使用apache2 jboss集群

环境：OS ubuntu， jdk 5.0，jboss4.0.4GA
1. 安装apache2。 sudo aptitude install apache2
2. 安装mod_jk , sudo aptitude install libapache2-mod-jk
3. 配置apache的loadblance

• 修改/etc/apache2/httpd.conf 增加下面这段文字。

java 代码

# Include mod_jk's specific configuration file
Include conf.d/mod-jk.conf

• 建立/etc/apache2/conf.d/mod-jk.conf,如果没有conf.d文件夹的话，就手工建。mod-jk.conf如下：

java 代码

# Where to find workers.properties
JkWorkersFile conf/workers.properties

# Where to put jk logs
JkLogFile logs/mod_jk.log

# Set the jk log level [debug/error/info]
JkLogLevel info

# Select the log format
JkLogStampFormat  "[%a %b %d %H:%M:%S %Y]"

# JkOptions indicates to send SSK KEY SIZE
JkOptions +ForwardKeySize +ForwardURICompat -ForwardDirectories

# JkRequestLogFormat
JkRequestLogFormat "%w %V %T"

# Mount your applications
JkMount /rss-server loadbalancer
JkMount /rss-server/* loadbalancer

# You can use external file for mount points.
# It will be checked for updates each 60 seconds.
# The format of the file is: /url=worker
# /examples/*=loadbalancer
#JkMountFile conf/uriworkermap.properites

# Add shared memory.
# This directive is present with 1.2.10 and
# later versions of mod_jk, and is needed for
# for load balancing to work properly
JkShmFile logs/jk.shm

# Add jkstatus for managing runtime data
<Location /jkstatus/>
    JkMount status
    Order deny,allow
    Deny from all
    Allow from 127.0.0.1
</Location>
#<VirtualHost *:443>
#    JkMount /cas loadbalancer
#    JkMount /cas/* loadbalancer
#</VirtualHost>

上面定义works所放的文件地址，mount的网站（rss-server）。注意：这里我们定义了log文件的地址是 logs/mod_jk.log，如果没有logs目录的话，需要建一个，要不到后面apache起不来了。浪费了相当一段时间在这里。

• 建立conf/workers.properties文件，如下：

java 代码

# Define list of workers that will be used
# for mapping requests
# The configuration directives are valid
# for the mod_jk version 1.2.18 and later
#
worker.list=loadbalancer,status

# Define Node1
# modify the host as your host IP or DNS name.
worker.node1.port=8009
worker.node1.host=192.168.1.119
worker.node1.type=ajp13
worker.node1.lbfactor=1
# worker.node1.connection_pool_size=10 (1)

# Define Node2
# modify the host as your host IP or DNS name.
worker.node2.port=8009
worker.node2.host= 192.168.1.102
worker.node2.type=ajp13
worker.node2.lbfactor=1
# worker.node1.connection_pool_size=10 (1)

# Define Node3
# modify the host as your host IP or DNS name.
#worker.node3.port=8009
#worker.node3.host= 192.168.1.119
#worker.node3.type=ajp13
#worker.node3.lbfactor=1
# worker.node3.connection_pool_size=10 (1)

# Load-balancing behaviour
worker.loadbalancer.type=lb
worker.loadbalancer.balanced_workers=node1,node2

# Status worker for managing load balancer
worker.status.type=status

我们定义了node1，node2用于 loadbalance。配置好ip和mod-jk的port。Apache端的配置就差不多了。
4. Jboss tomcat配置

• 修改JBOSS_HOME/server/all/deploy/jbossweb-tomcat50.sar/server.xml 如下：

xml 代码

<Engine name="jboss.web" defaultHost="localhost" jvmRoute="node1">
... ...
</Engine>

在另一台机上做同样的修改，替换node1成node2。

• 修改JBOSS_HOME/server/all/deploy/jbossweb-tomcat50.sar/META-INF/jboss-service.xml 如下：

xml 代码

<attribute name="UseJK">true</attribute>

其他node的jboss也需要同样的修改。

• 配置http session 状态复制。修改deploy/tc5-cluster.sar/META-INF/jboss-service.xml (这里已经是ok的。不需要再配置)，让你的web application能够支持分布式，修改你的web.xml， 如下：

xml 代码

<?xml version="1.0"?>
<web-app  xmlns="http://java.sun.com/xml/ns/j2ee"
          xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
          xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee
                              http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd"
          version="2.4">
    <distributable/>
    <!-- ... -->
</web-app>

创建一个jboss-web.xml文件， 如下：

xml 代码

<jboss-web>
    <replication-config>
        <replication-trigger>SET_AND_NON_PRIMITIVE_GET</replication-trigger>
        <replication-granularity>SESSION</replication-granularity>
    </replication-config>
</jboss-web>

其中replication-trigger是指定哪些操作引发session的版本更新，它的取值有：

SET_AND_GET        
SET_AND_NON_PRIMITIVE_GET
SET

ok. 这样的话就基本完成了。
5. 其他设置

• 改变cluster广播地址。$JBOSS_HOME/server/all/deploy/tc5-cluster.sar/META-INF/jboss-service.xml. 改变 "<UDP mcast_addr="${jboss.partition.udpGroup:230.1.2.7}""属性。

• If you have multi network interfaces, you should specify which will be used as following

  ./run.sh -b 192.168.1.102

  Please make sure the multi-cast address of cas cluster should be unique, which means other cluster group's multi-cast address shouldn't be the same as cas cluster.

• 分布式热部署(distributable hot deploy)
  
      在一个节点很多的cluster中，如果部署应用的时候必须 把程序文件拷贝到每个机器上的话，那实在太愚蠢了，幸好通过all启动的jboss自动支持分布式热部署。把支持cluster的应用（通常需要打包成 war文件），放到%jboss%\server\all\farm下，那么处于同一cluster中的其他节点会自动下载并且部署，jboss把这个称 为Farm deploy。

参考：Jboss cluster 文档
         http://www.huihoo.com/jboss/clustering/jboss-4.0.2.html