docs.ejabberd.im

Database Configuration


Supported storages

ejabberd uses its internal Mnesia database by default. However, it is possible to use a relational database, key-value storage or an LDAP server to store persistent, long-living data. ejabberd is very flexible: you can configure different authentication methods for different virtual hosts, you can configure different authentication mechanisms for the same virtual host (fallback), you can set different storage systems for modules, and so forth.

The following databases are supported by ejabberd:

Please check LDAP Configuration section for documentation about using LDAP.

Database Schema

When using external database backend, ejabberd does not create schema and tables by itself. If you plan to use MySQL, PostgreSQL, MS SQL or SQLite, you must create the schema before you run ejabberd.

  • If installing ejabberd from sources, you will find sql script for your backend in the installation directory. By default: /usr/local/lib/ejabberd/priv/sql

  • If installing ejabberd from Process-One installer, the init scripts are located in the ejabberd's installation path under <base>/lib/ejabberd*/priv/sql

If using MySQL or PostgreSQL, you can choose between the default or the new schemas.

See ejabberd SQL Database Schema for details on database schemas.

Virtual Hosting

Important note about virtual hosting: if you define several domains in ejabberd.yml (see section Host Names), you probably want that each virtual host uses a different configuration of database, authentication and storage, so that usernames do not conflict and mix between different virtual hosts. For that purpose, the options described in the next sections must be set inside a host_config for each vhost (see section Virtual Hosting). For example:

host_config:
  public.example.org:
    sql_type: pgsql
    sql_server: localhost
    sql_database: database-public-example-org
    sql_username: ejabberd
    sql_password: password
    auth_method: [sql]

Default database

You can simplify the configuration by setting the default database. This can be done with the default_db top-level option:

default_db: mnesia|sql: This will define the default database for a module lacking db_type option or if auth_method option is not set.

Relational Databases

Default and New Schemas

There are two database schemas available in ejabberd: the default schema is preferable when serving one massive domain, the new schema is preferable when serving many small domains.

The default schema stores only one XMPP domain in the database. The XMPP domain is not stored as this is the same for all the accounts, and this saves space in massive deployments. However, to handle several domains, you have to setup one database per domain and configure each one independently using host_config, so in that case you may prefer the new schema.

The new schema stores the XMPP domain in a new column server_host in the database entries, so it allows to handle several XMPP domains in a single ejabberd database. Using this schema is preferable when serving several XMPP domains and changing domains from time to time. However, if you have only one massive domain, you may prefer to use the default schema.

To use the new schema, edit the ejabberd configuration file and enable new_sql_schema top-level option:

new_sql_schema: true

Now, when creating the new database, remember to use the proper SQL schema! For example, if you are using MySQL and choose the default schema, use mysql.sql. If you are using PostgreSQL and need the new schema, use pg.new.sql.

If you already have a MySQL or PostgreSQL database with the default schema and contents, you can upgrade it to the new schema:

  • MySQL: Edit the file sql/mysql.old-to.new.sql which is included with ejabberd, fill DEFAULT_HOST in the first line, and import that SQL file in your database. Then enable the new_sql_schema option in the ejabberd configuration, and restart ejabberd.

  • PostgreSQL: First enable new_sql_schema and mod_admin_update_sql in your ejabberd configuration:

        new_sql_schema: true
        modules:
          mod_admin_update_sql: {}
    

    then restart ejabberd, and finally execute the update_sql command:

        ejabberdctl update_sql
    

SQL Options

The actual database access is defined in the options with sql_ prefix. The values are used to define if we want to use ODBC, or one of the two native interface available, PostgreSQL or MySQL.

To configure SQL there are several top-level options:

Example of plain ODBC connection:

sql_server: "DSN=database;UID=ejabberd;PWD=password"

Example of MySQL connection:

sql_type: mysql
sql_server: server.company.com
sql_port: 3306 # the default
sql_database: mydb
sql_username: user1
sql_password: "**********"
sql_pool_size: 5

SQL Authentication

You can authenticate users against an SQL database, see the option auth_method in the Authentication section.

To store the passwords in SCRAM format instead of plaintext, see the SCRAM section.

SQL Storage

Several ejabberd modules have options called db_type, and can store their tables in an SQL database instead of internal.

In this sense, if you defined your database access using the SQL Options, you can configure a module to use your database by adding the option db_type: sql to that module.

Alternatively, if you want all modules to use your SQL database when possible, you may prefer to set SQL as your default database.

Redis

Redis is an advanced key-value cache and store. You can use it to store transient data, such as records for C2S (client) sessions. There are several options available:

redis_server: String: A hostname of the Redis server. The default is localhost.

redis_port: Port: The port where the Redis server is accepting connections. The default is 6379.

redis_password: String: The password to the Redis server. The default is an empty string, i.e. no password.

redis_db: N: Redis database number. The default is 0.

redis_connect_timeout: N: A number of seconds to wait for the connection to be established to the Redis server. The default is 1 second.

Example configuration:

redis_server: redis.server.com
redis_db: 1

Microsoft SQL Server

For now, MS SQL is only supported in Unix-like OS'es. You need to have unixODBC installed on your machine. Also, in some cases you need to add machine name to sql_username, especially when you have sql_server defined as an IP address, e.g.:

sql_type: mssql
sql_server: 1.2.3.4
...
sql_username: user1@host

By default, ejabberd will use the FreeTDS driver. You need to have the driver file libtdsodbc.so installed in your library PATH on your system.

If the FreeTDS driver is not installed in a standard location, or if you want to use another ODBC driver, you can specify the path to the driver using the sql_odbc_driver option, available in ejabberd 20.12 or later. For example, if you want to use Microsoft ODBC Driver 17 for SQL Server:

sql_odbc_driver: "/opt/microsoft/msodbcsql17/lib64/libmsodbcsql-17.3.so.1.1"

Note that if you use a Microsoft driver, you may have to use an IP address instead of a host name for the sql_server option.