive autochangers.
108 \item Raw device backup/restore. Restore must be to the same device.
109 \item All Volume blocks (approximately 64K bytes) contain a data checksum.
110 \item Migration support -- move data from one Pool to another or
111 one Volume to another.
112 \item Supports writing to DVD.
115 \item Multi-Operating System Support
117 \item Programmed to handle arbitrarily long filenames and messages.
118 \item GZIP compression on a file by file basis done by the Client program if
119 requested before network transit.
120 \item Saves and restores POSIX ACLs and Extended Attributes on most OSes if
122 \item Access control lists for Consoles that permit restricting user access
124 \item Support for save/restore of files larger than 2GB.
125 \item Support for 64 bit machines, e.g. amd64, Sparc.
126 \item Support ANSI and IBM tape labels.
127 \item Support for Unicode filenames (e.g. Chinese) on Win32 machines
128 \item Consistent backup of open files on Win32 systems (WinXP, Win2003,
130 but not Win2000, using Volume Shadow Copy (VSS).
131 \item Support for path/filename lengths of up to 64K on Win32 machines
132 (unlimited on Unix/Linux machines).
137 \item Multi-threaded implementation.
138 \item A comprehensive and extensible
139 \ilink{configuration file}{DirectorChapter} for each daemon.
143 \section{Advantages Over Other Backup Programs}
144 \index[general]{Advantages of Bacula Over Other Backup Programs }
145 \index[general]{Programs!Advantages of Bacula Over Other Backup }
148 \item Since there is a client for each machine, you can backup
149 and restore clients of any type ensuring that all attributes
150 of files are properly saved and restored.
151 \item It is also possible to backup clients without any client
152 software by using NFS or Samba. However, if possible, we
153 recommend running a Client File daemon on each machine to be
155 \item Bacula handles multi-volume backups.
156 \item A full comprehensive SQL standard database of all files backed up. This
157 permits online viewing of files saved on any particular Volume.
158 \item Automatic pruning of the database (removal of old records) thus
159 simplifying database administration.
160 \item Any SQL database engine can be used making Bacula very flexible.
161 Drivers currently exist for MySQL, PostgreSQL, and SQLite.
162 \item The modular but integrated design makes Bacula very scalable.
163 \item Since Bacula uses client file servers, any database or
164 other application can be properly shutdown by Bacula using the
165 native tools of the system, backed up, then restarted (all
166 within a Bacula Job).
167 \item Bacula has a built-in Job scheduler.
168 \item The Volume format is documented and there are simple C programs to
170 \item Bacula uses well defined (IANA registered) TCP/IP ports -- no rpcs, no
172 \item Bacula installation and configuration is relatively simple compared to
173 other comparable products.
174 \item According to one user Bacula is as fast as the big major commercial
176 \item According to another user Bacula is four times as fast as another
177 commercial application, probably because that application stores its catalog
178 information in a large number of individual files rather than an SQL database
180 \item Aside from several GUI administrative interfaces, Bacula has a
181 comprehensive shell administrative interface, which allows the
182 administrator to use tools such as ssh to administrate any part of
183 Bacula from anywhere (even from home).
184 \item Bacula has a Rescue CD for Linux systems with the following features:
186 \item You build it on your own system from scratch with one simple command:
187 make -- well, then make burn.
188 \item It uses your kernel
189 \item It captures your current disk parameters and builds scripts that allow
190 you to automatically repartition a disk and format it to put it back to what
192 \item It has a script that will restart your networking (with the right IP
194 \item It has a script to automatically mount your hard disks.
195 \item It has a full Bacula FD statically linked
196 \item You can easily add additional data/programs, ... to the disk.
201 \section{Current Implementation Restrictions}
202 \index[general]{Current Implementation Restrictions }
203 \index[general]{Restrictions!Current Implementation }
206 \item It is very unusual to attempt to restore two Jobs
207 that ran simultaneously in a single restore, but if
208 you do, please be aware that unless you had
209 data spooling turned on and the spool file held the full
210 contents of both Jobs during the backup, the restore will not
211 work correctly. In other terms, Bacula cannot restore
212 two jobs in the same restore if the Jobs' data blocks were
213 intermixed on the backup medium. The problem is resolved by
214 simply doing two restores, one for each Job.
215 Normally this can happen only if you manually enter specific
216 JobIds to be restored in a single restore Job.
217 \item Bacula can generally restore any backup made from one client
218 to any other client. However, if the architecture is significantly
219 different (i.e. 32 bit architecture to 64 bit or Win32 to Unix),
220 some restrictions may apply (e.g. Solaris door files do not exist
221 on other Unix/Linux machines; there are reports that Zlib compression
222 written with 64 bit machines does not always read correctly on a 32 bit
226 \section{Design Limitations or Restrictions}
227 \index[general]{Restrictions!Design Limitations or }
228 \index[general]{Design Limitations or Restrictions }
231 \item Names (resource names, Volume names, and such) defined in Bacula
232 configuration files are limited to a fixed number of
233 characters. Currently the limit is defined as 127 characters. Note,
234 this does not apply to filenames, which may be arbitrarily long.
235 \item Command line input to some of the stand alone tools -- e.g. btape,
236 bconsole is restricted to several hundred characters maximum.
237 Normally, this is not a restriction, except in the case of listing
238 multiple Volume names for programs such as {\bf bscan}. To avoid
239 this command line length restriction, please use a {\bf .bsr}
240 file to specify the Volume names.
241 \item Bacula configuration files for each of the components can be
242 any length. However, the length of an individual line is limited
243 to 500 characters after which it is truncated. If you need lines
244 longer than 500 characters for directives such as ACLs where
245 they permit a list of names are character strings simply
246 specify multiple short lines repeating the directive on
247 each line but with different list values.
251 \section{Items to Note}
252 \index[general]{Items to Note}
254 \item Bacula's Differential and Incremental \textsl{normal} backups are based
255 on time stamps. Consequently, if you move files into an existing directory
256 or move a whole directory into the backup fileset after a Full backup, those
257 files will probably not be backed up by an Incremental save because they will
258 have old dates. This problem is corrected by using Accurate mode backups
259 or by explicitly updating the date/time stamp on all moved files.
260 \item In older versions of Bacula ($<=$ 3.0.x), if you have over 4 billion file
261 entries stored in your database, the database FileId is likely to overflow.
262 This limitation does not apply to current Bacula versions.
263 \item In non \textsl{Accurate} mode, files deleted after a Full save will be
264 included in a restoration. This is typical for most similar backup programs.
265 To avoid this, use Accurate mode backup.