The Current State of Bacula

In other words, what is and what is not currently implemented and functional.

What is Implemented

• Network backup/restore with centralized Director.
• Internal scheduler for automatic Job execution.
• Scheduling of multiple Jobs at the same time.
• You may run one Job at a time or multiple simultaneous Jobs.
• Job sequencing using priorities.
• Restore of one or more files selected interactively either for the current backup or a backup prior to a specified time and date.
• Restore of a complete system starting from bare metal. This is mostly automated for Linux systems and partially automated for Solaris. See Disaster Recovery Using Bacula. This is also reported to work on Win2K/XP systems.
• Listing and Restoration of files using stand-alone bls and bextract tool programs. Among other things, this permits extraction of files when Bacula and/or the catalog are not available. Note, the recommended way to restore files is using the restore command in the Console. These programs are designed for use as a last resort.
• Ability to recreate the catalog database by scanning backup Volumes using the bscan program.
• Console interface to the Director allowing complete control. A shell, GNOME GUI and wxWidgets GUI versions of the Console program are available. Note, the GNOME GUI program currently offers very few additional features over the shell program.
• Verification of files previously cataloged, permitting a Tripwire like capability (system break-in detection).
• CRAM-MD5 password authentication between each component (daemon).
• A comprehensive and extensible configuration file for each daemon.
• Catalog database facility for remembering Volumes, Pools, Jobs, and Files backed up.
• Support for SQLite, PostgreSQL, and MySQL Catalog databases.
• User extensible queries to the SQLite, PostgreSQL and MySQL databases.
• Labeled Volumes, preventing accidental overwriting (at least by Bacula).
• Any number of Jobs and Clients can be backed up to a single Volume. That is, you can backup and restore Linux, Unix, Sun, and Windows machines to the same Volume.
• Multi-volume saves. When a Volume is full, Bacula automatically requests the next Volume and continues the backup.
• Pool and Volume library management providing Volume flexibility (e.g. monthly, weekly, daily Volume sets, Volume sets segregated by Client, ...).
• Machine independent Volume data format. Linux, Solaris, and Windows clients can all be backed up to the same Volume if desired.
• A flexible message handler including routing of messages from any daemon back to the Director and automatic email reporting.
• Multi-threaded implementation.
• Programmed to handle arbitrarily long filenames and messages.
• GZIP compression on a file by file basis done by the Client program if requested before network transit.
• Computation of MD5 or SHA1 signatures of the file data if requested.
• Saves and restores POSIX ACLs if enabled.
• Autochanger support using a simple shell interface that can interface to virtually any autoloader program. A script for mtx is provided.
• Support for autochanger barcodes - automatic tape labeling from barcodes.
• Automatic support for multiple autochanger magazines either using barcodes or by reading the tapes.
• Raw device backup/restore. Restore must be to the same device.
• All Volume blocks (approx 64K bytes) contain a data checksum.
• Access control lists for Consoles that permit restricting user access to only their data.
• Data spooling to disk during backup with subsequent write to tape from the spooled disk files. This prevents tape ``shoe shine'' during Incremental/Differential backups.
• Support for save/restore of files larger than 2GB.
• Support for 64 bit machines, e.g. amd64.
• Ability to encrypt communications between daemons using stunnel.

Advantages of Bacula Over Other Backup Programs

• Since there is a client for each machine, you can backup and restore clients of any type ensuring that all attributes of files are properly saved and restored.
• It is also possible to backup clients without any client software by using NFS or Samba. However, if possible, we recommend running a Client File daemon on each machine to be backed up.
• Bacula handles multi-volume backups.
• A full comprehensive SQL standard database of all files backed up. This permits online viewing of files saved on any particular Volume.
• Automatic pruning of the database (removal of old records) thus simplifying database administration.
• Any SQL database engine can be used making Bacula very flexible.
• The modular but integrated design makes Bacula very scalable.
• Since Bacula uses client file servers, any database or other application can be properly shutdown by Bacula using the native tools of the system, backed up, then restarted (all within a Bacula Job).
• Bacula has a built-in Job scheduler.
• The Volume format is documented and there are simple C programs to read/write it.
• Bacula uses well defined (registered) TCP/IP ports - no rpcs, no shared memory.
• Bacula installation and configuration is relatively simple compared to other comparable products.
• According to one user Bacula is as fast as the big major commercial application.
• According to another user Bacula is four times as fast as another commercial application, probably because that application stores its catalog information in a large number of individual files rather than an SQL database as Bacula does.
• Aside from a GUI administrative interface, Bacula has a comprehensive shell administrative interface, which allows the adminstrator to use tools such as ssh to administrate any part of Bacula from anywhere (even from home).

• Bacula has a Rescue CD for Linux systems with the following features:
  • You build it on your own system from scratch with one simple command: make - well, then make burn.
  • It uses your kernel
  • It captures your current disk parameters and builds scripts that allow you to automatically repartition a disk and format it to put it back to what you had before.
  • It has a script that will restart your networking (with the right IP address)
  • It has a script to automatically mount your hard disks.
  • It has a full Bacula FD statically linked
  • You can easily add additional data/programs, ... to the disk.

Current Implementation Restrictions

• It doesn't currently support ANSI and IBM tape labels.
• Typical of Microsoft, not all files can always be saved on WinNT, Win2K and WinXP when they are in use by another program. Anyone knowing the magic incantations please step forward. The files that are skipped seem to be in exclusive use by some other process, and don't appear to be too important.
• Unicode filenames (e.g. Chinese) cannot be saved or restored. This appears to be a problem only on Mac machines that are using remote mounted Windows volumes.
• If you have over 4 billion file entries stored in your database, the database FileId is likely to overflow. This is a monster database, but still possible. At some point, Bacula's FileId fields will be upgraded from 32 bits to 64 bits and this problem will go away. In the mean time, a good workaround is to use multiple databases.
• Files deleted after a Full save will be included in a restoration.
• Event handlers are not yet implemented (e.g. when Job terminates do this, ...)
• File System Modules (configurable routines for saving/restoring special files).
• Data encryption of the Volume contents.
• Bacula cannot automatically restore files for a single Job from two or more different storage devices or different media types. That is, if you use more than one storage device or media type to backup a single job, the restore process will require some manual intervention.
• There is no concept of a Pool of backup devices (i.e. if device /dev/nst0 is busy, use /dev/nst1, ...).

Design Limitations or Restrictions

• Names (resource names, Volume names, and such) defined in Bacula configuration files are limited to a fixed number of characters. Currently the limit is defined as 127 characters. Note, this does not apply to filenames, which may be arbitrarily long.