JBoss 系列五十：使用Apache httpd(mod_jk)和JBoss构架高可用集群环境
概述
前面 JBoss 系列二：使用Apache httpd(mod_cluster)和JBoss构架高可用集群环境中我们介绍了企业应用的目的的目的，负载均衡，容错等，并通过Apache httpd(mod_cluster)和JBoss构架高可用集群环境，我们这里在原有的环境中将mod_cluster换成mod_jk，其架构如下图所示：
本方案是在开源Linux操作系统Fedora 15上进行，我们列出本方案使用的硬件和软件，三台物理机器，内存4GB或以上，安装Fedora 15后IP地址分别为10.66.192.48，10.66.192.231，10.66.192.232，我们分别对这三台物理机器做相应的安装如下：
- 10.66.192.231 – 安装JDK 1.6，JBoss 7，JBoss节点名称为node1
- 10.66.192.232 – 安装JDK 1.6，JBoss 7，JBoss节点名称为node2
- 10.66.192.48 – 安装Apache httpd，mod_jk
下载mod_jk相关安装包
从 http://tomcat.apache.org/download-connectors.cgi下载mod_jk.so包到本地（注意选择适合自己操作系统对应httpd的包）。
安装 Apache httpd
请参照系列一 Apache httpd 安装（ http://blog.csdn.net/kylinsoong/article/details/12291173）
Apache httpd端配置
编辑httpd/conf/httpd.conf，让httpd监听在10.66.192.48:80上：
Listen 10.66.192.48:80拷贝mod_jk.so文件到httpd/modules目录：
cp mod_jk.so /etc/httpd/modules在httpd/conf.d下创建mod_jk.conf文件，编辑内容如下：
# Load mod_jk module
# Specify the filename of the mod_jk lib
LoadModule jk_module modules/mod_jk.so
# Where to find workers.properties
JkWorkersFile conf/workers.properties
# 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.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 /application/* loadbalancer
# 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>在httpd/conf下创建workers.properties，并添加如下内容：
# Define list of workers that will be used # for mapping requests worker.list=loadbalancer,status # Define Node1 # modify the host as your host IP or DNS name. worker.node1.port=8009 worker.node1.host=10.66.192.231 worker.node1.type=ajp13 worker.node1.ping_mode=A worker.node1.lbfactor=1 # Define Node2 # modify the host as your host IP or DNS name. worker.node2.port=8009 worker.node2.host=10.66.192.232 worker.node2.type=ajp13 worker.node2.ping_mode=A worker.node2.lbfactor=1 # Load-balancing behavior worker.loadbalancer.type=lb worker.loadbalancer.balance_workers=node1,node2 worker.loadbalancer.sticky_session=1 # Status worker for managing load balancer worker.status.type=status在httpd/conf下创建uriworkermap.properties，并添加如下内容：
# Simple worker configuration file # Mount the Servlet context to the ajp13 worker /jmx-console=loadbalancer /jmx-console/*=loadbalancer /web-console=loadbalancer /web-console/*=loadbalancer #/printSession=loadbalancer #/printSession/*=loadbalancer配置完成后重启Apache httpd，如果启动显示成功表明配置正确。
JBoss端配置
分别启动10.66.192.231，10.66.192.232 JBoss,到管理界面，Profile -> General Configuration -> System Properties,单击添加按钮，添加两组变量jvmRoute=node1,UseJK=true到10.66.192.231,以及jvmRoute=node2,UseJK=true到10.66.192.232.添加完成后，依次重启两个节点：
./standalone.sh -c standalone-ha.xml -b 10.66.192.231 -bmanagement 10.66.192.231 -u 239.255.100.100 -Djboss.node.name=node1
./standalone.sh -c standalone-ha.xml -b 10.66.192.232 -bmanagement 10.66.192.232 -u 239.255.100.100 -Djboss.node.name=node2
结束
至此，配置结束，我们可以部署测试应用测试高可用，负责均衡等，类似于 JBoss 系列二：使用Apache httpd(mod_cluster)和JBoss构架高可用集群环境