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diff --git a/rubbos/app/tomcat-connectors-1.2.32-src/xdocs/generic_howto/workers.xml b/rubbos/app/tomcat-connectors-1.2.32-src/xdocs/generic_howto/workers.xml deleted file mode 100644 index 0c97d0c1..00000000 --- a/rubbos/app/tomcat-connectors-1.2.32-src/xdocs/generic_howto/workers.xml +++ /dev/null @@ -1,445 +0,0 @@ -<?xml version="1.0" encoding="ISO-8859-1"?> -<!DOCTYPE document [ - <!ENTITY project SYSTEM "project.xml"> -]> -<document url="workers.html"> - - &project; -<copyright> - Licensed to the Apache Software Foundation (ASF) under one or more - contributor license agreements. See the NOTICE file distributed with - this work for additional information regarding copyright ownership. - The ASF licenses this file to You under the Apache License, Version 2.0 - (the "License"); you may not use this file except in compliance with - the License. You may obtain a copy of the License at - - http://www.apache.org/licenses/LICENSE-2.0 - - Unless required by applicable law or agreed to in writing, software - distributed under the License is distributed on an "AS IS" BASIS, - WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. - See the License for the specific language governing permissions and - limitations under the License. -</copyright> -<properties> -<title>Workers HowTo</title> -<author email="hgomez@apache.org">Henri Gomez</author> -<author email="shachor@il.ibm.com">Gal Shachor</author> -<author email="mturk@apache.org">Mladen Turk</author> -<date>$Date: 2010-01-28 20:47:58 +0100 (Thu, 28 Jan 2010) $</date> -</properties> -<body> -<section name="Introduction"> -<p> -A Tomcat worker is a Tomcat instance that is waiting to execute servlets on behalf of some web server. -For example, we can have a web server such as Apache forwarding servlet requests to a -Tomcat process (the worker) running behind it. -</p> -<p> -The scenario described above is a very simple one; -in fact one can configure multiple Tomcat workers to serve servlets on -behalf of a certain web server. -The reasons for such configuration can be: -</p> -<ul> -<li> -We want different contexts to be served by different Tomcat workers to provide a -development environment where all the developers share the same web server but own a Tomcat worker of their own. -</li> -<li> -We want different virtual hosts served by different Tomcat processes to provide a -clear separation between sites belonging to different companies. -</li> -<li> -We want to provide load balancing, meaning run multiple Tomcat workers each on a -machine of its own and distribute the requests between them. -</li> -</ul> - -<p> -There are probably more reasons for having multiple workers but I guess that this list is enough... -Tomcat workers are defined in a properties file dubbed workers.properties and this tutorial -explains how to work with it. -</p> - -<p> -This document was originally part of <b>Tomcat: A Minimalistic User's Guide</b> written by Gal Shachor, -but has been split off for organisational reasons. -</p> -</section> - -<section name="Defining Workers"> -<p> -Defining workers to the Tomcat web server plugin can be done using a properties file -(a sample file named workers.properties is available in the conf/ directory). -</p> - -<p> -the file contains entries of the following form: -</p> - -<p> -<b>worker.list</b>=<a comma separated list of worker names> -</p> - -<source> - # the list of workers - worker.list= worker1, worker2 -</source> - -<p> -When starting up, the web server plugin will instantiate the workers whose name appears in the -<b>worker.list</b> property, these are also the workers to whom you can map requests. The directive can be used multiple times. -</p> - -<subsection name="Workers Type"> -<p> -Each named worker should also have a few entries to provide additional information on his behalf. -This information includes the worker's type and other related worker information. -Currently the following worker types that exists are (JK 1.2.5): -</p> - -<table> - <tr><th>Type</th><th>Description</th></tr> - <tr><td>ajp12</td><td>This worker knows how to forward requests to out-of-process Tomcat workers using the ajpv12 protocol.</td></tr> - <tr><td>ajp13</td><td>This worker knows how to forward requests to out-of-process Tomcat workers using the ajpv13 protocol.</td></tr> - <tr><td>jni</td><td>DEPRECATED: This worker knows how to forward requests to in-process Tomcat workers using JNI.</td></tr> - <tr><td>lb</td><td>This is a load-balancing worker; it knows how to provide round-robin based sticky load balancing with a certain level of fault-tolerance.</td></tr> - <tr><td>status</td><td>This is a status worker for managing load balancers.</td></tr> -</table> - -<p> -Defining workers of a certain type should be done with the following property format: -</p> - -<p> -<b>worker</b>.<b>worker name</b>.<b>type</b>=<worker type> -Where worker name is the name assigned to the worker and the worker type is one of the four types defined -in the table (a worker name may only contain any space the characters [a-zA-Z0-9\-_]). -</p> - -<source> - # Defines a worker named "local" that uses the ajpv12 protocol to forward requests to a Tomcat process. - worker.local.type=ajp12 - # Defines a worker named "remote" that uses the ajpv13 protocol to forward requests to a Tomcat process. - worker.remote.type=ajp13 - # Defines a worker named "loadbalancer" that loadbalances several Tomcat processes transparently. - worker.loadbalancer.type=lb -</source> - -</subsection> - -</section> - -<section name="Setting Worker Properties"> -<p> -After defining the workers you can also specify properties for them. -Properties can be specified in the following manner: -</p> - -<p> -worker.<worker name>.<property>=<property value> -</p> - -Each worker has a set of properties that you can set as specified in the following subsections: - -<subsection name="ajp12 Worker properties"> -<p><warn> -The <b>ajp12</b> has been <b>deprecated</b> with Tomcat 3.3.x and you should use instead -<b>ajp13</b> which is the only ajp protocol known by Tomcat 4.x and 5 and 5.5 and Tomcat 6. -</warn></p> -<p> -The ajp12 typed workers forward requests to out-of-process Tomcat workers -using the ajpv12 protocol over TCP/IP sockets. -</p> - -<p> -the ajp12 worker properties are : -</p> - -<p> -<b>host</b> property sets the host where the Tomcat worker is listening for ajp12 requests. -</p> - -<p> -<b>port</b> property sets the port where the Tomcat worker is listening for ajp12 requests -</p> - -<p> -<b>lbfactor</b> property is used when working with a load balancer worker, this is the load-balancing factor for the worker. -We'll see more on this in the <a href="../generic_howto/loadbalancers.html">lb worker</a> section. -</p> - -<source> - # worker "worker1" will talk to Tomcat listening on machine www.x.com at port 8007 using 2 lb factor - worker.worker1.host=www.x.com - worker.worker1.port=8007 - worker.worker1.lbfactor=2 -</source> - -<p> -Notes: In the ajpv12 protocol, connections are created, used and then closed at each request. -The default port for ajp12 is 8007 -</p> - -</subsection> - -<subsection name="ajp13 Worker properties"> -<p> -The ajp13 typed workers forward requests to out-of-process Tomcat workers using the ajpv13 protocol over TCP/IP sockets. -The main difference between ajpv12 and ajpv13 are that: -<ul> -<li> -ajpv13 is a more binary protocol and it tries to compress some of the request data by coding -frequently used strings as small integers. -</li> -<li> -ajpv13 reuses open sockets and leaves them open for future requests (remember when you've got a Firewall between your -web server and Tomcat). -</li> -<li> -ajpv13 has special treatment for SSL information so that the container can implement -SSL related methods such as isSecure(). -</li> -</ul> - -</p> - -<p> -You should note that Ajp13 is now the only out-process protocol supported by Tomcat 4.0.x, 4.1.x, 5.0.x, 5.5.x and 6. -</p> - - -<source> - # worker "worker2" will talk to Tomcat listening on machine www2.x.com at port 8009 using 3 lb factor - worker.worker2.host=www2.x.com - worker.worker2.port=8009 - worker.worker2.lbfactor=3 - # worker "worker2" uses connections, which will stay no more than 10mn in the connection pool - worker.worker2.connection_pool_timeout=600 - # worker "worker2" ask operating system to send KEEP-ALIVE signal on the connection - worker.worker2.socket_keepalive=1 - # mount can be used as an alternative to the JkMount directive - worker.worker2.mount=/contexta /contexta/* /contextb /contextb/* -</source> - -<p> -Notes: In the ajpv13 protocol, the default port is 8009 -</p> - -</subsection> - -<subsection name="lb Worker properties"> -<p> -The load-balancing worker does not really communicate with Tomcat workers. -Instead it is responsible for the management of several "real" workers. -This management includes: -</p> - -<ul> -<li> -Instantiating the workers in the web server. -</li> -<li> -Using the worker's load-balancing factor, perform weighed-round-robin load balancing where -high lbfactor means stronger machine (that is going to handle more requests) -</li> -<li> -Keeping requests belonging to the same session executing on the same Tomcat worker. -</li> -<li> -Identifying failed Tomcat workers, suspending requests to them and instead falling-back on -other workers managed by the lb worker. -</li> -</ul> - -<p> -The overall result is that workers managed by the same lb worker are load-balanced (based on their lbfactor and current user session) and also fall-backed so a single Tomcat process death will not "kill" the entire site. -The following table specifies some properties that the lb worker can accept: -<ul> -<li><b>balance_workers</b> is a comma separated list of workers that the load balancer need to manage. -As long as these workers should only be used via the load balancer worker, -there is no need to also put them into the worker.list property. -This directive can be used multiple times for the same load balancer.</li> -<li><b>sticky_session</b> specifies whether requests with SESSION ID's should be routed back to the same -Tomcat worker. Set sticky_session to False when Tomcat is using a Session Manager which -can persist session data across multiple instances of Tomcat. By default sticky_session is set to True.</li> -</ul> -</p> - -<source> - # The worker balance1 while use "real" workers worker1 and worker2 - worker.balance1.balance_workers=worker1, worker2 -</source> - -</subsection> - -<subsection name="Status Worker properties"> -<p> -The status worker does not communicate with Tomcat. -Instead it is responsible for the load balancer management. -</p> -<source> - # Add the status worker to the worker list - worker.list=jkstatus - # Define a 'jkstatus' worker using status - worker.jkstatus.type=status -</source> -<p>Next thing is to mount the requests to the jkstatus worker. For Apache -web servers use the:</p> -<source> - # Add the jkstatus mount point - JkMount /jkmanager/* jkstatus -</source> -<p>To obtain a higher level of security use the:</p> -<source> - # Enable the JK manager access from localhost only - <Location /jkmanager/> - JkMount jkstatus - Order deny,allow - Deny from all - Allow from 127.0.0.1 - </Location> -</source> - -</subsection> - -<subsection name="Property file macros"> -<p> -You can define "macros" in the property files. -These macros let you define properties and later on use them while -constructing other properties. -</p> - -<source> - # property example, like a network base address - mynet=194.226.31 - # Using the above macro to simplify the address definitions - # for a farm of workers. - worker.node1.host=$(mynet).11 - worker.node2.host=$(mynet).12 - worker.node3.host=$(mynet).13 -</source> - -</subsection> - -<subsection name="Hierarchical property configuration"> -<p> -Workers can reference configurations of other workers. -If worker "x" references worker "y", then it inherits all -configuration parameters from "y", except for the ones -that have explicitly been set for "x". -</p> - -<source> - # worker toe defines some default settings - worker.toe.type=ajp13 - worker.toe.socket_keepalive=true - worker.toe.connect_timeout=10000 - worker.toe.recovery_options=7 - # workers tic and tac inherit those values - worker.tic.reference=worker.toe - worker.tac.reference=worker.toe -</source> - -<p> -Please note, that the reference contains -the full prefix to the referenced configuration attributes, -not only the name of the referenced worker. -</p> - -<p> -References can be nested. Be careful to avoid loops! -</p> - -<p> -Attributes which are allowed multiple times for a single worker -can not be merged from a worker and a reference. An attribute -is only inherited from a reference, if it is not already set -for the referring worker. -</p> - -<p> -References are especially useful, when configuring load balancers. -Try to understand the following two stage references: -</p> - -<source> - # We only use one load balancer - worker.list=lb - # Let's define some defaults - worker.basic.port=8009 - worker.basic.type=ajp13 - worker.basic.socket_keepalive=true - worker.basic.connect_timeout=10000 - worker.basic.recovery_options=7 - # And we use them in two groups - worker.lb1.domain=dom1 - worker.lb1.distance=0 - worker.lb1.reference=worker.basic - worker.lb2.domain=dom2 - worker.lb2.distance=1 - worker.lb2.reference=worker.basic - # Now we configure the load balancer - worker.lb.type=lb - worker.lb.method=B - worker.lb.balanced_workers=w11,w12,w21,w22 - worker.w11.host=myhost11 - worker.w11.reference=worker.lb1 - worker.w12.host=myhost12 - worker.w12.reference=worker.lb1 - worker.w21.host=myhost21 - worker.w21.reference=worker.lb2 - worker.w22.host=myhost22 - worker.w22.reference=worker.lb2 -</source> - -</subsection> - -</section> - -<section name="A sample worker.properties"> -<p> -Since coping with worker.properties on your own is not an easy thing to do, -a sample worker.properties file is bundled along JK. -</p> - -<p> -You could also find here a sample workers.properties defining : -</p> - -<ul> -<li> -An ajp12 worker that used the host localhost and the port 8007 -</li> -<li> -An ajp13 worker that used the host localhost and the port 8008 -</li> -<li> -An lb worker that load balance the ajp12 and ajp13 workers -</li> -</ul> - -<source> - # Define 3 workers, 2 real workers using ajp12, ajp13, the last one being a loadbalancing worker - worker.list=worker1, worker2, worker3 - # Set properties for worker1 (ajp12) - worker.worker1.type=ajp12 - worker.worker1.host=localhost - worker.worker1.port=8007 - worker.worker1.lbfactor=1 - # Set properties for worker2 (ajp13) - worker.worker2.type=ajp13 - worker.worker2.host=localhost - worker.worker2.port=8009 - worker.worker2.lbfactor=1 - worker.worker2.connection_pool_timeout=600 - worker.worker2.socket_keepalive=1 - worker.worker2.socket_timeout=60 - # Set properties for worker3 (lb) which use worker1 and worker2 - worker.worker3.balance_workers=worker1,worker2 -</source> - -</section> -</body> -</document> |