ejabberd 2.0.1 -- Installation and Operation Guide

Contents

Chapter 1  Introduction

ejabberd is a free and open source instant messaging server written in Erlang.

ejabberd is cross-platform, distributed, fault-tolerant, and based on open standards to achieve real-time communication.

ejabberd is designed to be a rock-solid and feature rich XMPP server.

ejabberd is suitable for small deployments, whether they need to be scalable or not, as well as extremely big deployments.

1.1  Key Features

ejabberd is:

  • Cross-platform: ejabberd runs under Microsoft Windows and Unix derived systems such as Linux, FreeBSD and NetBSD.
  • Distributed: You can run ejabberd on a cluster of machines and all of them will serve the same Jabber domain(s). When you need more capacity you can simply add a new cheap node to your cluster. Accordingly, you do not need to buy an expensive high-end machine to support tens of thousands concurrent users.
  • Fault-tolerant: You can deploy an ejabberd cluster so that all the information required for a properly working service will be replicated permanently on all nodes. This means that if one of the nodes crashes, the others will continue working without disruption. In addition, nodes also can be added or replaced ‘on the fly’.
  • Administrator Friendly: ejabberd is built on top of the Open Source Erlang. As a result you do not need to install an external database, an external web server, amongst others because everything is already included, and ready to run out of the box. Other administrator benefits include:
    • Comprehensive documentation.
    • Straightforward installers for Linux, Mac OS X, and Windows.
    • Web Administration.
    • Shared Roster Groups.
    • Command line administration tool.
    • Can integrate with existing authentication mechanisms.
    • Capability to send announce messages.
  • Internationalized: ejabberd leads in internationalization. Hence it is very well suited in a globalized world. Related features are:
    • Translated to 24 languages.
    • Support for IDNA.
  • Open Standards: ejabberd is the first Open Source Jabber server claiming to fully comply to the XMPP standard.

1.2  Additional Features

Moreover, ejabberd comes with a wide range of other state-of-the-art features:

  • Modular
    • Load only the modules you want.
    • Extend ejabberd with your own custom modules.
  • Security
    • SASL and STARTTLS for c2s and s2s connections.
    • STARTTLS and Dialback s2s connections.
    • Web Admin accessible via HTTPS secure access.
  • Databases
    • Internal database for fast deployment (Mnesia).
    • Native MySQL support.
    • Native PostgreSQL support.
    • ODBC data storage support.
    • Microsoft SQL Server support.
  • Authentication
    • Internal Authentication.
    • PAM, LDAP and ODBC.
    • External Authentication script.
  • Others
    • Support for virtual hosting.
    • Compressing XML streams with Stream Compression (XEP-0138).
    • Statistics via Statistics Gathering (XEP-0039).
    • IPv6 support both for c2s and s2s connections.
    • Multi-User Chat module with support for clustering and HTML logging.
    • Users Directory based on users vCards.
    • Publish-Subscribe component with support for Personal Eventing via Pubsub.
    • Support for web clients: HTTP Polling and HTTP Binding (BOSH) services.
    • IRC transport.
    • Component support: interface with networks such as AIM, ICQ and MSN installing special tranports.

Chapter 2  Installing ejabberd

2.1  Installing ejabberd with Binary Installer

Probably the easiest way to install an ejabberd instant messaging server is using the binary installer published by ProcessOne. The binary installers of released ejabberd versions are available in the ProcessOne ejabberd downloads page: http://www.process-one.net/en/ejabberd/downloads

The installer will deploy and configure a full featured ejabberd server and does not require any extra dependencies.

In *nix systems, remember to set executable the binary installer before starting it. For example: 

  chmod +x ejabberd-2.0.0_1-linux-x86-installer.bin
  ./ejabberd-2.0.0_1-linux-x86-installer.bin

ejabberd can be started manually at any time, or automatically by the operating system at system boot time.

To start and stop ejabberd manually, use the desktop shortcuts created by the installer. If the machine doesn’t have a graphical system, use the scripts ’start’ and ’stop’ in the ’bin’ directory where ejabberd is installed.

The Windows installer also adds ejabberd as a system service, and a shortcut to a debug console for experienced administrators. If you want ejabberd to be started automatically at boot time, go to the Windows service settings and set ejabberd to be automatically started. Note that the Windows service is a feature still in development, and for example it doesn’t read the file ejabberdctl.cfg.

On a *nix system, if you want ejabberd to be started as daemon at boot time, copy ejabberd.init from the ’bin’ directory to something like /etc/init.d/ejabberd (depending on your distribution) and call /etc/inid.d/ejabberd start to start it.

The ejabberdctl administration script is included in the bin directory. Please refer to the section 4.1 for details about ejabberdctl, and configurable options to fine tune the Erlang runtime system.

2.2  Installing ejabberd with Operating System specific packages

Some Operating Systems provide a specific ejabberd package adapted to the system architecture and libraries. It usually also checks dependencies and performs basic configuration tasks like creating the initial administrator account. Some examples are Debian and Gentoo. Consult the resources provided by your Operating System for more information.

Usually those packages create a script like /etc/init.d/ejabberd to start and stop ejabberd as a service at boot time.

2.3  Installing ejabberd with CEAN

CEAN (Comprehensive Erlang Archive Network) is a repository that hosts binary packages from many Erlang programs, including ejabberd and all its dependencies. The binaries are available for many different system architectures, so this is an alternative to the binary installer and Operating System’s ejabberd packages.

You will have to create your own ejabberd start script depending of how you handle your CEAN installation. The default ejabberdctl script is located into ejabberd’s priv directory and can be used as an example.

2.4  Installing ejabberd from Source Code

The canonical form for distribution of ejabberd stable releases is the source code package. Compiling ejabberd from source code is quite easy in *nix systems, as long as your system have all the dependencies.

2.4.1  Requirements

To compile ejabberd on a ‘Unix-like’ operating system, you need:

  • GNU Make
  • GCC
  • Libexpat 1.95 or higher
  • Erlang/OTP R10B-9 or newer.
  • OpenSSL 0.9.6 or higher, for STARTTLS, SASL and SSL encryption. Optional, highly recommended.
  • Zlib 1.2.3 or higher, for Stream Compression support (XEP-0138). Optional.
  • GNU Iconv 1.8 or higher, for the IRC Transport (mod_irc). Optional. Not needed on systems with GNU Libc.

2.4.2  Download Source Code

Released versions of ejabberd are available in the ProcessOne ejabberd downloads page: http://www.process-one.net/en/ejabberd/downloads

Alternatively, the latest development version can be retrieved from the Subversion repository using this command: 

  svn co http://svn.process-one.net/ejabberd/trunk ejabberd

2.4.3  Compile

To compile ejabberd execute the commands: 

  ./configure
  make

The build configuration script provides several parameters. To get the full list run the command: 

  ./configure --help

Some options that you may be interested in modifying:

--prefix=/
Specify the path prefix where the files will be copied when running the make install command.

--enable-pam
Enable the PAM authentication method.

--enable-odbc or --enable-mssql
Required if you want to use an external database. See section 3.2 for more information.

--enable-full-xml
Enable the use of XML based optimisations. It will for example use CDATA to escape characters in the XMPP stream. Use this option only if you are sure your Jabber clients include a fully compliant XML parser.

--disable-transient-supervisors
Disable the use of Erlang/OTP supervision for transient processes.

2.4.4  Install

To install ejabberd in the destination directories, run the command: 

  make install

Note that you may need to have administrative privileges in the system.

The files and directories created are, by default:

/etc/ejabberd/
Configuration files:
ejabberd.cfg
ejabberd configuration file
ejabberdctl.cfg
Configuration file of the administration script
inetrc
Network DNS configuration
/sbin/ejabberdctl
Administration script
/var/lib/ejabberd/
.erlang.cookie
Erlang cookie file
db
Mnesia database spool files
ebin
Binary Erlang files (*.beam)
priv
lib
Binary system libraries (*.so)
msgs
Translated strings (*.msgs)
/var/log/ejabberd/
Log files (see section 7.2):
ejabberd.log
ejabberd service log
sasl.log
Erlang/OTP system log

2.4.5  Start

You can use the ejabberdctl command line administration script to start and stop ejabberd.

Usage example: 

$ ejabberdctl start

$ ejabberdctl status
Node ejabberd@localhost is started. Status: started
ejabberd is running

$ ejabberdctl stop

Please refer to the section 4.1 for details about ejabberdctl, and configurable options to fine tune the Erlang runtime system.

2.4.6  Specific Notes for BSD

The command to compile ejabberd in BSD systems is: 

  gmake

2.4.7  Specific Notes for Microsoft Windows

Requirements

To compile ejabberd on a Microsoft Windows system, you need:

Compilation

We assume that we will try to put as much library as possible into C:\sdk\ to make it easier to track what is install for ejabberd.

  1. Install Erlang emulator (for example, into C:\sdk\erl5.5.5).
  2. Install Expat library into C:\sdk\Expat-2.0.0 directory.

    Copy file C:\sdk\Expat-2.0.0\Libs\libexpat.dll to your Windows system directory (for example, C:\WINNT or C:\WINNT\System32)

  3. Build and install the Iconv library into the directory C:\sdk\GnuWin32.

    Copy file C:\sdk\GnuWin32\bin\lib*.dll to your Windows system directory (more installation instructions can be found in the file README.woe32 in the iconv distribution).

    Note: instead of copying libexpat.dll and iconv.dll to the Windows directory, you can add the directories C:\sdk\Expat-2.0.0\Libs and C:\sdk\GnuWin32\bin to the PATH environment variable.

  4. Install OpenSSL in C:\sdk\OpenSSL and add C:\sdk\OpenSSL\lib\VC to your path or copy the binaries to your system directory.
  5. Install ZLib in C:\sdk\gnuWin32. Copy C:\sdk\GnuWin32\bin\zlib1.dll to your system directory. If you change your path it should already be set after libiconv install.
  6. Make sure the you can access Erlang binaries from your path. For example: set PATH=%PATH%;"C:\sdk\erl5.5.5\bin"
  7. Depending on how you end up actually installing the library you might need to check and tweak the paths in the file configure.erl.
  8. While in the directory ejabberd\src run: 
    configure.bat
nmake -f Makefile.win32
  9. Edit the file ejabberd\src\ejabberd.cfg and run 
    werl -s ejabberd -name ejabberd

2.5  Create a Jabber Account for Administration

You need a Jabber account and grant him administrative privileges to enter the ejabberd Web Admin:

  1. Register a Jabber account on your ejabberd server, for example admin1@example.org. There are two ways to register a Jabber account:
    1. Using ejabberdctl (see section 4.1): 
      % ejabberdctl register admin1 example.org FgT5bk3
    2. Using a Jabber client and In-Band Registration (see section 3.3.17).
  2. Edit the ejabberd configuration file to give administration rights to the Jabber account you created: 
      {acl, admins, {user, "admin1", "example.org"}}.
  {access, configure, [{allow, admins}]}.
    You can grant administrative privileges to many Jabber accounts, and also to accounts in other Jabber servers.
  3. Restart ejabberd to load the new configuration.
  4. Open the Web Admin (http://server:port/admin/) in your favourite browser. Make sure to enter the full JID as username (in this example: admin1@example.org. The reason that you also need to enter the suffix, is because ejabberd’s virtual hosting support.

2.6  Upgrading ejabberd

To upgrade an ejabberd installation to a new version, simply uninstall the old version, and then install the new one. Of course, it is important that the configuration file and Mnesia database spool directory are not removed.

ejabberd automatically updates the Mnesia table definitions at startup when needed. If you also use an external database for storage of some modules, check if the release notes of the new ejabberd version indicates you need to also update those tables.

Chapter 3  Configuring ejabberd

3.1  Basic Configuration

The configuration file will be loaded the first time you start ejabberd. The content from this file will be parsed and stored in the internal ejabberd database. Subsequently the configuration will be loaded from the database and any commands in the configuration file are appended to the entries in the database.

Note that ejabberd never edits the configuration file. So, the configuration changes done using the Web Admin are stored in the database, but are not reflected in the configuration file. If you want those changes to be use after ejabberd restart, you can either edit the configuration file, or remove all its content.

The configuration file contains a sequence of Erlang terms. Lines beginning with a ‘%’ sign are ignored. Each term is a tuple of which the first element is the name of an option, and any further elements are that option’s values. If the configuration file do not contain for instance the ‘hosts’ option, the old host name(s) stored in the database will be used.

You can override the old values stored in the database by adding next lines to the configuration file: 

  override_global.
  override_local.
  override_acls.

With these lines the old global options (shared between all ejabberd nodes in a cluster), local options (which are specific for this particular ejabberd node) and ACLs will be removed before new ones are added.

3.1.1  Host Names

The option hosts defines a list containing one or more domains that ejabberd will serve.

Examples:

  • Serving one domain: 
      {hosts, ["example.org"]}.
  • Serving one domain, and backwards compatible with older ejabberd versions: 
      {host, "example.org"}.
  • Serving two domains: 
      {hosts, ["example.net", "example.com"]}.

3.1.2  Virtual Hosting

Options can be defined separately for every virtual host using the host_config option. It has the following syntax: 

  {host_config, <hostname>, [<option>, <option>, ...]}.

Examples:

  • Domain example.net is using the internal authentication method while domain example.com is using the LDAP server running on the domain localhost to perform authentication: 
    {host_config, "example.net", [{auth_method, internal}]}.

{host_config, "example.com", [{auth_method, ldap},
                              {ldap_servers, ["localhost"]},
                              {ldap_uids, [{"uid"}]},
                              {ldap_rootdn, "dc=localdomain"},
                              {ldap_rootdn, "dc=example,dc=com"},
                              {ldap_password, ""}]}.
  • Domain example.net is using ODBC to perform authentication while domain example.com is using the LDAP servers running on the domains localhost and otherhost: 
    {host_config, "example.net", [{auth_method, odbc},
                              {odbc_server, "DSN=ejabberd;UID=ejabberd;PWD=ejabberd"}]}.

{host_config, "example.com", [{auth_method, ldap},
                              {ldap_servers, ["localhost", "otherhost"]},
                              {ldap_uids, [{"uid"}]},
                              {ldap_rootdn, "dc=localdomain"},
                              {ldap_rootdn, "dc=example,dc=com"},
                              {ldap_password, ""}]}.

To define specific ejabberd modules in a virtual host, you can define the global modules option with the common modules, and later add specific modules to certain virtual hosts. To accomplish that, instead of defining each option in host_config with the syntax 

  {<option-name>, <option-value>}

use this syntax: 

  {{add, <option-name>}, <option-value>}

In this example three virtual hosts have some similar modules, but there are also other different modules for some specific virtual hosts: 

% This ejabberd server has three vhosts:
{hosts, ["one.example.org", "two.example.org", "three.example.org"]}.

% Configuration of modules that are common to all vhosts
{modules,
 [
  {mod_roster,     []},
  {mod_configure,  []},
  {mod_disco,      []},
  {mod_private,    []},
  {mod_time,       []},
  {mod_last,       []},
  {mod_version,    []}
 ]}.

% Add some modules to vhost one:
{host_config, "one.example.org", [{{add, modules}, [
  {mod_echo,       [{host, "echo-service.one.example.org"}]}
  {mod_http_bind,  []},
  {mod_logxml,     []}
]}]}.

% Add a module just to vhost two:
{host_config, "two.example.org", [{{add, modules}, [
  {mod_echo,       [{host, "mirror.two.example.org"}]}
]}]}.

3.1.3  Listening Ports

The option listen defines for which addresses and ports ejabberd will listen and what services will be run on them. Each element of the list is a tuple with the following elements:

  • Port number.
  • Module that serves this port.
  • Options to this module.

The available modules, their purpose and the options allowed by each one are:

ejabberd_c2sDescriptionHandles c2s connections.
 Optionsaccess, certfile, inet6, ip, max_stanza_size, shaper, starttls, starttls_required, tls, zlib
ejabberd_s2s_inDescriptionHandles incoming s2s connections.
 Optionsinet6, ip, max_stanza_size
ejabberd_serviceDescriptionInteracts with external components (as defined in the Jabber Component Protocol (XEP-0114).
 Optionsaccess, hosts, inet6, ip, shaper, service_check_from
ejabberd_httpDescriptionHandles incoming HTTP connections.
 Optionscertfile, http_bind, http_poll, inet6, ip, request_handlers, tls, web_admin

This is a detailed description of each option allowed by the listening modules:

{access, <access rule>}
This option defines access to the port. The default value is all.
{certfile, Path}
Full path to a file containing the default SSL certificate. To define a certificate file specific for a given domain, use the global option domain_certfile.
component_check_from
This option can be used with ejabberd_service only. It is used to disable control on the from field on packets send by an external components. The option can be either true or false. The default value is true which conforms to XEP-0114.
{hosts, [Hostnames], [HostOptions]}
This option defines one or more hostnames of connected services and enables you to specify additional options including {password, Secret}.
http_bind
This option enables HTTP Binding (XEP-0124 and XEP-0206) support. HTTP Bind enables access via HTTP requests to ejabberd from behind firewalls which do not allow outgoing sockets on port 5222.

Remember that you must also install and enable the module mod_http_bind.

If HTTP Bind is enabled, it will be available at http://server:port/http-bind/. Be aware that support for HTTP Bind is also needed in the Jabber client. Remark also that HTTP Bind can be interesting to host a web-based Jabber client such as JWChat (there is a tutorial to install JWChat with instructions for ejabberd).

http_poll
This option enables HTTP Polling (XEP-0025) support. HTTP Polling enables access via HTTP requests to ejabberd from behind firewalls which do not allow outgoing sockets on port 5222.

If HTTP Polling is enabled, it will be available at http://server:port/http-poll/. Be aware that support for HTTP Polling is also needed in the Jabber client. Remark also that HTTP Polling can be interesting to host a web-based Jabber client such as JWChat (there is a tutorial to install JWChat with instructions for ejabberd).

inet6
Set up the socket for IPv6.
{ip, IPAddress}
This option specifies which network interface to listen for. For example {ip, {192, 168, 1, 1}}.
{max_stanza_size, Size}
This option specifies an approximate maximum size in bytes of XML stanzas. Approximate, because it is calculated with the precision of one block of readed data. For example {max_stanza_size, 65536}. The default value is infinity. Recommended values are 65536 for c2s connections and 131072 for s2s connections. s2s max stanza size must always much higher than c2s limit. Change this value with extreme care as it can cause unwanted disconnect if set too low.
{request_handlers, [{Path, Module}]}
To define one or several handlers that will serve HTTP requests. The Path is a list of strings; so the URIs that start with that Path will be served by Module. For example, if you want mod_foo to serve the URIs that start with /a/b/, and you also want mod_http_bind to serve the URIs /http-bind/, use this option: {request_handlers, [{["a", "b"], mod_foo}, {["http-bind"], mod_http_bind}]}
{service_check_from, true|false}
By enabling this option, ejabberd allows the component to send packets with any arbitrary domain in the ’from’ attribute. Note that XEP-0114 requires that the domain must match the hostname of the component. Only enable this option if you are completely sure you need to enable it. Default value: false.
{shaper, <access rule>}
This option defines a shaper for the port (see section 3.1.6). The default value is none.
starttls
This option specifies that STARTTLS encryption is available on connections to the port. You should also set the certfile option. You can define a certificate file for a specific domain using the global option domain_certfile.
starttls_required
This option specifies that STARTTLS encryption is required on connections to the port. No unencrypted connections will be allowed. You should also set the certfile option. You can define a certificate file for a specific domain using the global option domain_certfile.
tls
This option specifies that traffic on the port will be encrypted using SSL immediately after connecting. You should also set the certfile option.
web_admin
This option enables the Web Admin for ejabberd administration which is available at http://server:port/admin/. Login and password are the username and password of one of the registered users who are granted access by the ‘configure’ access rule.
zlib
This option specifies that Zlib stream compression (as defined in XEP-0138) is available on connections to the port. Client connections cannot use stream compression and stream encryption simultaneously. Hence, if you specify both tls (or ssl) and zlib, the latter option will not affect connections (there will be no stream compression).

There are some additional global options:

{s2s_use_starttls, true|false}
This option defines whether to use STARTTLS for s2s connections.
{s2s_certfile, Path}
Full path to a file containing a SSL certificate.
{domain_certfile, Domain, Path}
Full path to the file containing the SSL certificate for a specific domain.
{s2s_default_policy, allow|deny}
The default policy for incoming and outgoing s2s connections to other Jabber servers. The default value is allow.
{{s2s_host, Host}, allow|deny}
Defines if incoming and outgoing s2s connections with a specific remote host are allowed or denied. This allows to restrict ejabberd to only stablish s2s connections with a small list of trusted servers, or to block some specific servers.
{s2s_max_retry_delay, Seconds}
The maximum allowed delay for retry to connect after a failed connection attempt. Specified in seconds. The default value is 300 seconds (5 minutes).

For example, the following simple configuration defines:

  • There are three domains. The default certificate file is server.pem. However, the c2s and s2s connections to the domain example.com use the file example_com.pem.
  • Port 5222 listens for c2s connections with STARTTLS, and also allows plain connections for old clients.
  • Port 5223 listens for c2s connections with the old SSL.
  • Port 5269 listens for s2s connections with STARTTLS.
  • Port 5280 listens for HTTP requests, and serves the HTTP Poll service.
  • Port 5281 listens for HTTP requests, and serves the Web Admin using HTTPS as explained in section 4.2. 
{hosts, ["example.com", "example.org", "example.net"]}.
{listen,
 [
  {5222, ejabberd_c2s, [
                        {access, c2s}, 
                        {shaper, c2s_shaper},
                        starttls, {certfile, "/etc/ejabberd/server.pem"},
                        {max_stanza_size, 65536}
                       ]},
  {5223, ejabberd_c2s, [
                        {access, c2s},
                        {shaper, c2s_shaper},
                        tls, {certfile, "/etc/ejabberd/server.pem"},
                        {max_stanza_size, 65536}
                       ]},
  {5269, ejabberd_s2s_in, [
                           {shaper, s2s_shaper},
                           {max_stanza_size, 131072}
                          ]},
  {5280, ejabberd_http, [
                         http_poll
                        ]},
  {5281, ejabberd_http, [
                         web_admin,
                         tls, {certfile, "/etc/ejabberd/server.pem"},
                        ]}
 ]
}.
{s2s_use_starttls, true}.
{s2s_certfile, "/etc/ejabberd/server.pem"}.
{domain_certfile, "example.com", "/etc/ejabberd/example_com.pem"}.

In this example, the following configuration defines that:

  • c2s connections are listened for on port 5222 and 5223 (SSL) and denied for the user called ‘bad’.
  • s2s connections are listened for on port 5269 with STARTTLS for secured traffic enabled. Incoming and outgoing connections of remote Jabber servers are denied, only two servers can connect: "jabber.example.org" and "example.com".
  • Port 5280 is serving the Web Admin and the HTTP Polling service. Note that it is also possible to serve them on different ports. The second example in section 4.2 shows how exactly this can be done.
  • All users except for the administrators have a traffic of limit 1,000 Bytes/second
  • The AIM transport aim.example.org is connected to port 5233 with password ‘aimsecret’.
  • The ICQ transport JIT (icq.example.org and sms.example.org) is connected to port 5234 with password ‘jitsecret’.
  • The MSN transport msn.example.org is connected to port 5235 with password ‘msnsecret’.
  • The Yahoo! transport yahoo.example.org is connected to port 5236 with password ‘yahoosecret’.
  • The Gadu-Gadu transport gg.example.org is connected to port 5237 with password ‘ggsecret’.
  • The Jabber Mail Component jmc.example.org is connected to port 5238 with password ‘jmcsecret’.
  • The service custom has enabled the special option to avoiding checking the from attribute in the packets send by this component. The component can send packets in behalf of any users from the server, or even on behalf of any server. 
  {acl, blocked, {user, "bad"}}.
  {access, c2s, [{deny, blocked},
                 {allow, all}]}.
  {shaper, normal, {maxrate, 1000}}.
  {access, c2s_shaper, [{none, admin},
                        {normal, all}]}.
  {listen,
   [{5222, ejabberd_c2s,     [{access, c2s}, {shaper, c2s_shaper}]},
    {5223, ejabberd_c2s,     [{access, c2s},
                              ssl, {certfile, "/path/to/ssl.pem"}]},
    {5269, ejabberd_s2s_in,  []},
    {5280, ejabberd_http,    [http_poll, web_admin]},
    {5233, ejabberd_service, [{host, "aim.example.org",
                               [{password, "aimsecret"}]}]},
    {5234, ejabberd_service, [{hosts, ["icq.example.org", "sms.example.org"],
                               [{password, "jitsecret"}]}]},
    {5235, ejabberd_service, [{host, "msn.example.org",
                               [{password, "msnsecret"}]}]},
    {5236, ejabberd_service, [{host, "yahoo.example.org",
                               [{password, "yahoosecret"}]}]},
    {5237, ejabberd_service, [{host, "gg.example.org",
                               [{password, "ggsecret"}]}]},
    {5238, ejabberd_service, [{host, "jmc.example.org",
                               [{password, "jmcsecret"}]}]},
    {5239, ejabberd_service, [{host, "custom.example.org",
                               [{password, "customsecret"}]},
                              {service_check_from, false}]}
   ]
  }.
  {s2s_use_starttls, true}.
  {s2s_certfile, "/path/to/ssl.pem"}.
  {s2s_default_policy, deny}.
  {{s2s_host,"jabber.example.org"}, allow}.
  {{s2s_host,"example.com"}, allow}.

Note, that for jabberd 1.4- or WPJabber-based services you have to make the transports log and do XDB by themselves: 

  <!--
     You have to add elogger and rlogger entries here when using ejabberd.
     In this case the transport will do the logging.
  -->

  <log id='logger'>
    <host/>
    <logtype/>
    <format>%d: [%t] (%h): %s</format>
    <file>/var/log/jabber/service.log</file>
  </log>

  <!--
     Some Jabber server implementations do not provide
     XDB services (for example, jabberd2 and ejabberd).
     xdb_file.so is loaded in to handle all XDB requests.
  -->

  <xdb id="xdb">
    <host/>
    <load>
      <!-- this is a lib of wpjabber or jabberd -->
      <xdb_file>/usr/lib/jabber/xdb_file.so</xdb_file>
      </load>
    <xdb_file xmlns="jabber:config:xdb_file">
      <spool><jabberd:cmdline flag='s'>/var/spool/jabber</jabberd:cmdline></spool>
    </xdb_file>
  </xdb>

3.1.4  Authentication

The option auth_method defines the authentication method that is used for user authentication: 

  {auth_method, [<method>]}.

The following authentication methods are supported by ejabberd:

Internal

ejabberd uses its internal Mnesia database as the default authentication method.

  • auth_method: The value internal will enable the internal authentication method.

Examples:

  • To use internal authentication on example.org and LDAP authentication on example.net: 
    {host_config, "example.org", [{auth_method, [internal]}]}.
{host_config, "example.net", [{auth_method, [ldap]}]}.
  • To use internal authentication on all virtual hosts: 
    {auth_method, internal}.

SASL Anonymous and Anonymous Login

The anonymous authentication method can be configured with the following options. Remember that you can use the host_config option to set virtual host specific options (see section 3.1.2). Note that there also is a detailed tutorial regarding SASL Anonymous and anonymous login configuration.

  • auth_method: The value anonymous will enable the anonymous authentication method.
  • allow_multiple_connections: This value for this option can be either true or false and is only used when the anonymous mode is enabled. Setting it to true means that the same username can be taken multiple times in anonymous login mode if different resource are used to connect. This option is only useful in very special occasions. The default value is false.
  • anonymous_protocol: This option can take three values: sasl_anon, login_anon or both. sasl_anon means that the SASL Anonymous method will be used. login_anon means that the anonymous login method will be used. both means that SASL Anonymous and login anonymous are both enabled.

Those options are defined for each virtual host with the host_config parameter (see section 3.1.2).

Examples:

  • To enable anonymous login on all virtual hosts: 
    {auth_method, [anonymous]}.
{anonymous_protocol, login_anon}.
  • Similar as previous example, but limited to public.example.org: 
    {host_config, "public.example.org", [{auth_method, [anonymous]},
                                     {anonymous_protocol, login_anon}]}.
  • To enable anonymous login and internal authentication on a virtual host: 
    {host_config, "public.example.org", [{auth_method, [internal,anonymous]},
                                     {anonymous_protocol, login_anon}]}.
  • To enable SASL Anonymous on a virtual host: 
    {host_config, "public.example.org", [{auth_method, [anonymous]},
                                     {anonymous_protocol, sasl_anon}]}.
  • To enable SASL Anonymous and anonymous login on a virtual host: 
    {host_config, "public.example.org", [{auth_method, [anonymous]},
                                     {anonymous_protocol, both}]}.
  • To enable SASL Anonymous, anonymous login, and internal authentication on a virtual host: 
    {host_config, "public.example.org", [{auth_method, [internal,anonymous]},
                                     {anonymous_protocol, both}]}.

PAM Authentication

ejabberd supports authentication via Pluggable Authentication Modules (PAM). PAM is currently supported in AIX, FreeBSD, HP-UX, Linux, Mac OS X, NetBSD and Solaris. PAM authentication is disabled by default, so you have to configure and compile ejabberd with PAM support enabled: 

./configure --enable-pam && make install

Options:

pam_service
This option defines the PAM service name. Default is "ejabberd". Refer to the PAM documentation of your operation system for more information.

Example: 

  {auth_method, [pam]}.
  {pam_service, "ejabberd"}.

Though it is quite easy to set up PAM support in ejabberd, PAM itself introduces some security issues:

  • To perform PAM authentication ejabberd uses external C-program called epam. By default, it is located in /var/lib/ejabberd/priv/lib/ directory. You have to set it root on execution in the case when your PAM module requires root privileges (pam_unix.so for example). Also you have to grant access for ejabberd to this file and remove all other permissions from it: 
    # chown root:ejabberd /var/lib/ejabberd/priv/bin/epam
# chmod 4750 /var/lib/ejabberd/priv/bin/epam
  • Make sure you have the latest version of PAM installed on your system. Some old versions of PAM modules cause memory leaks. If you are not able to use the latest version, you can kill(1) epam process periodically to reduce its memory consumption: ejabberd will restart this process immediately.
  • epam program tries to turn off delays on authentication failures. However, some PAM modules ignore this behavior and rely on their own configuration options. The example configuration file ejabberd.pam shows how to turn off delays in pam_unix.so module. It is not a ready to use configuration file: you must use it as a hint when building your own PAM configuration instead. Note that if you want to disable delays on authentication failures in the PAM configuration file, you have to restrict access to this file, so a malicious user can’t use your configuration to perform brute-force attacks.
  • You may want to allow login access only for certain users. pam_listfile.so module provides such functionality.

3.1.5  Access Rules

ACL Definition

Access control in ejabberd is performed via Access Control Lists (ACLs). The declarations of ACLs in the configuration file have the following syntax: 

  {acl, <aclname>, {<acltype>, ...}}.

<acltype> can be one of the following:

all
Matches all JIDs. Example: 
{acl, all, all}.
{user, <username>}
Matches the user with the name <username> at the first virtual host. Example: 
{acl, admin, {user, "yozhik"}}.
{user, <username>, <server>}
Matches the user with the JID <username>@<server> and any resource. Example: 
{acl, admin, {user, "yozhik", "example.org"}}.
{server, <server>}
Matches any JID from server <server>. Example: 
{acl, exampleorg, {server, "example.org"}}.
{user_regexp, <regexp>}
Matches any local user with a name that matches <regexp> on local virtual hosts. Example: 
{acl, tests, {user_regexp, "^test[0-9]*$"}}.
{user_regexp, <regexp>, <server>}
Matches any user with a name that matches <regexp> at server <server>. Example: 
{acl, tests, {user_regexp, "^test", "example.org"}}.
{server_regexp, <regexp>}
Matches any JID from the server that matches <regexp>. Example: 
{acl, icq, {server_regexp, "^icq\\."}}.
{node_regexp, <user_regexp>, <server_regexp>}
Matches any user with a name that matches <user_regexp> at any server that matches <server_regexp>. Example: 
{acl, yohzik, {node_regexp, "^yohzik$", "^example.(com|org)$"}}.
{user_glob, <glob>}
{user_glob, <glob>, <server>}
{server_glob, <glob>}
{node_glob, <user_glob>, <server_glob>}
This is the same as above. However, it uses shell glob patterns instead of regexp. These patterns can have the following special characters:
*
matches any string including the null string.
?
matches any single character.
[...]
matches any of the enclosed characters. Character ranges are specified by a pair of characters separated by a ‘-’. If the first character after ‘[’ is a ‘!’, any character not enclosed is matched.

The following ACLs are pre-defined:

all
Matches any JID.
none
Matches no JID.

Access Rights

An entry allowing or denying access to different services looks similar to this: 

  {access, <accessname>, [{allow, <aclname>},
                          {deny, <aclname>},
                          ...
                         ]}.

When a JID is checked to have access to <accessname>, the server sequentially checks if that JID matches any of the ACLs that are named in the second elements of the tuples in the list. If it matches, the first element of the first matched tuple is returned, otherwise the value ‘deny’ is returned.

Example: 

  {access, configure, [{allow, admin}]}.
  {access, something, [{deny, badmans},
                       {allow, all}]}.

The following access rules are pre-defined:

all
Always returns the value ‘allow’.
none
Always returns the value ‘deny’.

Limiting Opened Sessions with ACL

The special access max_user_sessions specifies the maximum number of sessions (authenticated connections) per user. If a user tries to open more sessions by using different resources, the first opened session will be disconnected. The error session replaced will be sent to the disconnected session. The value for this option can be either a number, or infinity. The default value is infinity.

The syntax is: 

  {access, max_user_sessions, [{<maxnumber>, <aclname>},
                               ...
                              ]}.

Examples:

  • To limit the number of sessions per user to 10 for all users: 
      {access, max_user_sessions, [{10, all}]}.

Several connections to a remote Jabber server with ACL

The special access max_s2s_connections specifies how many simultaneus S2S connections can be stablished to a specific remote Jabber server. The default value is 1. There’s also available the access max_s2s_connections_per_node.

The syntax is: 

  {access, max_s2s_connections, [{<maxnumber>, <aclname>},
                                 ...
                                ]}.

Examples:

  • Allow up to 3 connections with each remote server: 
      {access, max_s2s_connections, [{3, all}]}.

3.1.6  Shapers

Shapers enable you to limit connection traffic. The syntax of shapers is like this: 

  {shaper, <shapername>, <kind>}.

Currently only one kind of shaper called maxrate is available. It has the following syntax: 

  {maxrate, <rate>}

where <rate> stands for the maximum allowed incoming rate in bytes per second. When a connection exceeds this limit, ejabberd stops reading from the socket until the average rate is again below the allowed maximum.

Examples:

  • To define a shaper named ‘normal’ with traffic speed limited to 1,000 bytes/second: 
      {shaper, normal, {maxrate, 1000}}.
  • To define a shaper named ‘fast’ with traffic speed limited to 50,000 bytes/second: 
      {shaper, fast, {maxrate, 50000}}.

3.1.7  Default Language

The option language defines the default language of server strings that can be seen by Jabber clients. If a Jabber client do not support xml:lang, the specified language is used. The default value is en. In order to take effect there must be a translation file <language>.msg in ejabberd’s msgs directory.

Examples:

  • To set Russian as default language: 
      {language, "ru"}.
  • To set Spanish as default language: 
      {language, "es"}.

3.2  Database and LDAP Configuration

ejabberd uses its internal Mnesia database by default. However, it is possible to use a relational database 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:

The following LDAP servers are tested with ejabberd:

  • Active Directory (see section 3.2.5)
  • OpenLDAP
  • Normally any LDAP compatible server should work; inform us about your success with a not-listed server so that we can list it here.

3.2.1  MySQL

Although this section will describe ejabberd’s configuration when you want to use the native MySQL driver, it does not describe MySQL’s installation and database creation. Check the MySQL documentation and the tutorial Using ejabberd with MySQL native driver for information regarding these topics. Note that the tutorial contains information about ejabberd’s configuration which is duplicate to this section.

Moreover, the file mysql.sql in the directory src/odbc might be interesting for you. This file contains the ejabberd schema for MySQL. At the end of the file you can find information to update your database schema.

By default ejabberd opens 10 connections to the database for each virtual host. Use this option to modify the value: 

{odbc_pool_size, 10}.

You can configure an interval to make a dummy SQL request to keep alive the connections to the database. The default value is ’undefined’, so no keepalive requests are made. Specify in seconds: for example 28800 means 8 hours. 

{odbc_keepalive_interval, undefined}.

Driver Compilation

You can skip this step if you installed ejabberd using a binary installer or if the binary packages of ejabberd you are using include support for MySQL.

  1. First, install the Erlang MySQL library. Make sure the compiled files are in your Erlang path; you can put them for example in the same directory as your ejabberd .beam files.
  2. Then, configure and install ejabberd with ODBC support enabled (this is also needed for native MySQL support!). This can be done, by using next commands: 
    ./configure --enable-odbc && make install

Authentication

The option value name may be misleading, as the auth_method name is used for access to a relational database through ODBC, as well as through the native MySQL interface. Anyway, the first configuration step is to define the odbc auth_method. For example: 

{host_config, "public.example.org", [{auth_method, [odbc]}]}.

The actual database access is defined in the option odbc_server. Its value is used to define if we want to use ODBC, or one of the two native interface available, PostgreSQL or MySQL.

To use the native MySQL interface, you can pass a tuple of the following form as parameter: 

{mysql, "Server", "Database", "Username", "Password"}

mysql is a keyword that should be kept as is. For example: 

{odbc_server, {mysql, "localhost", "test", "root", "password"}}.

Optionally, it is possible to define the MySQL port to use. This option is only useful, in very rare cases, when you are not running MySQL with the default port setting. The mysql parameter can thus take the following form: 

{mysql, "Server", Port, "Database", "Username", "Password"}

The Port value should be an integer, without quotes. For example: 

{odbc_server, {mysql, "localhost", Port, "test", "root", "password"}}.

Storage

MySQL also can be used to store information into from several ejabberd modules. See section 3.3.1 to see which modules have a version with the ‘_odbc’. This suffix indicates that the module can be used with relational databases like MySQL. To enable storage to your database, just make sure that your database is running well (see previous sections), and replace the suffix-less or ldap module variant with the odbc module variant. Keep in mind that you cannot have several variants of the same module loaded!

3.2.2  Microsoft SQL Server

Although this section will describe ejabberd’s configuration when you want to use Microsoft SQL Server, it does not describe Microsoft SQL Server’s installation and database creation. Check the MySQL documentation and the tutorial Using ejabberd with MySQL native driver for information regarding these topics. Note that the tutorial contains information about ejabberd’s configuration which is duplicate to this section.

Moreover, the file mssql.sql in the directory src/odbc might be interesting for you. This file contains the ejabberd schema for Microsoft SQL Server. At the end of the file you can find information to update your database schema.

By default ejabberd opens 10 connections to the database for each virtual host. Use this option to modify the value: 

{odbc_pool_size, 10}.

You can configure an interval to make a dummy SQL request to keep alive the connections to the database. The default value is ’undefined’, so no keepalive requests are made. Specify in seconds: for example 28800 means 8 hours. 

{odbc_keepalive_interval, undefined}.

Driver Compilation

You can skip this step if you installed ejabberd using a binary installer or if the binary packages of ejabberd you are using include support for ODBC.

If you want to use Microsoft SQL Server with ODBC, you need to configure, compile and install ejabberd with support for ODBC and Microsoft SQL Server enabled. This can be done, by using next commands: 

./configure --enable-odbc --enable-mssql && make install

Authentication

The configuration of Microsoft SQL Server is the same as the configuration of ODBC compatible servers (see section 3.2.4).

Storage

Microsoft SQL Server also can be used to store information into from several ejabberd modules. See section 3.3.1 to see which modules have a version with the ‘_odbc’. This suffix indicates that the module can be used with relational databases like Microsoft SQL Server. To enable storage to your database, just make sure that your database is running well (see previous sections), and replace the suffix-less or ldap module variant with the odbc module variant. Keep in mind that you cannot have several variants of the same module loaded!

3.2.3  PostgreSQL

Although this section will describe ejabberd’s configuration when you want to use the native PostgreSQL driver, it does not describe PostgreSQL’s installation and database creation. Check the PostgreSQL documentation and the tutorial Using ejabberd with MySQL native driver for information regarding these topics. Note that the tutorial contains information about ejabberd’s configuration which is duplicate to this section.

Also the file pg.sql in the directory src/odbc might be interesting for you. This file contains the ejabberd schema for PostgreSQL. At the end of the file you can find information to update your database schema.

By default ejabberd opens 10 connections to the database for each virtual host. Use this option to modify the value: 

{odbc_pool_size, 10}.

You can configure an interval to make a dummy SQL request to keep alive the connections to the database. The default value is ’undefined’, so no keepalive requests are made. Specify in seconds: for example 28800 means 8 hours. 

{odbc_keepalive_interval, undefined}.

Driver Compilation

You can skip this step if you installed ejabberd using a binary installer or if the binary packages of ejabberd you are using include support for PostgreSQL.

  1. First, install the Erlang pgsql library from ejabberd-modules SVN repository. Make sure the compiled files are in your Erlang path; you can put them for example in the same directory as your ejabberd .beam files.
  2. Then, configure, compile and install ejabberd with ODBC support enabled (this is also needed for native PostgreSQL support!). This can be done, by using next commands: 
    ./configure --enable-odbc && make install

Authentication

The option value name may be misleading, as the auth_method name is used for access to a relational database through ODBC, as well as through the native PostgreSQL interface. Anyway, the first configuration step is to define the odbc auth_method. For example: 

{host_config, "public.example.org", [{auth_method, [odbc]}]}.

The actual database access is defined in the option odbc_server. Its value is used to define if we want to use ODBC, or one of the two native interface available, PostgreSQL or MySQL.

To use the native PostgreSQL interface, you can pass a tuple of the following form as parameter: 

{pgsql, "Server", "Database", "Username", "Password"}

pgsql is a keyword that should be kept as is. For example: 

{odbc_server, {pgsql, "localhost", "database", "ejabberd", "password"}}.

Optionally, it is possible to define the PostgreSQL port to use. This option is only useful, in very rare cases, when you are not running PostgreSQL with the default port setting. The pgsql parameter can thus take the following form: 

{pgsql, "Server", Port, "Database", "Username", "Password"}

The Port value should be an integer, without quotes. For example: 

{odbc_server, {pgsql, "localhost", 5432, "database", "ejabberd", "password"}}.

Storage

PostgreSQL also can be used to store information into from several ejabberd modules. See section 3.3.1 to see which modules have a version with the ‘_odbc’. This suffix indicates that the module can be used with relational databases like PostgreSQL. To enable storage to your database, just make sure that your database is running well (see previous sections), and replace the suffix-less or ldap module variant with the odbc module variant. Keep in mind that you cannot have several variants of the same module loaded!

3.2.4  ODBC Compatible

Although this section will describe ejabberd’s configuration when you want to use the ODBC driver, it does not describe the installation and database creation of your database. Check the documentation of your database. The tutorial Using ejabberd with MySQL native driver also can help you. Note that the tutorial contains information about ejabberd’s configuration which is duplicate to this section.

By default ejabberd opens 10 connections to the database for each virtual host. Use this option to modify the value: 

{odbc_pool_size, 10}.

You can configure an interval to make a dummy SQL request to keep alive the connections to the database. The default value is ’undefined’, so no keepalive requests are made. Specify in seconds: for example 28800 means 8 hours. 

{odbc_keepalive_interval, undefined}.

Driver Compilation

You can skip this step if you installed ejabberd using a binary installer or if the binary packages of ejabberd you are using include support for ODBC.

  1. First, install the Erlang MySQL library. Make sure the compiled files are in your Erlang path; you can put them for example in the same directory as your ejabberd .beam files.
  2. Then, configure, compile and install ejabberd with ODBC support enabled. This can be done, by using next commands: 
    ./configure --enable-odbc && make install

Authentication

The first configuration step is to define the odbc auth_method. For example: 

{host_config, "public.example.org", [{auth_method, [odbc]}]}.

The actual database access is defined in the option odbc_server. Its value is used to defined if we want to use ODBC, or one of the two native interface available, PostgreSQL or MySQL.

To use a relational database through ODBC, you can pass the ODBC connection string as odbc_server parameter. For example: 

{odbc_server, "DSN=database;UID=ejabberd;PWD=password"}.

Storage

An ODBC compatible database also can be used to store information into from several ejabberd modules. See section 3.3.1 to see which modules have a version with the ‘_odbc’. This suffix indicates that the module can be used with ODBC compatible relational databases. To enable storage to your database, just make sure that your database is running well (see previous sections), and replace the suffix-less or ldap module variant with the odbc module variant. Keep in mind that you cannot have several variants of the same module loaded!

3.2.5  LDAP

ejabberd has built-in LDAP support. You can authenticate users against LDAP server and use LDAP directory as vCard storage. Shared rosters are not supported yet.

Connection

Parameters:

ldap_servers
List of IP addresses or DNS names of your LDAP servers. This option is required.
ldap_port
Port to connect to your LDAP server. The initial default value is 389, so it is used when nothing is set into the configuration file. If you configure a value, it is stored in ejabberd’s database. Then, if you remove that value from the configuration file, the value previously stored in the database will be used instead of the default 389.
ldap_rootdn
Bind DN. The default value is "" which means ‘anonymous connection’.
ldap_password
Bind password. The default value is "".

Example: 

  {auth_method, ldap}.
  {ldap_servers, ["ldap.example.org"]}.
  {ldap_port, 389}.
  {ldap_rootdn, "cn=Manager,dc=domain,dc=org"}.
  {ldap_password, "secret"}.

Note that current LDAP implementation does not support SSL secured communication and SASL authentication.

Authentication

You can authenticate users against an LDAP directory. Available options are:

ldap_base
LDAP base directory which stores users accounts. This option is required.
ldap_uids
LDAP attribute which holds a list of attributes to use as alternatives for getting the JID. The value is of the form: [{ldap_uidattr}] or [{ldap_uidattr, ldap_uidattr_format}]. You can use as many comma separated tuples {ldap_uidattr, ldap_uidattr_format} that is needed. The default value is [{"uid", "%u"}]. The defaut ldap_uidattr_format is "%u". The values for ldap_uidattr and ldap_uidattr_format are described as follow:
ldap_uidattr
LDAP attribute which holds the user’s part of a JID. The default value is "uid".
ldap_uidattr_format
Format of the ldap_uidattr variable. The format must contain one and only one pattern variable "%u" which will be replaced by the user’s part of a JID. For example, "%u@example.org". The default value is "%u".
ldap_filter
RFC 2254 LDAP filter. The default is none. Example: "(&(objectClass=shadowAccount)(memberOf=Jabber Users))". Please, do not forget to close brackets and do not use superfluous whitespaces. Also you must not use ldap_uidattr attribute in filter because this attribute will be substituted in LDAP filter automatically.

Examples

Common example

Let’s say ldap.example.org is the name of our LDAP server. We have users with their passwords in "ou=Users,dc=example,dc=org" directory. Also we have addressbook, which contains users emails and their additional infos in "ou=AddressBook,dc=example,dc=org" directory. Corresponding authentication section should looks like this:

  %% authentication method
  {auth_method, ldap}.
  %% DNS name of our LDAP server
  {ldap_servers, ["ldap.example.org"]}.
  %% Bind to LDAP server as "cn=Manager,dc=example,dc=org" with password "secret"
  {ldap_rootdn, "cn=Manager,dc=example,dc=org"}.
  {ldap_password, "secret"}.
  %% define the user's base
  {ldap_base, "ou=Users,dc=example,dc=org"}.
  %% We want to authorize users from 'shadowAccount' object class only
  {ldap_filter, "(objectClass=shadowAccount)"}.

Now we want to use users LDAP-info as their vCards. We have four attributes defined in our LDAP schema: "mail" — email address, "givenName" — first name, "sn" — second name, "birthDay" — birthday. Also we want users to search each other. Let’s see how we can set it up:

  {modules,
    ...
    {mod_vcard_ldap,
     [
      %% We use the same server and port, but want to bind anonymously because
      %% our LDAP server accepts anonymous requests to
      %% "ou=AddressBook,dc=example,dc=org" subtree.
      {ldap_rootdn, ""},
      {ldap_password, ""},
      %% define the addressbook's base
      {ldap_base, "ou=AddressBook,dc=example,dc=org"},
      %% uidattr: user's part of JID is located in the "mail" attribute
      %% uidattr_format: common format for our emails
      {ldap_uids, [{"mail", "%u@mail.example.org"}]},
      %% We have to define empty filter here, because entries in addressbook does not
      %% belong to shadowAccount object class
      {ldap_filter, ""},
      %% Now we want to define vCard pattern
      {ldap_vcard_map,
       [{"NICKNAME", "%u", []}, % just use user's part of JID as his nickname
        {"GIVEN", "%s", ["givenName"]},
        {"FAMILY", "%s", ["sn"]},
        {"FN", "%s, %s", ["sn", "givenName"]}, % example: "Smith, John"
        {"EMAIL", "%s", ["mail"]},
        {"BDAY", "%s", ["birthDay"]}]},
      %% Search form
      {ldap_search_fields,
       [{"User", "%u"},
        {"Name", "givenName"},
        {"Family Name", "sn"},
        {"Email", "mail"},
        {"Birthday", "birthDay"}]},
      %% vCard fields to be reported
      %% Note that JID is always returned with search results
      {ldap_search_reported,
       [{"Full Name", "FN"},
        {"Nickname", "NICKNAME"},
        {"Birthday", "BDAY"}]}
    ]},
    ...
  }.

Note that mod_vcard_ldap module checks for the existence of the user before searching in his information in LDAP.

Active Directory

Active Directory is just an LDAP-server with predefined attributes. A sample configuration is shown below:

  {auth_method, ldap}.
  {ldap_servers, ["office.org"]}.    % List of LDAP servers
  {ldap_base, "DC=office,DC=org"}. % Search base of LDAP directory
  {ldap_rootdn, "CN=Administrator,CN=Users,DC=office,DC=org"}. % LDAP manager
  {ldap_password, "*******"}. % Password to LDAP manager
  {ldap_uids, [{"sAMAccountName"}]}.
  {ldap_filter, "(memberOf=*)"}.

  {modules,
    ...
    {mod_vcard_ldap,
     [{ldap_vcard_map,
       [{"NICKNAME", "%u", []},
        {"GIVEN", "%s", ["givenName"]},
        {"MIDDLE", "%s", ["initials"]},
        {"FAMILY", "%s", ["sn"]},
        {"FN", "%s", ["displayName"]},
        {"EMAIL", "%s", ["mail"]},
        {"ORGNAME", "%s", ["company"]},
        {"ORGUNIT", "%s", ["department"]},
        {"CTRY", "%s", ["c"]},
        {"LOCALITY", "%s", ["l"]},
        {"STREET", "%s", ["streetAddress"]},
        {"REGION", "%s", ["st"]},
        {"PCODE", "%s", ["postalCode"]},
        {"TITLE", "%s", ["title"]},
        {"URL", "%s", ["wWWHomePage"]},
        {"DESC", "%s", ["description"]},
        {"TEL", "%s", ["telephoneNumber"]}]},
      {ldap_search_fields,
       [{"User", "%u"},
        {"Name", "givenName"},
        {"Family Name", "sn"},
        {"Email", "mail"},
        {"Company", "company"},
        {"Department", "department"},
        {"Role", "title"},
        {"Description", "description"},
        {"Phone", "telephoneNumber"}]},
      {ldap_search_reported,
       [{"Full Name", "FN"},
        {"Nickname", "NICKNAME"},
        {"Email", "EMAIL"}]}
    ]},
    ...
  }.

3.3  Modules Configuration

The option modules defines the list of modules that will be loaded after ejabberd’s startup. Each entry in the list is a tuple in which the first element is the name of a module and the second is a list of options for that module.

Examples:

  • In this example only the module mod_echo is loaded and no module options are specified between the square brackets: 
      {modules,
   [{mod_echo,      []}
   ]}.
  • In the second example the modules mod_echo, mod_time, and mod_version are loaded without options. Remark that, besides the last entry, all entries end with a comma: 
      {modules,
   [{mod_echo,      []},
    {mod_time,      []},
    {mod_version,   []}
   ]}.

3.3.1  Overview

The following table lists all modules included in ejabberd.

ModuleFeatureDependenciesNeeded for XMPP?
mod_adhocAd-Hoc Commands (XEP-0050) No
mod_announceManage announcementsrecommends mod_adhocNo
mod_capsRequest and cache Entity Capabilities (XEP-0115) No
mod_configureServer configuration using Ad-Hocmod_adhocNo
mod_discoService Discovery (XEP-0030) No
mod_echoEchoes Jabber packets No
mod_ircIRC transport No
mod_lastLast Activity (XEP-0012) No
mod_last_odbcLast Activity (XEP-0012)supported database (*)No
mod_mucMulti-User Chat (XEP-0045) No
mod_muc_logMulti-User Chat room loggingmod_mucNo
mod_offlineOffline message storage No
mod_offline_odbcOffline message storagesupported database (*)No
mod_privacyBlocking Communications Yes
mod_privacy_odbcBlocking Communicationssupported database (*)Yes
mod_privatePrivate XML Storage (XEP-0049) No
mod_private_odbcPrivate XML Storage (XEP-0049)supported database (*)No
mod_proxy65SOCKS5 Bytestreams (XEP-0065) No
mod_pubsubPublish-Subscribe (XEP-0060) and PEP (XEP-0163)mod_capsNo
mod_registerIn-Band Registration (XEP-0077) No
mod_rosterRoster management Yes (**)
mod_roster_odbcRoster managementsupported database (*)Yes (**)
mod_service_logCopy user messages to logger service No
mod_shared_rosterShared roster managementmod_roster orNo
  mod_roster_odbc 
mod_statsStatistics Gathering (XEP-0039) No
mod_timeEntity Time (XEP-0090) No
mod_vcardvcard-temp (XEP-0054) No
mod_vcard_ldapvcard-temp (XEP-0054)LDAP serverNo
mod_vcard_odbcvcard-temp (XEP-0054)supported database (*)No
mod_versionSoftware Version (XEP-0092) No
  • (*) For a list of supported databases, see section 3.2.
  • (**) This module or a similar one with another database backend is needed for XMPP compliancy.

You can see which database backend each module needs by looking at the suffix:

  • No suffix, this means that the modules uses Erlang’s built-in database Mnesia as backend.
  • ‘_odbc’, this means that the module needs a supported database (see 3.2) as backend.
  • ‘_ldap’, this means that the module needs an LDAP server as backend.

If you want to, it is possible to use a relational database to store pieces of information. You can do this by changing the module name to a name with an _odbc suffix in ejabberd config file. You can use a relational database for the following data:

  • Last connection date and time: Use mod_last_odbc instead of mod_last.
  • Offline messages: Use mod_offline_odbc instead of mod_offline.
  • Rosters: Use mod_roster_odbc instead of mod_roster.
  • Users’ VCARD: Use mod_vcard_odbc instead of mod_vcard.
  • Private XML storage: Use mod_private_odbc instead of mod_private.
  • User rules for blocking communications: Use mod_privacy_odbc instead of mod_privacy.

You can find more contributed modules on the ejabberd website. Please remember that these contributions might not work or that they can contain severe bugs and security leaks. Therefore, use them at your own risk!

3.3.2  Common Options

The following options are used by many modules. Therefore, they are described in this separate section.

iqdisc

Many modules define handlers for processing IQ queries of different namespaces to this server or to a user (e. g. to example.org or to user@example.org). This option defines processing discipline for these queries. Possible values are:

no_queue
All queries of a namespace with this processing discipline are processed immediately. This also means that no other packets can be processed until this one has been completely processed. Hence this discipline is not recommended if the processing of a query can take a relatively long time.
one_queue
In this case a separate queue is created for the processing of IQ queries of a namespace with this discipline. In addition, the processing of this queue is done in parallel with that of other packets. This discipline is most recommended.
{queues, N}
: N separate queues are created to process the queries. The queries are thus process in parallel, but in a controlled way.
parallel
For every packet with this discipline a separate Erlang process is spawned. Consequently, all these packets are processed in parallel. Although spawning of Erlang process has a relatively low cost, this can break the server’s normal work, because the Erlang emulator has a limit on the number of processes (32000 by default).

Example: 

  {modules,
   [
    ...
    {mod_time, [{iqdisc, no_queue}]},
    ...
   ]}.

host

This option defines the Jabber ID of a service provided by an ejabberd module. The keyword "@HOST@" is replaced at start time with the real virtual host string.

This example configures the echo module to provide its echoing service in the Jabber ID mirror.example.org: 

  {modules,
   [
    ...
    {mod_echo, [{host, "mirror.example.org"}]},
    ...
   ]}.

However, if there are several virtual hosts and this module is enabled in all of them, the "@HOST@" keyword must be used: 

  {modules,
   [
    ...
    {mod_echo, [{host, "mirror.@HOST@"}]},
    ...
   ]}.

3.3.3  mod_announce

This module enables configured users to broadcast announcements and to set the message of the day (MOTD). Configured users can perform these actions with a Jabber client either using Ad-hoc commands or sending messages to specific JIDs.

The Ad-hoc commands are listed in the Server Discovery. For this feature to work, mod_adhoc must be enabled.

The specific JIDs where messages can be sent are listed bellow. The first JID in each entry will apply only to the specified virtual host example.org, while the JID between brackets will apply to all virtual hosts in ejabberd.

example.org/announce/all (example.org/announce/all-hosts/all)
The message is sent to all registered users. If the user is online and connected to several resources, only the resource with the highest priority will receive the message. If the registered user is not connected, the message will be stored offline in assumption that offline storage (see section 3.3.12) is enabled.
example.org/announce/online (example.org/announce/all-hosts/online)
The message is sent to all connected users. If the user is online and connected to several resources, all resources will receive the message.
example.org/announce/motd (example.org/announce/all-hosts/motd)
The message is set as the message of the day (MOTD) and is sent to users when they login. In addition the message is sent to all connected users (similar to announce/online).
example.org/announce/motd/update (example.org/announce/all-hosts/motd/update)
The message is set as message of the day (MOTD) and is sent to users when they login. The message is not sent to any currently connected user.
example.org/announce/motd/delete (example.org/announce/all-hosts/motd/delete)
Any message sent to this JID removes the existing message of the day (MOTD).

Options:

access
This option specifies who is allowed to send announcements and to set the message of the day (by default, nobody is able to send such messages).

Examples:

  • Only administrators can send announcements: 
      {access, announce, [{allow, admins}]}.

  {modules,
   [
    ...
    {mod_adhoc, []},
    {mod_announce, [{access, announce}]},
    ...
   ]}.
  • Administrators as well as the direction can send announcements: 
      {acl, direction, {user, "big_boss", "example.org"}}.
  {acl, direction, {user, "assistant", "example.org"}}.
  {acl, admins, {user, "admin", "example.org"}}.
  ...
  {access, announce, [{allow, admins},
                      {allow, direction}]}.
  ...
  {modules,
   [
    ...
    {mod_adhoc, []},
    {mod_announce, [{access, announce}]},
    ...
   ]}.

Note that mod_announce can be resource intensive on large deployments as it can broadcast lot of messages. This module should be disabled for instances of ejabberd with hundreds of thousands users.

3.3.4  mod_disco

This module adds support for Service Discovery (XEP-0030). With this module enabled, services on your server can be discovered by Jabber clients. Note that ejabberd has no modules with support for the superseded Jabber Browsing (XEP-0011) and Agent Information (XEP-0094). Accordingly, Jabber clients need to have support for the newer Service Discovery protocol if you want them be able to discover the services you offer.

Options:

iqdisc
This specifies the processing discipline for Service Discovery (http://jabber.org/protocol/disco#items and http://jabber.org/protocol/disco#info) IQ queries (see section 3.3.2).
extra_domains
With this option, extra domains can be added to the Service Discovery item list.

Examples:

  • To serve a link to the Jabber User Directory on jabber.org: 
      {modules,
   [
    ...
    {mod_disco, [{extra_domains, ["users.jabber.org"]}]},
    ...
   ]}.
  • To serve a link to the transports on another server: 
      {modules,
   [
    ...
    {mod_disco, [{extra_domains, ["icq.example.com",
                                  "msn.example.com"]}]},
    ...
   ]}.
  • To serve a link to a few friendly servers: 
      {modules,
   [
    ...
    {mod_disco, [{extra_domains, ["example.org",
                                  "example.com"]}]},
    ...
   ]}.

3.3.5  mod_echo

This module simply echoes any Jabber packet back to the sender. This mirror can be of interest for ejabberd and Jabber client debugging.

Options:

host
This option defines the Jabber ID of the service. If the host option is not specified, the Jabber ID will be the hostname of the virtual host with the prefix ‘echo.’. The keyword "@HOST@" is replaced at start time with the real virtual host name.

Example: Mirror, mirror, on the wall, who is the most beautiful of them all? 

  {modules,
   [
    ...
    {mod_echo, [{host, "mirror.example.org"}]},
    ...
   ]}.

3.3.6  mod_http_bind

This module implements XMPP over Bosh (formerly known as HTTP Binding) as outlined by XEP-0206. It extends ejabberd’s built in HTTP service with a configurable resource at which this service will be hosted.

To use HTTP-Binding, enable the module: 

{modules,
 [
  ...
  {mod_http_bind, []},
  ...
]}.

and add http_bind in the HTTP service. For example: 

{listen, 
 [
  ...
  {5280, ejabberd_http, [
                         http_bind,
                         http_poll,
                         web_admin
                        ]
  },
  ...
]}.

With this configuration, the module will serve the requests sent to http://example.org:5280/http-bind/ Remember that this page is not designed to be used by web browsers, it is used by Jabber clients that support XMPP over Bosh.

If you want to set the service in a different URI path or use a different module, you can configure it manually using the option request_handlers. For example: 

{listen, 
 [
  ...
  {5280, ejabberd_http, [
                         {request_handlers, [{["http-bind"], mod_http_bind}]},
                         http_poll,
                         web_admin
                        ]
  },
  ...
]}.

3.3.7  mod_http_fileserver

This simple module serves files from the local disk over HTTP.

Options:

docroot
Directory to serve the files.
accesslog
File to log accesses using an Apache-like format. No log will be recorded if this option is not specified.

This example configuration will serve the files from the local directory /var/www in the address http://example.org:5280/pub/archive/. To use this module you must enable it: 

{modules,
 [
  ...
  {mod_http_fileserver, [
                         {docroot, "/var/www"}, 
                         {accesslog, "/var/log/ejabberd/access.log"}
                        ]
  },
  ...
]}.

And define it as a handler in the HTTP service: 

{listen, 
 [
  ...
  {5280, ejabberd_http, [
                         ...
                         {request_handlers, [
                                             ...
                                             {["pub", "archive"], mod_http_fileserver},
                                             ...
                                            ]
                         },
                         ...
                        ]
  },
  ...
]}.

3.3.8  mod_irc

This module is an IRC transport that can be used to join channels on IRC servers.

End user information:

  • A Jabber client with ‘groupchat 1.0’ support or Multi-User Chat support (XEP-0045) is necessary to join IRC channels.
  • An IRC channel can be joined in nearly the same way as joining a Jabber Multi-User Chat room. The difference is that the room name will be ‘channel%irc.example.org’ in case irc.example.org is the IRC server hosting ‘channel’. And of course the host should point to the IRC transport instead of the Multi-User Chat service.
  • You can register your nickame by sending ‘IDENTIFY password’ to
    nickserver!irc.example.org@irc.jabberserver.org.
  • Entering your password is possible by sending ‘LOGIN nick password’
    to nickserver!irc.example.org@irc.jabberserver.org.
  • When using a popular Jabber server, it can occur that no connection can be achieved with some IRC servers because they limit the number of conections from one IP.

Options:

host
This option defines the Jabber ID of the service. If the host option is not specified, the Jabber ID will be the hostname of the virtual host with the prefix ‘irc.’. The keyword "@HOST@" is replaced at start time with the real virtual host name.
access
This option can be used to specify who may use the IRC transport (default value: all).
default_encoding
Set the default IRC encoding (default value: "koi8-r").

Examples:

  • In the first example, the IRC transport is available on (all) your virtual host(s) with the prefix ‘irc.’. Furthermore, anyone is able to use the transport. The default encoding is set to "iso8859-15". 
      {modules,
   [
    ...
    {mod_irc, [{access, all}, {default_encoding, "iso8859-15"}]},
    ...
   ]}.
  • In next example the IRC transport is available with JIDs with prefix irc-t.net. Moreover, the transport is only accessible by paying customers registered on our domains and on other servers. 
      {acl, paying_customers, {user, "customer1", "example.net"}}.
  {acl, paying_customers, {user, "customer2", "example.com"}}.
  {acl, paying_customers, {user, "customer3", "example.org"}}.
  ...
  {access, paying_customers, [{allow, paying_customers},
                              {deny, all}]}.
  ...
  {modules,
   [
    ...
    {mod_irc, [{access, paying_customers},
               {host, "irc.example.net"}]},
    ...
   ]}.