diff options
| author | Alexey Shchepin <alexey@process-one.net> | 2004-10-06 19:07:21 +0400 |
|---|---|---|
| committer | Alexey Shchepin <alexey@process-one.net> | 2004-10-06 19:07:21 +0400 |
| commit | f327b06ed752197368839cfef3c111cd2b7244dc (patch) | |
| tree | 45e67055f9c8253e4fca63b9ad2211e57d1ad5a0 /doc | |
| parent | 379ba26e85e92d92ee558c783cbe5f70c4ac64d0 (diff) | |
* doc/guide.tex: Updated
SVN Revision: 274
Diffstat (limited to 'doc')
| -rw-r--r-- | doc/guide.html | 206 | ||||
| -rw-r--r-- | doc/guide.tex | 120 |
2 files changed, 239 insertions, 87 deletions
diff --git a/doc/guide.html b/doc/guide.html index 7cfa86468..70b0ad376 100644 --- a/doc/guide.html +++ b/doc/guide.html @@ -77,34 +77,35 @@ <LI><A HREF="#htoc26">4.1.3 Session Manager</A> <LI><A HREF="#htoc27">4.1.4 S2S Manager</A> </UL> +<LI><A HREF="#htoc28">4.2 How to setup ejabberd cluster</A> </UL> -<LI><A HREF="#htoc28">A Built-in Modules</A> +<LI><A HREF="#htoc29">A Built-in Modules</A> <UL><LI> -<A HREF="#htoc29">A.1 Common Options</A> +<A HREF="#htoc30">A.1 Common Options</A> <UL><LI> -<A HREF="#htoc30">A.1.1 Option <TT>iqdisc</TT></A> -<LI><A HREF="#htoc31">A.1.2 Option <TT>host</TT></A> +<A HREF="#htoc31">A.1.1 Option <TT>iqdisc</TT></A> +<LI><A HREF="#htoc32">A.1.2 Option <TT>host</TT></A> </UL> -<LI><A HREF="#htoc32">A.2 <TT>mod_announce</TT></A> -<LI><A HREF="#htoc33">A.3 <TT>mod_configure</TT></A> -<LI><A HREF="#htoc34">A.4 <TT>mod_disco</TT></A> -<LI><A HREF="#htoc35">A.5 <TT>mod_echo</TT></A> -<LI><A HREF="#htoc36">A.6 <TT>mod_irc</TT></A> -<LI><A HREF="#htoc37">A.7 <TT>mod_last</TT></A> -<LI><A HREF="#htoc38">A.8 <TT>mod_muc</TT></A> -<LI><A HREF="#htoc39">A.9 <TT>mod_offline</TT></A> -<LI><A HREF="#htoc40">A.10 <TT>mod_privacy</TT></A> -<LI><A HREF="#htoc41">A.11 <TT>mod_private</TT></A> -<LI><A HREF="#htoc42">A.12 <TT>mod_pubsub</TT></A> -<LI><A HREF="#htoc43">A.13 <TT>mod_register</TT></A> -<LI><A HREF="#htoc44">A.14 <TT>mod_roster</TT></A> -<LI><A HREF="#htoc45">A.15 <TT>mod_service_log</TT></A> -<LI><A HREF="#htoc46">A.16 <TT>mod_stats</TT></A> -<LI><A HREF="#htoc47">A.17 <TT>mod_time</TT></A> -<LI><A HREF="#htoc48">A.18 <TT>mod_vcard</TT></A> -<LI><A HREF="#htoc49">A.19 <TT>mod_version</TT></A> +<LI><A HREF="#htoc33">A.2 <TT>mod_announce</TT></A> +<LI><A HREF="#htoc34">A.3 <TT>mod_configure</TT></A> +<LI><A HREF="#htoc35">A.4 <TT>mod_disco</TT></A> +<LI><A HREF="#htoc36">A.5 <TT>mod_echo</TT></A> +<LI><A HREF="#htoc37">A.6 <TT>mod_irc</TT></A> +<LI><A HREF="#htoc38">A.7 <TT>mod_last</TT></A> +<LI><A HREF="#htoc39">A.8 <TT>mod_muc</TT></A> +<LI><A HREF="#htoc40">A.9 <TT>mod_offline</TT></A> +<LI><A HREF="#htoc41">A.10 <TT>mod_privacy</TT></A> +<LI><A HREF="#htoc42">A.11 <TT>mod_private</TT></A> +<LI><A HREF="#htoc43">A.12 <TT>mod_pubsub</TT></A> +<LI><A HREF="#htoc44">A.13 <TT>mod_register</TT></A> +<LI><A HREF="#htoc45">A.14 <TT>mod_roster</TT></A> +<LI><A HREF="#htoc46">A.15 <TT>mod_service_log</TT></A> +<LI><A HREF="#htoc47">A.16 <TT>mod_stats</TT></A> +<LI><A HREF="#htoc48">A.17 <TT>mod_time</TT></A> +<LI><A HREF="#htoc49">A.18 <TT>mod_vcard</TT></A> +<LI><A HREF="#htoc50">A.19 <TT>mod_version</TT></A> </UL> -<LI><A HREF="#htoc50">B I18n/L10n</A> +<LI><A HREF="#htoc51">B I18n/L10n</A> </UL> <!--TOC section Introduction--> @@ -723,50 +724,119 @@ router; <H4><A NAME="htoc24">4.1.1</A> Router</H4><!--SEC END --> -This module is the main router of Jabber packets on each node. It routes -them based on their destinations domains. It has two tables: local and global -routes. First, domain of packet destination searched in local table, and if it -found, then the packet is routed to appropriate process. If no, then it -searches in global table, and is routed to the appropriate <TT>ejabberd</TT> node or -process. If it does not exists in either tables, then it sent to the S2S -manager.<BR> +This module is the main router of Jabber packets on each node. It +routes them based on their destinations domains. It uses a global +routing table. A domain of packet destination is searched in the +routing table, and if it is found, then the packet is routed to +appropriate process. If no, then it is sent to the S2S manager.<BR> <BR> <!--TOC subsubsection Local Router--> <H4><A NAME="htoc25">4.1.2</A> Local Router</H4><!--SEC END --> -This module routes packets which have a destination domain equal to this server -name. If destination JID has a non-empty user part, then it routed to the -session manager, else it is processed depending on it's content.<BR> +This module routes packets which have a destination domain equal to +this server name. If destination JID has a non-empty user part, then +it is routed to the session manager, else it is processed depending on +its content.<BR> <BR> <!--TOC subsubsection Session Manager--> <H4><A NAME="htoc26">4.1.3</A> Session Manager</H4><!--SEC END --> -This module routes packets to local users. It searches for what user resource -packet must be sended via presence table. If this resource is connected to -this node, it is routed to C2S process, if it connected via another node, then -the packet is sent to session manager on that node.<BR> +This module routes packets to local users. It searches to what user +resource a packet must be sent via a presence table. Then packet is +either routed to appropriate C2S process, or stored in offline +storage, or bounced back.<BR> <BR> <!--TOC subsubsection S2S Manager--> <H4><A NAME="htoc27">4.1.4</A> S2S Manager</H4><!--SEC END --> -This module routes packets to other Jabber servers. First, it checks if an -open S2S connection from the domain of the packet source to the domain of -packet destination already exists. If it is open on another node, then it -routes the packet to S2S manager on that node, if it is open on this node, then -it is routed to the process that serves this connection, and if a connection -does not exist, then it is opened and registered.<BR> +This module routes packets to other Jabber servers. First, it +checks if an opened S2S connection from the domain of the packet +source to the domain of packet destination is existing. If it is +existing, then the S2S manager routes the packet to the process +serving this connection, else a new connection is opened.<BR> +<BR> +<!--TOC subsection How to setup ejabberd cluster--> + +<H3><A NAME="htoc28">4.2</A> How to setup ejabberd cluster</H3><!--SEC END --> + +<A NAME="sec:cluster"></A> +Suppose you already setuped ejabberd on one of machines (<TT>first</TT>), and +you need to setup another one to make <TT>ejabberd</TT> cluster. Then do +following steps: +<OL type=1><LI> +Copy <CODE>~ejabberd/.erlang.cookie</CODE> file from <TT>first</TT> to + <TT>second</TT>.<BR> +<BR> +(alt) You can also add ``<CODE>-cookie content_of_.erlang.cookie</CODE>'' + option to all ``<TT>erl</TT>'' commands below.<BR> +<BR> +<LI>On <TT>second</TT> run under `<TT>ejabberd</TT>' user in a directory + where ejabberd will work later the following command: +<PRE> +erl -sname ejabberd \ + -mnesia extra_db_nodes "['ejabberd@first']" \ + -s mnesia +</PRE>This will start mnesia serving same DB as <TT>ejabberd@first</TT>. + You can check this running ``<CODE>mnesia:info().</CODE>'' command. You + should see a lot of remote tables and a line like the following: +<PRE> +running db nodes = [ejabberd@first, ejabberd@second] +</PRE> + +<LI>Now run the following in the same ``<TT>erl</TT>'' session: +<PRE> +mnesia:change_table_copy_type(schema, node(), disc_copies). +</PRE> + This will create local disc storage for DB.<BR> +<BR> +(alt) Change storage type of `<TT>scheme</TT>' table to ``RAM and disc + copy'' on second node via web interface.<BR> +<BR> +<LI>Now you can add replicas of various tables to this node with + ``<CODE>mnesia:add_table_copy</CODE>'' or + ``<CODE>mnesia:change_table_copy_type</CODE>'' as above (just replace + ``<CODE>schema</CODE>'' with another table name and ``<CODE>disc_copies</CODE>'' + can be replaced with ``<CODE>ram_copies</CODE>'' or + ``<CODE>disc_only_copies</CODE>'').<BR> +<BR> +What tables to replicate is very depend on your needs, you can get + some hints from ``<CODE>mnesia:info().</CODE>'' command, by looking at + size of tables and default storage type for each table on 'first'.<BR> +<BR> +Replicating of table makes lookup in this table faster on this node, + but writing will be slower. And of course if machine with one of + replicas is down, other replicas will be used.<BR> +<BR> +Also section ``5.3 Table Fragmentation'' + <A HREF="http://erlang.org/doc/r9c/lib/mnesia-4.1.4/doc/html/part_frame.html">here</A> + can be useful.<BR> +<BR> +(alt) Same as in previous item, but for other tables.<BR> +<BR> +<LI>Run ``<CODE>init:stop().</CODE>'' or just ``<CODE>q().</CODE>'' to exit from + erlang shell. This probably can take some time if mnesia is not yet + transfer and process all data it needed from <TT>first</TT>.<BR> +<BR> +<LI>Now run ejabberd on <TT>second</TT> with almost the same config as + on <TT>first</TT> (you probably don't need to duplicate ``<CODE>acl</CODE>'' + and ``<CODE>access</CODE>'' options --- they will be taken from + <TT>first</TT>, and <CODE>mod_muc</CODE> and <CODE>mod_irc</CODE> should be + enabled only on one machine in cluster). +</OL> +You can repeat these steps for other machines supposed to serve this +domain.<BR> <BR> <!--TOC section Built-in Modules--> -<H2><A NAME="htoc28">A</A> Built-in Modules</H2><!--SEC END --> +<H2><A NAME="htoc29">A</A> Built-in Modules</H2><!--SEC END --> <A NAME="sec:modules"></A> <!--TOC subsection Common Options--> -<H3><A NAME="htoc29">A.1</A> Common Options</H3><!--SEC END --> +<H3><A NAME="htoc30">A.1</A> Common Options</H3><!--SEC END --> <A NAME="sec:modcommonopts"></A> The following options are used by many modules, so they are described in @@ -774,7 +844,7 @@ separate section.<BR> <BR> <!--TOC subsubsection Option <TT>iqdisc</TT>--> -<H4><A NAME="htoc30">A.1.1</A> Option <TT>iqdisc</TT></H4><!--SEC END --> +<H4><A NAME="htoc31">A.1.1</A> Option <TT>iqdisc</TT></H4><!--SEC END --> <A NAME="sec:modiqdiscoption"></A> Many modules define handlers for processing IQ queries of different namespaces @@ -807,7 +877,7 @@ Example: </PRE> <!--TOC subsubsection Option <TT>host</TT>--> -<H4><A NAME="htoc31">A.1.2</A> Option <TT>host</TT></H4><!--SEC END --> +<H4><A NAME="htoc32">A.1.2</A> Option <TT>host</TT></H4><!--SEC END --> <A NAME="sec:modhostoption"></A> This option explicitly defines hostname for the module which acts as a service.<BR> @@ -823,7 +893,7 @@ Example: </PRE> <!--TOC subsection <TT>mod_announce</TT>--> -<H3><A NAME="htoc32">A.2</A> <TT>mod_announce</TT></H3><!--SEC END --> +<H3><A NAME="htoc33">A.2</A> <TT>mod_announce</TT></H3><!--SEC END --> <A NAME="sec:modannounce"></A> This module adds support for broadcast announce messages and MOTD. @@ -866,7 +936,7 @@ Example: </PRE> <!--TOC subsection <TT>mod_configure</TT>--> -<H3><A NAME="htoc33">A.3</A> <TT>mod_configure</TT></H3><!--SEC END --> +<H3><A NAME="htoc34">A.3</A> <TT>mod_configure</TT></H3><!--SEC END --> <A NAME="sec:modconfigure"></A> Options: @@ -876,7 +946,7 @@ discipline (see <A HREF="#sec:modiqdiscoption">A.1.1</A>). </DL> <!--TOC subsection <TT>mod_disco</TT>--> -<H3><A NAME="htoc34">A.4</A> <TT>mod_disco</TT></H3><!--SEC END --> +<H3><A NAME="htoc35">A.4</A> <TT>mod_disco</TT></H3><!--SEC END --> <A NAME="sec:moddisco"></A> This module adds support for <A HREF="http://www.jabber.org/jeps/jep-0030.html">JEP-0030</A> (Service Discovery).<BR> @@ -901,7 +971,7 @@ Example: </PRE> <!--TOC subsection <TT>mod_echo</TT>--> -<H3><A NAME="htoc35">A.5</A> <TT>mod_echo</TT></H3><!--SEC END --> +<H3><A NAME="htoc36">A.5</A> <TT>mod_echo</TT></H3><!--SEC END --> <A NAME="sec:modecho"></A> This module acts as a service and simply returns to sender any Jabber packet. Module may be @@ -915,7 +985,7 @@ then prefix <TT>echo.</TT> is added to main <TT>ejabberd</TT> hostname. </DL> <!--TOC subsection <TT>mod_irc</TT>--> -<H3><A NAME="htoc36">A.6</A> <TT>mod_irc</TT></H3><!--SEC END --> +<H3><A NAME="htoc37">A.6</A> <TT>mod_irc</TT></H3><!--SEC END --> <A NAME="sec:modirc"></A> This module implements IRC transport.<BR> @@ -938,7 +1008,7 @@ Example: </PRE> <!--TOC subsection <TT>mod_last</TT>--> -<H3><A NAME="htoc37">A.7</A> <TT>mod_last</TT></H3><!--SEC END --> +<H3><A NAME="htoc38">A.7</A> <TT>mod_last</TT></H3><!--SEC END --> <A NAME="sec:modlast"></A> This module adds support for <A HREF="http://www.jabber.org/jeps/jep-0012.html">JEP-0012</A> (Last Activity)<BR> @@ -950,7 +1020,7 @@ discipline (see <A HREF="#sec:modiqdiscoption">A.1.1</A>). </DL> <!--TOC subsection <TT>mod_muc</TT>--> -<H3><A NAME="htoc38">A.8</A> <TT>mod_muc</TT></H3><!--SEC END --> +<H3><A NAME="htoc39">A.8</A> <TT>mod_muc</TT></H3><!--SEC END --> <A NAME="sec:modmuc"></A> This module implements <A HREF="http://www.jabber.org/jeps/jep-0045.html">JEP-0045</A> (Multi-User Chat) service.<BR> @@ -985,14 +1055,14 @@ Example: </PRE> <!--TOC subsection <TT>mod_offline</TT>--> -<H3><A NAME="htoc39">A.9</A> <TT>mod_offline</TT></H3><!--SEC END --> +<H3><A NAME="htoc40">A.9</A> <TT>mod_offline</TT></H3><!--SEC END --> <A NAME="sec:modoffline"></A> This module implements offline message storage.<BR> <BR> <!--TOC subsection <TT>mod_privacy</TT>--> -<H3><A NAME="htoc40">A.10</A> <TT>mod_privacy</TT></H3><!--SEC END --> +<H3><A NAME="htoc41">A.10</A> <TT>mod_privacy</TT></H3><!--SEC END --> <A NAME="sec:modprivacy"></A> This module implements Privacy Rules as defined in XMPP IM @@ -1005,7 +1075,7 @@ discipline (see <A HREF="#sec:modiqdiscoption">A.1.1</A>). </DL> <!--TOC subsection <TT>mod_private</TT>--> -<H3><A NAME="htoc41">A.11</A> <TT>mod_private</TT></H3><!--SEC END --> +<H3><A NAME="htoc42">A.11</A> <TT>mod_private</TT></H3><!--SEC END --> <A NAME="sec:modprivate"></A> This module adds support of <A HREF="http://www.jabber.org/jeps/jep-0049.html">JEP-0049</A> (Private XML Storage).<BR> @@ -1017,7 +1087,7 @@ discipline (see <A HREF="#sec:modiqdiscoption">A.1.1</A>). </DL> <!--TOC subsection <TT>mod_pubsub</TT>--> -<H3><A NAME="htoc42">A.12</A> <TT>mod_pubsub</TT></H3><!--SEC END --> +<H3><A NAME="htoc43">A.12</A> <TT>mod_pubsub</TT></H3><!--SEC END --> <A NAME="sec:modpubsub"></A> This module implements <A HREF="http://www.jabber.org/jeps/jep-0060.html">JEP-0060</A> (Publish-Subscribe Service).<BR> @@ -1042,7 +1112,7 @@ Example: </PRE> <!--TOC subsection <TT>mod_register</TT>--> -<H3><A NAME="htoc43">A.13</A> <TT>mod_register</TT></H3><!--SEC END --> +<H3><A NAME="htoc44">A.13</A> <TT>mod_register</TT></H3><!--SEC END --> <A NAME="sec:modregister"></A> This module adds support for <A HREF="http://www.jabber.org/jeps/jep-0077.html">JEP-0077</A> (In-Band Registration).<BR> @@ -1075,7 +1145,7 @@ Example: </PRE> <!--TOC subsection <TT>mod_roster</TT>--> -<H3><A NAME="htoc44">A.14</A> <TT>mod_roster</TT></H3><!--SEC END --> +<H3><A NAME="htoc45">A.14</A> <TT>mod_roster</TT></H3><!--SEC END --> <A NAME="sec:modroster"></A> This module implements roster management.<BR> @@ -1087,7 +1157,7 @@ discipline (see <A HREF="#sec:modiqdiscoption">A.1.1</A>). </DL> <!--TOC subsection <TT>mod_service_log</TT>--> -<H3><A NAME="htoc45">A.15</A> <TT>mod_service_log</TT></H3><!--SEC END --> +<H3><A NAME="htoc46">A.15</A> <TT>mod_service_log</TT></H3><!--SEC END --> <A NAME="sec:modservicelog"></A> This module adds support for logging of user packets via any jabber service. @@ -1110,7 +1180,7 @@ Example: </PRE> <!--TOC subsection <TT>mod_stats</TT>--> -<H3><A NAME="htoc46">A.16</A> <TT>mod_stats</TT></H3><!--SEC END --> +<H3><A NAME="htoc47">A.16</A> <TT>mod_stats</TT></H3><!--SEC END --> <A NAME="sec:modstats"></A> This module adds support for <A HREF="http://www.jabber.org/jeps/jep-0039.html">JEP-0039</A> (Statistics Gathering).<BR> @@ -1124,7 +1194,7 @@ TBD about access.<BR> <BR> <!--TOC subsection <TT>mod_time</TT>--> -<H3><A NAME="htoc47">A.17</A> <TT>mod_time</TT></H3><!--SEC END --> +<H3><A NAME="htoc48">A.17</A> <TT>mod_time</TT></H3><!--SEC END --> <A NAME="sec:modtime"></A> This module answers UTC time on <TT>jabber:iq:time</TT> queries.<BR> @@ -1136,7 +1206,7 @@ discipline (see <A HREF="#sec:modiqdiscoption">A.1.1</A>). </DL> <!--TOC subsection <TT>mod_vcard</TT>--> -<H3><A NAME="htoc48">A.18</A> <TT>mod_vcard</TT></H3><!--SEC END --> +<H3><A NAME="htoc49">A.18</A> <TT>mod_vcard</TT></H3><!--SEC END --> <A NAME="sec:modvcard"></A> This module implements simple Jabber User Directory (based on user vCards) @@ -1152,19 +1222,21 @@ discipline (see <A HREF="#sec:modiqdiscoption">A.1.1</A>). <DT><B><TT>search</TT></B><DD> Specifies wheather search is enabled (value is <TT>true</TT>, default) or disabled (value is <TT>false</TT>) by the service. If <TT>search</TT> is set to <TT>false</TT>, option <TT>host</TT> is ignored and service does not appear in Jabber Discovery items. +<DT><B><TT>matches</TT></B><DD> Limits the number of reported search results. If value is set to +<TT>infinity</TT> then all search results are reported. Default value is <TT>30</TT>. </DL> Example: <PRE> {modules, [ ... - {mod_vcard, [{search, false}]} + {mod_vcard, [{search, false}, {matches, 20}]} ... ]}. </PRE> <!--TOC subsection <TT>mod_version</TT>--> -<H3><A NAME="htoc49">A.19</A> <TT>mod_version</TT></H3><!--SEC END --> +<H3><A NAME="htoc50">A.19</A> <TT>mod_version</TT></H3><!--SEC END --> <A NAME="sec:modversion"></A> This module answers <TT>ejabberd</TT> version on <TT>jabber:iq:version</TT> queries.<BR> @@ -1176,7 +1248,7 @@ discipline (see <A HREF="#sec:modiqdiscoption">A.1.1</A>). </DL> <!--TOC section I18n/L10n--> -<H2><A NAME="htoc50">B</A> I18n/L10n</H2><!--SEC END --> +<H2><A NAME="htoc51">B</A> I18n/L10n</H2><!--SEC END --> <A NAME="sec:i18nl10n"></A> All built-in modules support <TT>xml:lang</TT> attribute inside IQ queries. diff --git a/doc/guide.tex b/doc/guide.tex index f656d9323..dd2775f41 100644 --- a/doc/guide.tex +++ b/doc/guide.tex @@ -721,38 +721,118 @@ Each \ejabberd{} node have following modules: \subsubsection{Router} -This module is the main router of \Jabber{} packets on each node. It routes -them based on their destinations domains. It has two tables: local and global -routes. First, domain of packet destination searched in local table, and if it -found, then the packet is routed to appropriate process. If no, then it -searches in global table, and is routed to the appropriate \ejabberd{} node or -process. If it does not exists in either tables, then it sent to the S2S -manager. +This module is the main router of \Jabber{} packets on each node. It +routes them based on their destinations domains. It uses a global +routing table. A domain of packet destination is searched in the +routing table, and if it is found, then the packet is routed to +appropriate process. If no, then it is sent to the S2S manager. \subsubsection{Local Router} -This module routes packets which have a destination domain equal to this server -name. If destination JID has a non-empty user part, then it routed to the -session manager, else it is processed depending on it's content. +This module routes packets which have a destination domain equal to +this server name. If destination JID has a non-empty user part, then +it is routed to the session manager, else it is processed depending on +its content. \subsubsection{Session Manager} -This module routes packets to local users. It searches for what user resource -packet must be sended via presence table. If this resource is connected to -this node, it is routed to C2S process, if it connected via another node, then -the packet is sent to session manager on that node. +This module routes packets to local users. It searches to what user +resource a packet must be sent via a presence table. Then packet is +either routed to appropriate C2S process, or stored in offline +storage, or bounced back. \subsubsection{S2S Manager} -This module routes packets to other \Jabber{} servers. First, it checks if an -open S2S connection from the domain of the packet source to the domain of -packet destination already exists. If it is open on another node, then it -routes the packet to S2S manager on that node, if it is open on this node, then -it is routed to the process that serves this connection, and if a connection -does not exist, then it is opened and registered. +This module routes packets to other \Jabber{} servers. First, it +checks if an opened S2S connection from the domain of the packet +source to the domain of packet destination is existing. If it is +existing, then the S2S manager routes the packet to the process +serving this connection, else a new connection is opened. + + +\subsection{How to setup ejabberd cluster} +\label{sec:cluster} + +Suppose you already setuped ejabberd on one of machines (\term{first}), and +you need to setup another one to make \ejabberd{} cluster. Then do +following steps: + +\begin{enumerate} +\item Copy \verb|~ejabberd/.erlang.cookie| file from \term{first} to + \term{second}. + + (alt) You can also add ``\verb|-cookie content_of_.erlang.cookie|'' + option to all ``\shell{erl}'' commands below. + +\item On \term{second} run under `\term{ejabberd}' user in a directory + where ejabberd will work later the following command: + +\begin{verbatim} +erl -sname ejabberd \ + -mnesia extra_db_nodes "['ejabberd@first']" \ + -s mnesia +\end{verbatim} + + This will start mnesia serving same DB as \node{ejabberd@first}. + You can check this running ``\verb|mnesia:info().|'' command. You + should see a lot of remote tables and a line like the following: + +\begin{verbatim} +running db nodes = [ejabberd@first, ejabberd@second] +\end{verbatim} + + +\item Now run the following in the same ``\shell{erl}'' session: + +\begin{verbatim} +mnesia:change_table_copy_type(schema, node(), disc_copies). +\end{verbatim} + + This will create local disc storage for DB. + + (alt) Change storage type of `\term{scheme}' table to ``RAM and disc + copy'' on second node via web interface. + + +\item Now you can add replicas of various tables to this node with + ``\verb|mnesia:add_table_copy|'' or + ``\verb|mnesia:change_table_copy_type|'' as above (just replace + ``\verb|schema|'' with another table name and ``\verb|disc_copies|'' + can be replaced with ``\verb|ram_copies|'' or + ``\verb|disc_only_copies|''). + + What tables to replicate is very depend on your needs, you can get + some hints from ``\verb|mnesia:info().|'' command, by looking at + size of tables and default storage type for each table on 'first'. + + Replicating of table makes lookup in this table faster on this node, + but writing will be slower. And of course if machine with one of + replicas is down, other replicas will be used. + + Also section ``5.3 Table Fragmentation'' + \footahref{http://erlang.org/doc/r9c/lib/mnesia-4.1.4/doc/html/part_frame.html}{here} + can be useful. + + (alt) Same as in previous item, but for other tables. + + +\item Run ``\verb|init:stop().|'' or just ``\verb|q().|'' to exit from + erlang shell. This probably can take some time if mnesia is not yet + transfer and process all data it needed from \term{first}. + + +\item Now run ejabberd on \term{second} with almost the same config as + on \term{first} (you probably don't need to duplicate ``\verb|acl|'' + and ``\verb|access|'' options --- they will be taken from + \term{first}, and \verb|mod_muc| and \verb|mod_irc| should be + enabled only on one machine in cluster). +\end{enumerate} + +You can repeat these steps for other machines supposed to serve this +domain. \appendix{} |