Warning: This document is for the development version of Bareos Documentation. The main version is bareos-18.2.

Catalog Maintenance

Catalog Database

Bareos stores its catalog in a database. Different database backends are offered:

What database will be used, can be configured in the Bareos Director configuration, see the Catalog Resource.

The database often runs on the same server as the Bareos Director. However, it is also possible to run it on a different system. This might require some more manual configuration, a PostgreSQL example can be found in Remote PostgreSQL Database.

dbconfig-common (Debian)

Since Bareos Version >= 14.2.0 the Debian (and Ubuntu) based packages support the dbconfig-common mechanism to create and update the Bareos database, according to the user choices.

The first choice is, if dbconfig-common should be used at all. If you decide against it, the database must be configured manually, see Manual Configuration.

If you decided to use dbconfig-common, the next question will only be asked, if more than one Bareos database backend (bareos-database-*) is installed. If this is the case, select the database backend you want to use.

../_images/dbconfig-1-enable.png ../_images/dbconfig-2-select-database-type.png

Depending on the selected database backend, more questions about how to access the database will be asked. Often, the default values are suitable.

The dbconfig-common configuration (and credentials) is done by the bareos-database-common package. Settings are stored in the file /etc/dbconfig-common/bareos-database-common.conf. If you need to repeat this step, you can use the dpkg-reconfigure bareos-database-common command.

The Bareos database backend will get automatically configured in /etc/bareos/bareos-dir.d/catalog/MyCatalog.conf. If the Server is not running locally you need to specify DB Address (Dir->Catalog) in the catalog ressource. A later reconfiguration might require manual adapt changes.

Warning

When using the PostgreSQL backend and updating to Bareos < 14.2.3, it is necessary to manually grant database permissions (grant_bareos_privileges), normally by

su - postgres -c /usr/lib/bareos/scripts/grant_bareos_privileges

For details see chapter Manual Configuration.

Manual Configuration

Bareos comes with a number of scripts to prepare and update the databases. All these scripts are located in the Bareos script directory, normally at /usr/lib/bareos/scripts/.

Script Stage Description
create_bareos_database installation create Bareos database
make_bareos_tables installation create Bareos tables
grant_bareos_privileges installation grant database access privileges
update_bareos_tables [-f] update update the database schema
drop_bareos_tables deinstallation remove Bareos database tables
drop_bareos_database deinstallation remove Bareos database
make_catalog_backup.pl backup backup the Bareos database, default on Linux
make_catalog_backup backup backup the Bareos database for systems without Perl
delete_catalog_backup backup helper remove the temporary Bareos database backup file

The database preparation scripts have following configuration options:

db_type
  • command line parameter $1
  • DB Driver (Dir->Catalog) from the configuration
  • installed database backends
  • fallback: postgresql
db_name
db_user
db_password

Reading the settings from the configuration require read permission for the current user. The normal PostgreSQL administrator user (postgres) doesn’t have these permissions. So if you plan to use non-default database settings, you might add the user postgres to the group bareos.

The database preparation scripts need to have password-less administrator access to the database. Depending on the distribution you’re using, this requires additional configuration. See the following section about howto achieve this for the different database systems.

To view and test the currently configured settings, use following commands:

Show current database configuration
/usr/sbin/bareos-dbcheck -B
catalog=MyCatalog
db_name=bareos
db_driver=mysql
db_user=bareos
db_password=YourPassword
db_address=
db_port=0
db_socket=
db_type=MySQL
working_dir=/var/lib/bareos
Test the database connection. Example: wrong password
/usr/sbin/bareos-dir -t -f -d 500
[...]
bareos-dir: mysql.c:204-0 Error 1045 (28000): Access denied for user 'bareos'@'localhost' (using password: YES)
bareos-dir: dird.c:1114-0 Could not open Catalog "MyCatalog", database "bareos".
bareos-dir: dird.c:1119-0 mysql.c:200 Unable to connect to MySQL server.
Database=bareos User=bareos
MySQL connect failed either server not running or your authorization is incorrect.
bareos-dir: mysql.c:239-0 closedb ref=0 connected=0 db=0
25-Apr 16:25 bareos-dir ERROR TERMINATION
Please correct the configuration in /etc/bareos/bareos-dir.d/*/*.conf

PostgreSQL

On most distributions, PostgreSQL uses ident to allow access to the database system. The database administrator account is the Unix user postgres. Normally, this user can access the database without password, as the ident mechanism is used to identify the user.

If this works on your system can be verified by

Access the local PostgreSQL database
su - postgres
psql

If your database is configured to require a password, this must be definied in the file :file:`~/.pgpass <http://www.postgresql.org/docs/8.2/static/libpq-pgpass.html>`_ in the following syntax: HOST:PORT:DATABASE:USER:PASSWORD, e.g.

PostgreSQL access credentials
localhost:*:bareos:bareos:secret

The permission of this file must be 0600 (chmod 0600 ~/.pgpass).

Again, verify that you have specified the correct settings by calling the psql command. If this connects you to the database, your credentials are good. Exit the PostgreSQL client and run the Bareos database preparation scripts:

Setup Bareos catalog database
su - postgres
/usr/lib/bareos/scripts/create_bareos_database
/usr/lib/bareos/scripts/make_bareos_tables
/usr/lib/bareos/scripts/grant_bareos_privileges

The encoding of the bareos database must be SQL_ASCII. The command create_bareos_database automatically creates the database with this encoding. This can be verified by the command psql -l, which shows information about existing databases:

List existing databases
psql -l
        List of databases
   Name    |  Owner   | Encoding
-----------+----------+-----------
 bareos    | postgres | SQL_ASCII
 postgres  | postgres | UTF8
 template0 | postgres | UTF8
 template1 | postgres | UTF8
(4 rows)

The owner of the database may vary. The Bareos database maintance scripts don’t change the default owner of the Bareos database, so it stays at the PostgreSQL administration user. The grant_bareos_privileges script grant the required permissions to the Bareos database user. In contrast, when installing (not updating) using dbconfig, the database owner will be identical with the Bareos database user.

By default, using PostgreSQL ident, a Unix user can access a database of the same name. Therefore the user bareos can access the database bareos.

Verify Bareos database on PostgreSQL as Unix user bareos (bareos-13.2.3)
root@linux:~# su - bareos -s /bin/sh
bareos@linux:~# psql
Welcome to psql 8.3.23, the PostgreSQL interactive terminal.

Type:  \copyright for distribution terms
       \h for help with SQL commands
       \? for help with psql commands
       \g or terminate with semicolon to execute query
       \q to quit

bareos=> \dt
                 List of relations
 Schema |          Name          | Type  |  Owner
--------+------------------------+-------+----------
 public | basefiles              | table | postgres
 public | cdimages               | table | postgres
 public | client                 | table | postgres
 public | counters               | table | postgres
 public | device                 | table | postgres
 public | devicestats            | table | postgres
 public | file                   | table | postgres
 public | filename               | table | postgres
 public | fileset                | table | postgres
 public | job                    | table | postgres
 public | jobhisto               | table | postgres
 public | jobmedia               | table | postgres
 public | jobstats               | table | postgres
 public | location               | table | postgres
 public | locationlog            | table | postgres
 public | log                    | table | postgres
 public | media                  | table | postgres
 public | mediatype              | table | postgres
 public | ndmpjobenvironment     | table | postgres
 public | ndmplevelmap           | table | postgres
 public | path                   | table | postgres
 public | pathhierarchy          | table | postgres
 public | pathvisibility         | table | postgres
 public | pool                   | table | postgres
 public | quota                  | table | postgres
 public | restoreobject          | table | postgres
 public | status                 | table | postgres
 public | storage                | table | postgres
 public | unsavedfiles           | table | postgres
 public | version                | table | postgres
(30 rows)

bareos=> select * from Version;
 versionid
-----------
      2002
(1 row)

bareos=> \du
                                 List of roles
   Role name   | Superuser | Create role | Create DB | Connections | Member of
---------------+-----------+-------------+-----------+-------------+-----------
 bareos        | no        | no          | no        | no limit    | {}
 postgres      | yes       | yes         | yes       | no limit    | {}
(2 rows)

bareos=> \dp
                 Access privileges for database "bareos"
 Schema |               Name                |   Type   |  Access privileges
--------+-----------------------------------+----------+--------------------------------------
 public | basefiles                         | table    | {root=arwdxt/root,bareos=arwdxt/root}
 public | basefiles_baseid_seq              | sequence | {root=rwU/root,bareos=rw/root}
...

bareos=>

Remote PostgreSQL Database

When configuring bareos with a remote database, your first step is to check the connection from the Bareos Director host into the database. A functional connection can be verified by

Access the remote PostgreSQL database
su - postgres
psql --host bareos-database.example.com

With a correct configuration you can access the database. If it fails, you need to correct the PostgreSQL servers’ configuration files.

One way to manually create the database is to execute the bareos database preparation scripts with the –host option, explained later. However, it is advised to use the dbconfig-common. Both methods require you to add the database hostname/address as DB Address (Dir->Catalog).

If you’re using dbconfig-common you should choose New Host, enter the hostname or the local address followed by the password. As dbconfig-common uses the ident authentication by default the first try to connect will fail. Don’t be bothered by that. Choose Retry when prompted. From there, read carefully and configure the database to your needs. The authentication should be set to password, as the ident method will not work with a remote server. Set the user and administrator according to your PostgreSQL servers settings.

Set the PostgreSQL server IP as DB Address (Dir->Catalog) in Catalog Resource. You can also customize other parameters or use the defaults. A quick check should display your recent changes:

Show current database configuration
/usr/sbin/bareos-dbcheck -B
catalog=MyCatalog
db_name=bareos
db_driver=postgresql
db_user=bareos
db_password=secret
db_address=bareos-database.example.com
db_port=0
db_socket=
db_type=PostgreSQL
working_dir=/var/lib/bareos

If dbconfig-common did not succeed or you choosed not to use it, run the Bareos database preparation scripts with:

Setup Bareos catalog database
su - postgres
/usr/lib/bareos/scripts/create_bareos_database --host=bareos-database.example.com
/usr/lib/bareos/scripts/make_bareos_tables --host=bareos-database.example.com
/usr/lib/bareos/scripts/grant_bareos_privileges --host=bareos-database.example.com

MySQL

MySQL user authentication is username, password and host-based. The database administrator is the user root.

On some distributions access to the MySQL database is allowed password-less as database user root, on other distributions, a password is required. On productive systems you normally want to have password secured access.

The bareos database preparation scripts require password-less access to the database. To guarantee this, create a MySQL credentials file :file:`~/.my.cnf <http://dev.mysql.com/doc/refman/4.1/en/password-security.html>`_ with the credentials of the database administrator:

MySQL credentials file .my.cnf
[client]
host=localhost
user=root
password=YourPasswordForAccessingMysqlAsRoot

Alternatively you can specifiy your database password by adding it to the file /etc/my.cnf.

Verify that you have specified the correct settings by calling the mysql command. If this connects you to the database, your credentials are good. Exit the MySQL client.

For the Bareos database connection, you should specify a database password. Otherwise the Bareos database user gets the permission to connect without password. This is not recommended. Choose a database password and add it into the Bareos Director configuration file /etc/bareos/bareos-dir.conf:

Bareos catalog configuration
...
#
# Generic catalog service
#
Catalog {
  Name = MyCatalog
  dbdriver = "mysql"
  dbname = "bareos"
  dbuser = "bareos"
  dbpassword = "YourSecretPassword"
}
...

After this, run the Bareos database preparation scripts. For Bareos <= 13.2.2, the database password must be specified as environment variable db_password. From Version >= 13.2.3 the database password is read from the configuration, if no environment variable is given.

Setup Bareos catalog database
export db_password=YourSecretPassword
/usr/lib/bareos/scripts/create_bareos_database
/usr/lib/bareos/scripts/make_bareos_tables
/usr/lib/bareos/scripts/grant_bareos_privileges

After this, you can use the mysql command to verify that your database setup is okay and works with your the Bareos database user. The result should look similar as this (here Bareos 13.2 is used on SLES11):

Verify Bareos database on MySQL
root@linux:~# mysql --user=bareos --password=YourSecretPassword bareos
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 162
Server version: 5.5.32 SUSE MySQL package

Copyright (c) 2000, 2013, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql> show tables;
+--------------------+
| Tables_in_bareos   |
+--------------------+
| BaseFiles          |
| CDImages           |
| Client             |
| Counters           |
| Device             |
| DeviceStats        |
| File               |
| FileSet            |
| Filename           |
| Job                |
| JobHisto           |
| JobMedia           |
| JobStats           |
| Location           |
| LocationLog        |
| Log                |
| Media              |
| MediaType          |
| NDMPJobEnvironment |
| NDMPLevelMap       |
| Path               |
| PathHierarchy      |
| PathVisibility     |
| Pool               |
| Quota              |
| RestoreObject      |
| Status             |
| Storage            |
| UnsavedFiles       |
| Version            |
+--------------------+
30 rows in set (0.00 sec)

mysql> describe Job;
+-----------------+---------------------+------+-----+---------+----------------+
| Field           | Type                | Null | Key | Default | Extra          |
+-----------------+---------------------+------+-----+---------+----------------+
| JobId           | int(10) unsigned    | NO   | PRI | NULL    | auto_increment |
| Job             | tinyblob            | NO   |     | NULL    |                |
| Name            | tinyblob            | NO   | MUL | NULL    |                |
| Type            | binary(1)           | NO   |     | NULL    |                |
| Level           | binary(1)           | NO   |     | NULL    |                |
| ClientId        | int(11)             | YES  |     | 0       |                |
| JobStatus       | binary(1)           | NO   |     | NULL    |                |
| SchedTime       | datetime            | YES  |     | NULL    |                |
| StartTime       | datetime            | YES  |     | NULL    |                |
| EndTime         | datetime            | YES  |     | NULL    |                |
| RealEndTime     | datetime            | YES  |     | NULL    |                |
| JobTDate        | bigint(20) unsigned | YES  |     | 0       |                |
| VolSessionId    | int(10) unsigned    | YES  |     | 0       |                |
| VolSessionTime  | int(10) unsigned    | YES  |     | 0       |                |
| JobFiles        | int(10) unsigned    | YES  |     | 0       |                |
| JobBytes        | bigint(20) unsigned | YES  |     | 0       |                |
| ReadBytes       | bigint(20) unsigned | YES  |     | 0       |                |
| JobErrors       | int(10) unsigned    | YES  |     | 0       |                |
| JobMissingFiles | int(10) unsigned    | YES  |     | 0       |                |
| PoolId          | int(10) unsigned    | YES  |     | 0       |                |
| FileSetId       | int(10) unsigned    | YES  |     | 0       |                |
| PriorJobId      | int(10) unsigned    | YES  |     | 0       |                |
| PurgedFiles     | tinyint(4)          | YES  |     | 0       |                |
| HasBase         | tinyint(4)          | YES  |     | 0       |                |
| HasCache        | tinyint(4)          | YES  |     | 0       |                |
| Reviewed        | tinyint(4)          | YES  |     | 0       |                |
| Comment         | blob                | YES  |     | NULL    |                |
+-----------------+---------------------+------+-----+---------+----------------+
27 rows in set (0,00 sec)

mysql> select * from Version;
+-----------+
| VersionId |
+-----------+
|      2002 |
+-----------+
1 row in set (0.00 sec)

mysql> exit
Bye
Modify database credentials

If you want to change the Bareos database credentials, do the following:

  • stop the Bareos director
  • modify the configuration
  • rerun the grant script grant_bareos_privileges (or modify database user directly)
  • start the Bareos director

Modify the configuration, set a new password:

bareos-dir.d/catalog/MyCatalog.conf
Catalog {
  Name = MyCatalog
  dbdriver = "mysql"
  dbname = "bareos"
  dbuser = "bareos"
  dbpassword = "MyNewSecretPassword"
}

Rerun the Bareos grant script grant_bareos_privileges

Modify database privileges
export db_password=MyNewSecretPassword
/usr/lib/bareos/scripts/grant_bareos_privileges

Sqlite

There are different versions of Sqlite available. When we use the term Sqlite, we will always refer to Sqlite3.

Sqlite is a file based database. Access via network connection is not supported. Because its setup is easy, it is a good database for testing. However, please don’t use it in a production environment.

Sqlite stores a database in a single file. Bareos creates this file at /var/lib/bareos/bareos.db.

Sqlite does not offer access permissions. The only permissions that do apply are the Unix file permissions.

The database is accessable by the following command:

Verify Bareos database on Sqlite3 (bareos-13.2.3)
sqlite3 /var/lib/bareos/bareos.db
SQLite version 3.7.6.3
Enter ".help" for instructions
Enter SQL statements terminated with a ";"
sqlite> .tables
BaseFiles           Filename            Media               Pool
CDImages            Job                 MediaType           Quota
Client              JobHisto            NDMPJobEnvironment  RestoreObject
Counters            JobMedia            NDMPLevelMap        Status
Device              JobStats            NextId              Storage
DeviceStats         Location            Path                UnsavedFiles
File                LocationLog         PathHierarchy       Version
FileSet             Log                 PathVisibility
sqlite> select * from Version;
2002
sqlite>

Retention Periods

Database Size

As mentioned above, if you do not do automatic pruning, your Catalog will grow each time you run a Job. Normally, you should decide how long you want File records to be maintained in the Catalog and set the File Retention period to that time. Then you can either wait and see how big your Catalog gets or make a calculation assuming approximately 154 bytes for each File saved and knowing the number of Files that are saved during each backup and the number of Clients you backup.

For example, suppose you do a backup of two systems, each with 100,000 files. Suppose further that you do a Full backup weekly and an Incremental every day, and that the Incremental backup typically saves 4,000 files. The size of your database after a month can roughly be calculated as:

Size = 154 * No. Systems * (100,000 * 4 + 10,000 * 26)

where we have assumed four weeks in a month and 26 incremental backups per month. This would give the following:

Size = 154 * 2 * (100,000 * 4 + 10,000 * 26) = 203,280,000 bytes

So for the above two systems, we should expect to have a database size of approximately 200 Megabytes. Of course, this will vary according to how many files are actually backed up.

You will note that the File table (containing the file attributes) make up the large bulk of the number of records as well as the space used. As a consequence, the most important Retention period will be the File Retention period.

Without proper setup and maintenance, your Catalog may continue to grow indefinitely as you run Jobs and backup Files, and/or it may become very inefficient and slow. How fast the size of your Catalog grows depends on the number of Jobs you run and how many files they backup. By deleting records within the database, you can make space available for the new records that will be added during the next Job. By constantly deleting old expired records (dates older than the Retention period), your database size will remain constant.

Setting Retention Periods

Bareos uses three Retention periods: the File Retention period, the Job Retention period, and the Volume Retention period. Of these three, the File Retention period is by far the most important in determining how large your database will become.

The File Retention and the Job Retention are specified in each Client resource as is shown below. The Volume Retention period is specified in the Pool resource, and the details are given in the next chapter of this manual.

File Retention = <time-period-specification>

The File Retention record defines the length of time that Bareos will keep File records in the Catalog database. When this time period expires, and if AutoPrune is set to yes, Bareos will prune (remove) File records that are older than the specified File Retention period. The pruning will occur at the end of a backup Job for the given Client. Note that the Client database record contains a copy of the File and Job retention periods, but Bareos uses the current values found in the Director’s Client resource to do the pruning.

Since File records in the database account for probably 80 percent of the size of the database, you should carefully determine exactly what File Retention period you need. Once the File records have been removed from the database, you will no longer be able to restore individual files in a Job. However, as long as the Job record still exists, you will be able to restore all files in the job.

Retention periods are specified in seconds, but as a convenience, there are a number of modifiers that permit easy specification in terms of minutes, hours, days, weeks, months, quarters, or years on the record. See the Configuration chapter of this manual for additional details of modifier specification.

The default File retention period is 60 days.

Job Retention = <time-period-specification>

The Job Retention record defines the length of time that Bareos will keep Job records in the Catalog database. When this time period expires, and if AutoPrune is set to yes Bareos will prune (remove) Job records that are older than the specified Job Retention period. Note, if a Job record is selected for pruning, all associated File and JobMedia records will also be pruned regardless of the File Retention period set. As a consequence, you normally will set the File retention period to be less than the Job retention period.

As mentioned above, once the File records are removed from the database, you will no longer be able to restore individual files from the Job. However, as long as the Job record remains in the database, you will be able to restore all the files backed up for the Job. As a consequence, it is generally a good idea to retain the Job records much longer than the File records.

The retention period is specified in seconds, but as a convenience, there are a number of modifiers that permit easy specification in terms of minutes, hours, days, weeks, months, quarters, or years. See the Configuration chapter of this manual for additional details of modifier specification.

The default Job Retention period is 180 days.

Auto Prune (Dir->Client)
If set to yes, Bareos will automatically apply the File retention period and the Job retention period for the Client at the end of the Job. If you turn this off by setting it to no, your Catalog will grow each time you run a Job.

Job Statistics

Bareos catalog contains lot of information about your IT infrastructure, how many files, their size, the number of video or music files etc. Using Bareos catalog during the day to get them permit to save resources on your servers.

In this chapter, you will find tips and information to measure Bareos efficiency and report statistics.

If you want to have statistics on your backups to provide some Service Level Agreement indicators, you could use a few SQL queries on the Job table to report how many:

  • jobs have run
  • jobs have been successful
  • files have been backed up

However, these statistics are accurate only if your job retention is greater than your statistics period. Ie, if jobs are purged from the catalog, you won’t be able to use them.

Now, you can use the update stats [days=num] console command to fill the JobHistory table with new Job records. If you want to be sure to take in account only good jobs, ie if one of your important job has failed but you have fixed the problem and restarted it on time, you probably want to delete the first bad job record and keep only the successful one. For that simply let your staff do the job, and update JobHistory table after two or three days depending on your organization using the [days=num] option.

These statistics records aren’t used for restoring, but mainly for capacity planning, billings, etc.

The Statistics Retention (Dir->Director) defines the length of time that Bareos will keep statistics job records in the Catalog database after the Job End time. This information is stored in the JobHistory table. When this time period expires, and if user runs prune stats command, Bareos will prune (remove) Job records that are older than the specified period.

You can use the following Job resource in your nightly BackupCatalog (Dir->Job) job to maintain statistics.

bareos-dir.d/job/BackupCatalog.conf
Job {
  Name = BackupCatalog
  ...
  RunScript {
    Console = "update stats days=3"
    Console = "prune stats yes"
    RunsWhen = After
    RunsOnClient = no
  }
}

PostgreSQL

Compacting Your PostgreSQL Database

Over time, as noted above, your database will tend to grow until Bareos starts deleting old expired records based on retention periods. After that starts, it is expected that the database size remains constant, provided that the amount of clients and files being backed up is constant.

Note that PostgreSQL uses multiversion concurrency control (MVCC), so that an UPDATE or DELETE of a row does not immediately remove the old version of the row. Space occupied by outdated or deleted row versions is only reclaimed for reuse by new rows when running VACUUM. Such outdated or deleted row versions are also referred to as dead tuples.

Since PostgreSQL Version 8.3, autovacuum is enabled by default, so that setting up a cron job to run VACUUM is not necesary in most of the cases. Note that there are two variants of VACUUM: standard VACUUM and VACUUM FULL. Standard VACUUM only marks old row versions for reuse, it does not free any allocated disk space to the operating system. Only VACUUM FULL can free up disk space, but it requires exclusive table locks so that it can not be used in parallel with production database operations and temporarily requires up to as much additional disk space that the table being processed occupies.

All database programs have some means of writing the database out in ASCII format and then reloading it. Doing so will re-create the database from scratch producing a compacted result, so below, we show you how you can do this for PostgreSQL.

For a PostgreSQL database, you could write the Bareos database as an ASCII file (bareos.sql) then reload it by doing the following:

pg_dump -c bareos > bareos.sql
cat bareos.sql | psql bareos
rm -f bareos.sql

Depending on the size of your database, this will take more or less time and a fair amount of disk space. For example, you can cd to the location of the Bareos database (typically /var/lib/pgsql/data or possible /usr/local/pgsql/data) and check the size.

Except from special cases PostgreSQL does not need to be dumped/restored to keep the database efficient. A normal process of vacuuming will prevent the database from getting too large. If you want to fine-tweak the database storage, commands such as VACUUM, VACUUM FULL, REINDEX, and CLUSTER exist specifically to keep you from having to do a dump/restore.

More details on this subject can be found in the PostgreSQL documentation. The page http://www.postgresql.org/docs/ contains links to the documentation for all PostgreSQL versions. The section Routine Vacuuming explains how VACUUM works and why it is required, see http://www.postgresql.org/docs/current/static/routine-vacuuming.html for the current PostgreSQL version.

What To Do When The Database Keeps Growing

Especially when a high number of files are beeing backed up or when working with high retention periods, it is probable that autovacuuming will not work. When starting to use Bareos with an empty Database, it is normal that the file table and other tables grow, but the growth rate should drop as soon as jobs are deleted by retention or pruning. The file table is usually the largest table in Bareos.

The reason for autovacuuming not beeing triggered is then probably the default setting of autovacuum_vacuum_scale_factor = 0.2, the current value can be shown with the following query or looked up in postgresql.conf:

SQL statement to show the autovacuum_vacuum_scale_factor parameter
bareos=# show autovacuum_vacuum_scale_factor;
 autovacuum_vacuum_scale_factor
 --------------------------------
  0.2
  (1 row)

In essence, this means that a VACUUM is only triggered when 20% of table size are obsolete. Consequently, the larger the table is, the less frequently VACUUM will be triggered by autovacuum. This make sense because vacuuming has a performance impact. While it is possible to override the autovacuum parameters on a table-by-table basis, it can then still be triggered at any time.

To learn more details about autovacuum see http://www.postgresql.org/docs/current/static/routine-vacuuming.html#AUTOVACUUM

The following example shows how to configure running VACUUM on the file table by using an admin-job in Bareos. The job will be scheduled to run at a time that should not run in parallel with normal backup jobs, here by scheduling it to run after the BackupCatalog job.

First step is to check the amount of dead tuples and if autovacuum triggers VACUUM:

Check dead tuples and vacuuming on PostgreSQL
bareos=# SELECT relname, n_dead_tup, last_vacuum, last_autovacuum, last_analyze, last_autoanalyze
FROM pg_stat_user_tables WHERE n_dead_tup > 0 ORDER BY n_dead_tup DESC;
-[ RECORD 1 ]----+------------------------------
relname          | file
n_dead_tup       | 2955116
last_vacuum      |
last_autovacuum  |
last_analyze     |
last_autoanalyze |
-[ RECORD 2 ]----+------------------------------
relname          | log
n_dead_tup       | 111298
last_vacuum      |
last_autovacuum  |
last_analyze     |
last_autoanalyze |
-[ RECORD 3 ]----+------------------------------
relname          | job
n_dead_tup       | 1785
last_vacuum      |
last_autovacuum  | 2015-01-08 01:13:20.70894+01
last_analyze     |
last_autoanalyze | 2014-12-27 18:00:58.639319+01
...

In the above example, the file table has a high number of dead tuples and it has not been vacuumed. Same for the log table, but the dead tuple count is not very high. On the job table autovacuum has been triggered.

Note that the statistics views in PostgreSQL are not persistent, their values are reset on restart of the PostgreSQL service.

To setup a scheduled admin job for vacuuming the file table, the following must be done:

  1. Create a file with the SQL statements for example /usr/local/lib/bareos/scripts/postgresql_file_table_maintenance.sql with the following content:

    SQL Script for vacuuming the file table on PostgreSQL
    \t \x
    SELECT relname, n_dead_tup, last_vacuum, last_autovacuum, last_analyze, last_autoanalyze
    FROM pg_stat_user_tables WHERE relname='file';
    VACUUM VERBOSE ANALYZE file;
    SELECT relname, n_dead_tup, last_vacuum, last_autovacuum, last_analyze, last_autoanalyze
    FROM pg_stat_user_tables WHERE relname='file';
    \t \x
    SELECT table_name,
      pg_size_pretty(pg_total_relation_size(table_name)) AS total_sz,
      pg_size_pretty(pg_total_relation_size(table_name) - pg_relation_size(table_name)) AS idx_sz
      FROM ( SELECT ('"' || relname || '"' ) AS table_name
        FROM pg_stat_user_tables WHERE relname != 'batch' ) AS all_tables
      ORDER BY pg_total_relation_size(table_name) DESC LIMIT 5;
    

    The SELECT statements are for informational purposes only, the final statement shows the total and index disk usage of the 5 largest tables.

  2. Create a shell script that runs the SQL statements, for example /usr/local/lib/bareos/scripts/postgresql_file_table_maintenance.sh with the following content:

    SQL Script for vacuuming the file table on PostgreSQL
    #!/bin/sh
    psql bareos < /usr/local/lib/bareos/scripts/postgresql_file_table_maintenance.sql
    
  3. As in PostgreSQL only the database owner or a database superuser is allowed to run VACUUM, the script will be run as the postgres user. To permit the bareos user to run the script via sudo, write the following sudo rule to a file by executing visudo -f /etc/sudoers.d/bareos_postgres_vacuum:

    sudo rule for allowing bareos to run a script as postgres
    bareos ALL = (postgres) NOPASSWD: /usr/local/lib/bareos/scripts/postgresql_file_table_maintenance.sh
    

    and make sure that /etc/sudoers includes it, usually by the line

    #includedir /etc/sudoers.d
    
  4. Create the following admin job in the director configuration

    SQL Script for vacuuming the file table on PostgreSQL
    # PostgreSQL file table maintenance job
    Job {
      Name = FileTableMaintJob
      JobDefs = DefaultJob
      Schedule = "WeeklyCycleAfterBackup"
      Type = Admin
      Priority = 20
    
      RunScript {
        RunsWhen = Before
        RunsOnClient = no
        Fail Job On Error = yes
        Command = "sudo -u postgres /usr/local/lib/bareos/scripts/postgresql_file_table_maintenance.sh"
      }
    }
    

    In this example the job will be run by the schedule WeeklyCycleAfterBackup, the Priority should be set to a higher value than Priority in the BackupCatalog job.

Repairing Your PostgreSQL Database

The same considerations apply as for Repairing Your MySQL Database. Consult the PostgreSQL documents for how to repair the database.

For Bareos specific problems, consider using bareos-dbcheck program.

MySQL/MariaDB

MySQL/MariaDB Support

As MariaDB is a fork of MySQL, we use MySQL as synonym for MariaDB and fully support it. We test our packages against the preferred MySQL fork that a distribution provides.

Compacting Your MySQL Database

Over time, as noted above, your database will tend to grow. Even though Bareos regularly prunes files, MySQL does not automatically reuse the space, and instead continues growing.

Let’s assume that you are using the InnoDB database engine (which is the default since MySQL Version 5.5).

It is recommended that you use the OPTIMIZE TABLE and ANALYZE TABLE statements regularly. This is to make sure that all indices are up to date and to recycle space inside the database files.

You can do this via the mysqlcheck command:

mysqlcheck -a -o -A

Please note that the database files are never shrunk by MySQL. If you really need to shrink the database files, you need to recreate the database. This only works if you use per-table tablespaces by setting the innodb_file_per_table configuration option. See http://dev.mysql.com/doc/refman/5.5/en/innodb-multiple-tablespaces.html for details.

Repairing Your MySQL Database

If you find that you are getting errors writing to your MySQL database, or Bareos hangs each time it tries to access the database, you should consider running MySQL’s database check and repair routines.

This can be done by running the mysqlcheck command:

mysqlcheck --all-databases

If the errors you are getting are simply SQL warnings, then you might try running bareos-dbcheck before (or possibly after) using the MySQL database repair program. It can clean up many of the orphaned record problems, and certain other inconsistencies in the Bareos database.

A typical cause of MySQL database problems is if your partition fills. In such a case, you will need to create additional space on the partition.

MySQL Table is Full

If you are running into the error The table ’File’ is full …, it is probably because on version 4.x MySQL, the table is limited by default to a maximum size of 4 GB and you have probably run into the limit. The solution can be found at: http://dev.mysql.com/doc/refman/5.0/en/full-table.html

You can display the maximum length of your table with:

mysql bareos
SHOW TABLE STATUS FROM bareos like "File";

If the column labeled “Max_data_length” is around 4Gb, this is likely to be the source of your problem, and you can modify it with:

mysql bareos
ALTER TABLE File MAX_ROWS=281474976710656;

MySQL Server Has Gone Away

If you are having problems with the MySQL server disconnecting or with messages saying that your MySQL server has gone away, then please read the MySQL documentation, which can be found at:

http://dev.mysql.com/doc/refman/5.0/en/gone-away.html

MySQL Temporary Tables

When doing backups with large numbers of files, MySQL creates some temporary tables. When these tables are small they can be held in system memory, but as they approach some size, they spool off to disk. The default location for these temp tables is /tmp. Once that space fills up, Bareos daemons such as the Storage daemon doing spooling can get strange errors. E.g.

Fatal error: spool.c:402 Spool data read error.
Fatal error: backup.c:892 Network send error to SD. ERR=Connection reset by
peer

What you need to do is setup MySQL to use a different (larger) temp directory, which can be set in the /etc/my.cnf with these variables set:

tmpdir=/path/to/larger/tmpdir
bdb_tmpdir=/path/to/larger/tmpdir

MySQL: Lock Wait Timeout

In large environments, the Bareos MySQL/MariaDB backend may run in a lock wait timeout. This can be seen as Bareos message, e.g.:

Bareos error message because of MySQL/MariaDB lock time timeout
Fatal error: sql_create.c:899 Fill File table Query failed: INSERT INTO File (FileIndex, JobId, PathId, FilenameId, LStat, MD5, DeltaSeq) SELECT batch.FileIndex, batch.JobId, Path.PathId, Filename.FilenameId,batch.LStat, batch.MD5, batch.DeltaSeq FROM batch JOIN Path ON (batch.Path = Path.Path) JOIN Filename ON (batch.Name = Filename.Name): ERR=Lock wait timeout exceeded; try restarting transaction

In this case the MySQL/MariaDB innodb_lock_wait_timeout must be increased. A value of 300 should be sufficient.

/etc/my.cnf.d/server.cnf
...
[mysqld]
innodb_lock_wait_timeout = 300
...

Backing Up Your Bareos Database

If ever the machine on which your Bareos database crashes, and you need to restore from backup tapes, one of your first priorities will probably be to recover the database. Although Bareos will happily backup your catalog database if it is specified in the FileSet, this is not a very good way to do it, because the database will be saved while Bareos is modifying it. Thus the database may be in an instable state. Worse yet, you will backup the database before all the Bareos updates have been applied.

To resolve these problems, you need to backup the database after all the backup jobs have been run. In addition, you will want to make a copy while Bareos is not modifying it. To do so, you can use two scripts provided in the release make_catalog_backup and delete_catalog_backup. These files will be automatically generated along with all the other Bareos scripts. The first script will make an ASCII copy of your Bareos database into bareos.sql in the working directory you specified in your configuration, and the second will delete the bareos.sql file.

The basic sequence of events to make this work correctly is as follows:

  • Run all your nightly backups
  • After running your nightly backups, run a Catalog backup Job
  • The Catalog backup job must be scheduled after your last nightly backup
  • You use Run Before Job (Dir->Job) to create the ASCII backup file and Run After Job (Dir->Job) to clean up

Assuming that you start all your nightly backup jobs at 1:05 am (and that they run one after another), you can do the catalog backup with the following additional Director configuration statements:

bareos-dir.d/job/BackupCatalog.conf
# Backup the catalog database (after the nightly save)
Job {
  Name = "BackupCatalog"
  Type = Backup
  Client=rufus-fd
  FileSet="Catalog"
  Schedule = "WeeklyCycleAfterBackup"
  Storage = DLTDrive
  Messages = Standard
  Pool = Default
  # This creates an ASCII copy of the catalog
  # Arguments to make_catalog_backup.pl are:
  #  make_catalog_backup.pl <catalog-name>
  RunBeforeJob = "/usr/lib/bareos/scripts/make_catalog_backup.pl MyCatalog"
  # This deletes the copy of the catalog
  RunAfterJob  = "/usr/lib/bareos/scripts/delete_catalog_backup"
  # This sends the bootstrap via mail for disaster recovery.
  # Should be sent to another system, please change recipient accordingly
  Write Bootstrap = "|/usr/sbin/bsmtp -h localhost -f \"\(Bareos\) \" -s \"Bootstrap for Job %j\" root@localhost"
}
bareos-dir.d/schedule/WeeklyCycleAfterBackup.conf
# This schedule does the catalog. It starts after the WeeklyCycle
Schedule {
  Name = "WeeklyCycleAfterBackup"
  Run = Level=Full sun-sat at 1:10
}
bareos-dir.d/fileset/Catalog.conf
# This is the backup of the catalog
FileSet {
  Name = "Catalog"
  Include {
    Options {
      signature=MD5
    }
    File = "/var/lib/bareos/bareos.sql" # database dump
    File = "/etc/bareos"                # configuration
  }
}

It is preferable to write/send the bootstrap file to another computer. It will allow you to quickly recover the database backup should that be necessary. If you do not have a bootstrap file, it is still possible to recover your database backup, but it will be more work and take longer.