<?xml version="1.0"?>
<document>
<properties>
<title>Components</title>
<author email="cmanolache@yahoo.com">Costin Manolache</author>
<author email="jfrederic.clere@fujitsu-siemens.com">Jean-Frederic Clere</author>
<date>$Date: 2003/05/16 10:28:44 $</date>
</properties>
    <section name="Intro"><p>Each component instance has a name, that is used for configuration and at runtime. Each component has a number of configurable properties. The following rules are used:
<ul><li>The name is composed from the type and a local part, separated with a ':' ( example: channel.unixsocket:/tmp/jk.socket ) </li>
<li>The 'type' consist of '.' and ascii characters.  It is mapped to a JMX 'domain'.  </li>
<li>The local part consists of ascii characters and .:/; 
<p>Note that '=,' are not currently allowed - a future version may support the jmx syntax by using quotes to separate the local part from the property and value ( in .properties mode we must use '=' to separate the value from type, local name and property name ). </p></li>
<li>The property is a simple name, with no dots. </li>
<li>A simple form of substitution is used in values, where $(property) will be replaced with a previously defined setting. If the property has ':' in it, it'll take the value from the object, if not it'll take the value from a global map.</li></ul></p>
</section>
        <section name="Common properties">
            <p>Common properties for all components</p>
            <p>
                <table>
                    <tr>
                        <th>Property name</th>
                        <th>Default</th>
                        <th>Description</th>
                    </tr>
                    <tr>
                        <td>disabled</td>
                        <td>0 (false)</td>
                        <td>"disabled" state for the component, 1=true 0=false</td>
                    </tr>
                    <tr>
                        <td>debug</td>
                        <td>0 (false)</td>
                        <td>Debug level for the component, 0=disabled, 1..10 enabled. Higher levels
                            generate more debug.</td>
                    </tr>
                    <tr>
                        <td>version</td>
                        <td>0</td>
                        <td>'Generation' of the component config. Important for runtime reconfiguration.
                            If you edit the config file or set the shmem properties, you need to also
                            upgrade the version of the modified component. The config layer will detect
                            the change and call the setter method.</td>
                     </tr>
                </table>
            </p>
        </section>
        <section name="workerEnv">
            <p>This component represent the core jk2, it has the default logger for all other components. Is the central controller, it controls global properties
and  provides access to all other objects</p>
            <p>
                <table>
                    <tr>
                        <th>Property name</th>
                        <th>Default</th>
                        <th>Description</th>
                    </tr>
                    <tr>
                        <td>logger</td>
                        <td>logger</td>
                        <td>Default loger used by jk2 components, can be changed in the config file, normally it defaults to "logger" the Alias for the default logger for the Server/platform.</td>
                    </tr>
                    <tr>
                        <td>sslEnable</td>
                        <td>1 (true)</td>
                        <td>Enable handling of SSL</td>
                    </tr>
                    <tr>
                        <td>timing</td>
                        <td>0</td>
                        <td>Will jk2 get request timing (needs APR?)</td>
                    </tr>
                    <tr>
                        <td>forwardKeySize</td>
                        <td>not set</td>
                        <td>Enable filling of javax.servlet.request.key_size</td>
                    </tr>
                    <tr>
                        <td>forwardURICompat</td>
                        <td>set</td>
                        <td>Pass the URI untouched.</td>
                    </tr>
                    <tr>
                        <td>forwardURICompatUnparsed</td>
                        <td>not set</td>
                        <td>Parse the URI until the '?'.</td>
                    </tr>
                    <tr>
                        <td>forwardURIEscaped</td>
                        <td>not set</td>
                        <td>Pass the URI escaped.</td>
                    </tr>
                </table>
            </p>
            <p>Only one of the forwardURI option could be used it replaces the default value.</p>
        </section>
        <section name="config">
            <p>The config component, hold the detail of the conifg system, such config file name, create global defines</p>
            <p>
                <table>
                    <tr>
                       <th>Property name</th>
                       <th>Default</th>
                       <th>Description</th>
                    </tr>
                    <tr>
                        <td>file</td>
                        <td>${serverRoot}/conf/workers2.properties</td>
                        <td>Location of the workers2.properties file</td>
                    </tr>
                    <tr>
                        <td>debug</td>
                        <td>0</td>
                        <td>Set the debug level of the config component</td>
                    </tr>
                    <tr>
                        <td>debugEnv</td>
                        <td>0</td>
                        <td>Set the debug level of the hidden env component </td>
                    </tr>
                </table>
            </p>
        </section>
        <section name="uriMap"/>
        <section name="shm">
            <p>Shared memory descriptor</p>
            <p>
                <table>
                    <tr>
                        <th>Property name</th>
                        <th>Default</th>
                        <th>Description</th>
                    </tr>
                    <tr>
                        <td>file</td>
                        <td>No default value</td>
                        <td>Name of the file that will be mmapped to use as shared memory.</td>
                    </tr>
                    <tr>
                        <td>size</td>
                        <td>No default value</td>
                        <td>Size of the file.</td>
                    </tr>
                </table>
            </p>
        </section>
        <section name="uri">
            <p>A uri stores a pattern that is used
 to match requests to workers, and asociated properties</p>
            <p>If the uri name doesn't have a slash then it is considered as a virtual host
            directive. Uri name can have a virtual host name and(or) port associated with. Format
            of such a name is <b>hostname</b> or <b>hostname:port</b> where hostname
            is virtual server name and the port is vitual server port number. The port number
            is used only for the non default server ports.</p>
            <p>
            Special case is a default server named as <b>[uri:*]</b> that is used when the virtual
            host cannot be found inside the configuration. All the uri directives not containing
            host name belongs to this default server making global mappings.
            </p>
            <p>
            Addition wild char scheme id <b>[uri:*:port]</b> that is used when you wish to
            match any virtual host having specified (non-default) port number, like [uri:*:443].
            This will map all the virtual hosts no mather what is their name but that have port number 443.            
            </p>
            <p>
            The order how the host names are resolved is :
            <ul>
                <li>Exact host name and optional non default port number</li>
                <li>Alias matching host name and port number</li>
                <li>*:port if the port is other then default</li>
                <li>Default server</li>
            </ul>
            </p>
            <p>
                <table>                
                    <tr>
                        <th>Property name</th>
                        <th>Default</th>
                        <th>Description</th>
                    </tr>
                    <tr>
                        <td>group</td>
                        <td>lb:0 (The default loadbalancer)</td>
                        <td>Name of the tomcat group or worker that will process the request corresponding to the uri. This used
                            to be called 'worker'</td>
                    </tr>
                    <tr>
                        <td>context</td>
                        <td/>
                        <td>the context path for this uri component (webapp style).</td>
                    </tr>
                    <tr>
                        <td>servlet</td>
                        <td/>
                        <td>Servlet path for this mapping</td>
                    </tr>
                    <tr>
                        <td>alias</td>
                        <td/>
                        <td>server name alias. This setting should only be used for 
                            host uris like [uri:myHost:myPort] ( i.e. no /) </td>
                    </tr>
                </table>
            </p>
        </section>
        <section name="vm">
            <p>Represents the JVM when used as inprocess container
            </p>
            <p>
                <table>
                    <tr>
                        <th>Property name</th>
                        <th>Default</th>
                        <th>Description</th>
                    </tr>
                    <tr>
                        <td>JVM</td>
                        <td>(Autoguess)</td>
                        <td>JVM to use for this vm</td>
                    </tr>
                    <tr>
                        <td>OPT</td>
                        <td/>
                        <td>Option to pass to this vm, this is a multivalued property</td>
                    </tr>
                    <tr>
                        <td>classpath</td>
                        <td/>
                        <td>-Djava.class.path 0ption to pass to this vm, this is a multivalued property</td>
                    </tr>
                </table>
            </p>
        </section>
        <section name="channels">
            <p>A channel represents a transport protocol, connecting 2
sides  for RPC communication. The most common and standard is the tcp socket.
Other  important  channels are unix socket and jni</p>
            <subsection name="channel.un">
                <p>
    AF_UNIX socket. Only on UNIX like platform. These sockets are faster
    than "normal" sockets but they are limited to the machine. 
</p>
                <p>
                    <table>
                        <tr>
                            <th>Property name</th>
                            <th>Default</th>
                            <th>Description</th>
                        </tr>
                        <tr>
                            <td>file</td>
                            <td>Name of socket</td>
                            <td>Name of the socket file (It is created by the Tomcat ChannelUn)</td>
                        </tr>
                    </table>
                </p>
            </subsection>
            <subsection name="channel.socket">
                <p>
    Defines a communication transport to a remote Servlet Engine. </p>

<p>The name of the channels should be: channel.socket:HOST:PORT, where HOST and PORT are the 
tomcat Ajp location.  You could use other names and explicitely set HOST and PORT, but this
is discouraged. In most cases, you don't need to set any other config - just add a line like
[channel.socket:localhost:8009] and all other things will have good defaults. 
</p>
<p>
Tomcat Engine must be set with jvmRoute="HOST:PORT", to match the default tomcatId of the channel.
</p>
                <p>
                    <table>
                        <tr>
                            <th>Property name</th>
                            <th>Default</th>
                            <th>Description</th>
                        </tr>
                        <tr>
                            <td>port</td>
                            <td>extracted from the component name</td>
                            <td>Port where Tomcat is listening. It is automatically extracted from the name - you shouldn't have to specify it explicitely.</td>
                        </tr>
                        <tr>
                            <td>host</td>
                            <td>extracted from the component name</td>
                            <td>Remote host. You should use the name, no need to override it</td>
                        </tr>
                        <tr>
                            <td>graceful</td>
                            <td>0</td>
                            <td>If 1, only requests for existing sessions will be forwarded</td>
                        </tr>
                        <tr>
                            <td>keepalive</td>
                            <td>0</td>
                            <td>? </td>
                        </tr>
                        <tr>
                            <td>lbfactor</td>
                            <td>1</td>
                            <td>
    Load balancing factor to use. At this moment, it'll be set on the worker,
    but in future it should be possible to use lb on a channel level.
  </td>
                        </tr>
                        <tr>
                            <td>group</td>
                            <td>lb</td>
                            <td>loadbalanced groups to which this channel and the associated worker will be added, multivalued. You need to set it only if you have an advanced setup with multiple clusters.</td>
                        </tr>
                        <tr>
                            <td>tomcatId</td>
                            <td>Automatically set to the localname ( host:port )</td>
                            <td>Must match the JVM route on tomcat Engine, for load balancing</td>
                        </tr>
                    </table>
                </p>
            </subsection>
            <subsection name="channel.apr">
                <p>
    A communication transport to a remote Engine using APR library
    <b>Magic:</b> The local part of the name will be the Engine name,
    to use when defining the uri mappings. For example
    channel.apr.local_9009 will automatically define an engine named
    local_9009, and if no other setting is set ajp13 will be used for
    communication.
    <b>Magic:</b> If no channel is defined in the config, a default channel
    will be constructed with port=8009, engine=DEFAULT, worker=ajp13 -
    named 'channel.apr.DEFAULT'
</p>
                <p>
                    <table>
                        <tr>
                            <th>Property name</th>
                            <th>Default</th>
                            <th>Description</th>
                        </tr>
                        <tr>
                            <td>port</td>
                            <td>8009</td>
                            <td>Port where Tomcat is listening</td>
                        </tr>
                        <tr>
                            <td>host</td>
                            <td>localhost</td>
                            <td>Remote host</td>
                        </tr>
                        <tr>
                            <td>keepalive</td>
                            <td>0 (disabled)</td>
                            <td>If set to 1 then it enables the use of keep-alive packets on TCP connection </td>
                        </tr>
                        <tr>
                            <td>timeout</td>
                            <td>0 (infinite)</td>
                            <td>Socket timeout for sending and receiving</td>
                        </tr>
                        <tr>
                            <td>ndelay</td>
                            <td>0</td>
                            <td>If set to 1 Disables the Nagle algorithm for send coalescing</td>
                        </tr>
                        <tr>
                            <td>lbfactor</td>
                            <td>1</td>
                            <td>
    Load balancing factor to use. At this moment, it'll be set on the worker,
    but in future it should be possible to use lb on a channel level.
  </td>
                        </tr>
                        <tr>
                            <td>group</td>
                            <td>lb:0</td>
                            <td>loadbalanced groups to which this channel and the associated worker will be added, multivalued</td>
                        </tr>
                    </table>
                </p>
            </subsection>
            <subsection name="channel.jni">
                <p>The jni channel, used if tomcat is started inprocess</p>
            </subsection>
        </section>
        <section name="workers">
            <p>
             For the moment 4 worker types are supported: worker.jni,ajp13,status,lb.
            </p>
            <subsection name="worker.jni">
                <p>worker used in inprocess, holds the details of the Tomcat class to startup, and parameters to pass</p>
                <p>There are two predefined jni workers <b>onStartup</b> and <b>onShutdown</b>. Those two workers are executed
                during startup and shutdown phase of the connector. Both must exists in the configuration to be able to start
                and shutdown Tomcat.
                </p>
                <p>
                    <table>
                        <tr>
                            <th>Property name</th>
                            <th>Default</th>
                            <th>Description</th>
                        </tr>
                        <tr>
                            <td>class</td>
                            <td>org/apache/jk/apr/TomcatStarter</td>
                            <td>class that holds the main method called to start tomcat</td>
                        </tr>
                        <tr>
                            <td>ARG</td>
                            <td/>
                            <td>Arguments to pass to main method when called</td>
                        </tr>
                        <tr>
                            <td>stdout</td>
                            <td>NULL</td>
                            <td>file to redirect Standard output from the java process</td>
                        </tr>
                        <tr>
                            <td>stderr</td>
                            <td>NULL</td>
                            <td>file to redirect Standard output from the java process </td>
                        </tr>
                    </table>
                </p>
            </subsection>
            <subsection name="ajp13">
                <p>Default worker</p>
                <p>
                    <table>
                        <tr>
                            <th>Property name</th>
                            <th>Default</th>
                            <th>Description</th>
                        </tr>
                        <tr>
                            <td>secretkey</td>
                            <td>NULL</td>
                            <td>
                                <b>Magic:</b> The secret key will be set automatically on the associated
    worker.
  </td>
                        </tr>
                        <tr>
                            <td>tomcatId</td>
                            <td/>
                            <td/>
                        </tr>
                        <tr>
                            <td>route</td>
                            <td/>
                            <td/>
                        </tr>
                        <tr>
                            <td>group</td>
                            <td/>
                            <td/>
                        </tr>
                        <tr>
                            <td>level</td>
                            <td/>
                            <td/>
                        </tr>
                        <tr>
                            <td>channel</td>
                            <td/>
                            <td/>
                        </tr>
                        <tr>
                            <td>max_connections</td>
                            <td>0 (unlimited)</td>
                            <td>Maximum number of currently used endpoints.

                                If the specified number is reached then the load balancer has the chance

                                to try another worker. This is very useful in situations when having multiple

                                servers and you wish to finer grade the lb_factor.

                            </td>
                        </tr>
                    </table>
                </p>
            </subsection>
            <subsection name="status">
                <p>Worker that outputs a page with usefull information to monitor JK2</p>
                <p>To use it add a uri component assigned to this worker</p>
            </subsection>
            <subsection name="lb">
                <p>Loadbalanced worker</p>
                <p>
                    <table>
                        <tr>
                            <th>Property name</th>
                            <th>Default</th>
                            <th>Description</th>
                        </tr>
                        <tr>
                            <td>worker</td>
                            <td/>
                            <td/>
                        </tr>
                        <tr>
                            <td>noWorkerMsg</td>
                            <td/>
                            <td/>
                        </tr>
                        <tr>
                            <td>noWorkerCode</td>
                            <td>503</td>
                            <td/>
                        </tr>
                        <tr>
                            <td>hwBalanceErr</td>
                            <td/>
                            <td/>
                        </tr>
                        <tr>
                            <td>timeout</td>
                            <td>0 (disabled)</td>
                            <td>If all the workers are in the error state, probably by Tomcat
refusing any new connections due to the overload, you can set the timeout forcing lb to wait that some
worker becomes available, instead of immediately returning error to the client. This is very useful in
situations with high peek load. The timeout should be set to the maximum application call time, but
not less then 1 second.
                            </td>
                        </tr>
                        <tr>
                            <td>attempts</td>
                            <td>3</td>
                            <td>Number of attempts that lb will try on each worker before
                            giving up.
                            </td>
                        </tr>
                        <tr>
                            <td>recovery</td>
                            <td>60 (seconds)</td>
                            <td>Time to wait before retrying to see if the worker came out
                            of the error state.
                            </td>
                        </tr>                        
                        <tr>
                            <td>stickySession</td>
                            <td>1 (true)</td>
                            <td>Sessions stick to the same worker, 1=true 0=false
                            </td>
                        </tr>
                    </table>
                </p>
            </subsection>
        </section>
        <section name="loggers">
            <p>Any connector based on jk2, at least has a default logger, that can be reached using the "logger" alias, the logger used is the more appropiate for the plataform/server combination, Apache2 under in any platform has logger.apache2 as default, IIS on his only platform uses logger.win32, and Any apache 1 install uses logger.file as default.., the config file lets you change that defaults, you can end using logger.file in IIs i.e</p>
            <p>The properties shared by all loggers are:
<table>
                    <tr>
                        <th>Property name</th>
                        <th>Default</th>
                        <th>Description</th>
                    </tr>
                    <tr>
                        <td>level</td>
                        <td>INFO</td>
                        <td>Log level. Supported: EMERG, ERROR, INFO, DEBUG</td>
                    </tr>
                </table>
            </p>
            <subsection name="logger.file">
                <p>
                    <table>
                        <tr>
                            <th>Property name</th>
                            <th>Default</th>
                            <th>Description</th>
                        </tr>
                        <tr>
                            <td>file</td>
                            <td>${serverRoot}/logs/jk2.log</td>
                            <td>
    Log file.  XXX you may be able to change this at runtime,
               to implement rolling.
  </td>
                        </tr>
                    </table>
                </p>
            </subsection>
            <subsection name="logger.win32">
                <p>logger used in the IIS server by default, it ends at native Application Event Log.</p>
            </subsection>
            <subsection name="logger.apache2">
                <p>Logger used in Apache2 servers, it normally in ends in error.log </p>
            </subsection>
    </section>
</document>
