tomcat之负载均衡（apache反响代理tomcat）
基于mod_proxy模块
配置内容如下：
准备工作--》检查模块
# httpd -D DUMP_MODULES
……………………
proxy_module (shared)
proxy_balancer_module (shared)
proxy_ftp_module (shared)
proxy_http_module (shared)
proxy_connect_module (shared)
……………………
proxy_module (shared)
proxy_balancer_module (shared)
proxy_ftp_module (shared)
proxy_http_module (shared)
proxy_connect_module (shared)
前端apache配置内容-->192.168.9.130
# cat /etc/httpd/conf.d/proxy_tomcat.conf
ProxyVia On
ProxyVia On
#关闭正向代理
ProxyRequests Off
ProxyRequests Off
#前端向后端转发的时候支持虚拟主机
ProxyPreserveHost On
<Proxy balancer : / /lbcluster >
ProxyPreserveHost On
<Proxy balancer : / /lbcluster >
#这里基于HTTP/1.1协议,也可以基于AJP/1.3,需要修改对应的后端tomcat服务器的
连接器属性，
端口也要和tomcat中定义的一致.
BalancerMember http : / / 192 . 168 . 6 . 128 : 80 loadfactor = 1
BalancerMember http : / / 192 . 168 . 6 . 129 : 80 loadfactor = 1
#设定负载均衡算法(byrequests基于权重，类似haproxy的roundrobin)(bybusiness基于当前负载情况，类似于haproxy的leastconn最少连接)(bytraffic基于后端流量)
ProxySet lbmethod = byrequests
< / Proxy >
#如果访问的是http://ip/lbmanager,则不代理，balancer-manager可以保留代理状态信息
< Location / lbmanager >
#强制所有匹配的文件被一个指定的处理器处理
SetHandler balancer - manager
Proxypass !
Order Deny,Allow
Allow from all
< / Location >
#代理集群
#代理( 这里代理后的路径最后有个/，一定不能省略 )
ProxyPass / balancer : / / lbcluster/
#作用在于原请求之后追加上redirect的路径
ProxyPassReverse / balancer : / / lbcluster/
#2.2控制机制，2.4使用Require all granted
< Location * >
Order allow,deny
Allow from all
< / Location >
< Location / >
Order allow,deny
Allow from all
< / Location >
BalancerMember http : / / 192 . 168 . 6 . 128 : 80 loadfactor = 1
BalancerMember http : / / 192 . 168 . 6 . 129 : 80 loadfactor = 1
#设定负载均衡算法(byrequests基于权重，类似haproxy的roundrobin)(bybusiness基于当前负载情况，类似于haproxy的leastconn最少连接)(bytraffic基于后端流量)
ProxySet lbmethod = byrequests
< / Proxy >
#如果访问的是http://ip/lbmanager,则不代理，balancer-manager可以保留代理状态信息
< Location / lbmanager >
#强制所有匹配的文件被一个指定的处理器处理
SetHandler balancer - manager
Proxypass !
Order Deny,Allow
Allow from all
< / Location >
#代理集群
#代理( 这里代理后的路径最后有个/，一定不能省略 )
ProxyPass / balancer : / / lbcluster/
#作用在于原请求之后追加上redirect的路径
ProxyPassReverse / balancer : / / lbcluster/
#2.2控制机制，2.4使用Require all granted
< Location * >
Order allow,deny
Allow from all
< / Location >
< Location / >
Order allow,deny
Allow from all
< / Location >
后端tomcat配置-->
所有节点--》
#vim server.xml
<Connector port
=
"80" protocol
=
"HTTP/1.1"
connectionTimeout = "20000"
redirectPort = "8443" / >
connectionTimeout = "20000"
redirectPort = "8443" / >
#mkdir -pv $CATALINA_HOME/webapps/testapp/WEB-INF/{lib,classes}
添加分布式配置文件
#cp
$CATALINA_HOME/conf/web.xml
$CATALINA_HOME/webapps/testapp/WEB-INF
#vim
$CATALINA_HOME/webapps/testapp/WEB-INF/web.xml
添加
<distributable
/
>
节点A--》
192
.
168
.
6
.
128
在server.xml的Engine段中添加如下内容（也可以在Host中添加），这里主要修改本节点心跳地址和端口
#vim server.xml
<Cluster className
=
"org.apache.catalina.ha.tcp.SimpleTcpCluster" channelSendOptions
=
"8"
>
<Manager className = "org.apache.catalina.ha.session.DeltaManager" expireSessionsOnShutdown = "false" notifyListenersOnReplication = "true" / >
<Channel className = "org.apache.catalina.tribes.group.GroupChannel" >
<Membership className = "org.apache.catalina.tribes.membership.McastService" address = "224.0.0.4" port = "45564" frequency = "500" dropTime = "3000" / >
<Receiver className = "org.apache.catalina.tribes.transport.nio.NioReceiver" address = "192.168.6.128" port = "4000" autoBind = "100" selectorTimeout = "5000" maxThreads = "6" / >
<Sender className = "org.apache.catalina.tribes.transport.ReplicationTransmitter" >
<Transport className = "org.apache.catalina.tribes.transport.nio.PooledParallelSender" / >
< /Sender >
<Interceptor className = "org.apache.catalina.tribes.group.interceptors.TcpFailureDetector" / >
<Interceptor className = "org.apache.catalina.tribes.group.interceptors.MessageDispatch15Interceptor" / >
<Interceptor className = "org.apache.catalina.tribes.group.interceptors.ThroughputInterceptor" / >
< /Channel >
<Valve className = "org.apache.catalina.ha.tcp.ReplicationValve" filter = "" / >
<Valve className = "org.apache.catalina.ha.session.JvmRouteBinderValve" / >
< ! -- <Deployer className = "org.apache.catalina.ha.deploy.FarmWarDeployer" tempDir = "/tmp/war-temp/" deployDir = "/tmp/war-deploy/" watchDir = "/tmp/war-listen/" watchEnabled = "false" / > -- >
<ClusterListener className = "org.apache.catalina.ha.session.JvmRouteSessionIDBinderListener" / >
<ClusterListener className = "org.apache.catalina.ha.session.ClusterSessionListener" / >
< /Cluster >
<Manager className = "org.apache.catalina.ha.session.DeltaManager" expireSessionsOnShutdown = "false" notifyListenersOnReplication = "true" / >
<Channel className = "org.apache.catalina.tribes.group.GroupChannel" >
<Membership className = "org.apache.catalina.tribes.membership.McastService" address = "224.0.0.4" port = "45564" frequency = "500" dropTime = "3000" / >
<Receiver className = "org.apache.catalina.tribes.transport.nio.NioReceiver" address = "192.168.6.128" port = "4000" autoBind = "100" selectorTimeout = "5000" maxThreads = "6" / >
<Sender className = "org.apache.catalina.tribes.transport.ReplicationTransmitter" >
<Transport className = "org.apache.catalina.tribes.transport.nio.PooledParallelSender" / >
< /Sender >
<Interceptor className = "org.apache.catalina.tribes.group.interceptors.TcpFailureDetector" / >
<Interceptor className = "org.apache.catalina.tribes.group.interceptors.MessageDispatch15Interceptor" / >
<Interceptor className = "org.apache.catalina.tribes.group.interceptors.ThroughputInterceptor" / >
< /Channel >
<Valve className = "org.apache.catalina.ha.tcp.ReplicationValve" filter = "" / >
<Valve className = "org.apache.catalina.ha.session.JvmRouteBinderValve" / >
< ! -- <Deployer className = "org.apache.catalina.ha.deploy.FarmWarDeployer" tempDir = "/tmp/war-temp/" deployDir = "/tmp/war-deploy/" watchDir = "/tmp/war-listen/" watchEnabled = "false" / > -- >
<ClusterListener className = "org.apache.catalina.ha.session.JvmRouteSessionIDBinderListener" / >
<ClusterListener className = "org.apache.catalina.ha.session.ClusterSessionListener" / >
< /Cluster >
#vim $CATALINA_HOME/webapps/testapp/index.jsp
<
%@ page language
=
"java"
%
>
<html >
<head > <title >TomcatA < /title > < /head >
<body >
<h1 > <font color = "red" >TomcatA < /font > < /h1 >
<table align = "centre" border = "1" >
<tr >
<td >Session ID < /td >
< % session.setAttribute( "abc", "abc"); % >
<td > < % = session.getId() % > < /td >
< /tr >
<tr >
<td >Created on < /td >
<td > < % = session.getCreationTime() % > < /td >
< /tr >
< /table >
< /body >
< /html >
<html >
<head > <title >TomcatA < /title > < /head >
<body >
<h1 > <font color = "red" >TomcatA < /font > < /h1 >
<table align = "centre" border = "1" >
<tr >
<td >Session ID < /td >
< % session.setAttribute( "abc", "abc"); % >
<td > < % = session.getId() % > < /td >
< /tr >
<tr >
<td >Created on < /td >
<td > < % = session.getCreationTime() % > < /td >
< /tr >
< /table >
< /body >
< /html >
节点B--》
192
.
168
.
6
.
129
在server.xml的Engine段中添加如下内容（也可以在Host中添加）
#vim server.xml
<Cluster className
=
"org.apache.catalina.ha.tcp.SimpleTcpCluster" channelSendOptions
=
"8"
>
<Manager className = "org.apache.catalina.ha.session.DeltaManager" expireSessionsOnShutdown = "false" notifyListenersOnReplication = "true" / >
<Channel className = "org.apache.catalina.tribes.group.GroupChannel" >
<Membership className = "org.apache.catalina.tribes.membership.McastService" address = "224.0.0.4" port = "45564" frequency = "500" dropTime = "3000" / >
<Receiver className = "org.apache.catalina.tribes.transport.nio.NioReceiver" address = "192.168.6.129" port = "4001" autoBind = "100" selectorTimeout = "5000" maxThreads = "6" / >
<Sender className = "org.apache.catalina.tribes.transport.ReplicationTransmitter" >
<Transport className = "org.apache.catalina.tribes.transport.nio.PooledParallelSender" / >
< /Sender >
<Interceptor className = "org.apache.catalina.tribes.group.interceptors.TcpFailureDetector" / >
<Interceptor className = "org.apache.catalina.tribes.group.interceptors.MessageDispatch15Interceptor" / >
<Interceptor className = "org.apache.catalina.tribes.group.interceptors.ThroughputInterceptor" / >
< /Channel >
<Valve className = "org.apache.catalina.ha.tcp.ReplicationValve" filter = "" / >
<Valve className = "org.apache.catalina.ha.session.JvmRouteBinderValve" / >
< ! -- <Deployer className = "org.apache.catalina.ha.deploy.FarmWarDeployer" tempDir = "/tmp/war-temp/" deployDir = "/tmp/war-deploy/" watchDir = "/tmp/war-listen/" watchEnabled = "false" / > -- >
<ClusterListener className = "org.apache.catalina.ha.session.JvmRouteSessionIDBinderListener" / >
<ClusterListener className = "org.apache.catalina.ha.session.ClusterSessionListener" / >
< /Cluster >
<Manager className = "org.apache.catalina.ha.session.DeltaManager" expireSessionsOnShutdown = "false" notifyListenersOnReplication = "true" / >
<Channel className = "org.apache.catalina.tribes.group.GroupChannel" >
<Membership className = "org.apache.catalina.tribes.membership.McastService" address = "224.0.0.4" port = "45564" frequency = "500" dropTime = "3000" / >
<Receiver className = "org.apache.catalina.tribes.transport.nio.NioReceiver" address = "192.168.6.129" port = "4001" autoBind = "100" selectorTimeout = "5000" maxThreads = "6" / >
<Sender className = "org.apache.catalina.tribes.transport.ReplicationTransmitter" >
<Transport className = "org.apache.catalina.tribes.transport.nio.PooledParallelSender" / >
< /Sender >
<Interceptor className = "org.apache.catalina.tribes.group.interceptors.TcpFailureDetector" / >
<Interceptor className = "org.apache.catalina.tribes.group.interceptors.MessageDispatch15Interceptor" / >
<Interceptor className = "org.apache.catalina.tribes.group.interceptors.ThroughputInterceptor" / >
< /Channel >
<Valve className = "org.apache.catalina.ha.tcp.ReplicationValve" filter = "" / >
<Valve className = "org.apache.catalina.ha.session.JvmRouteBinderValve" / >
< ! -- <Deployer className = "org.apache.catalina.ha.deploy.FarmWarDeployer" tempDir = "/tmp/war-temp/" deployDir = "/tmp/war-deploy/" watchDir = "/tmp/war-listen/" watchEnabled = "false" / > -- >
<ClusterListener className = "org.apache.catalina.ha.session.JvmRouteSessionIDBinderListener" / >
<ClusterListener className = "org.apache.catalina.ha.session.ClusterSessionListener" / >
< /Cluster >
#vim $CATALINA_HOME/webapps/testapp/index.jsp
<
%@ page language
=
"java"
%
>
<html >
<head > <title >TomcatB < /title > < /head >
<body >
<h1 > <font color = "blue" >TomcatB < /font > < /h1 >
<table align = "centre" border = "1" >
<tr >
<td >Session ID < /td >
< % session.setAttribute( "abc", "abc"); % >
<td > < % = session.getId() % > < /td >
< /tr >
<tr >
<td >Created on < /td >
<td > < % = session.getCreationTime() % > < /td >
< /tr >
< /table >
< /body >
< /html >
<html >
<head > <title >TomcatB < /title > < /head >
<body >
<h1 > <font color = "blue" >TomcatB < /font > < /h1 >
<table align = "centre" border = "1" >
<tr >
<td >Session ID < /td >
< % session.setAttribute( "abc", "abc"); % >
<td > < % = session.getId() % > < /td >
< /tr >
<tr >
<td >Created on < /td >
<td > < % = session.getCreationTime() % > < /td >
< /tr >
< /table >
< /body >
< /html >
测试--》访问http://192.168.9.130/testapp
如果正常，则会刷新过程中分别显示TomcatA和TomcatB，但是会话一致
说实话，我做到最后会话不知为什么不能保持，日志中已经互相检测到，但是会话疑似没有复制，这个
（暂留）
中间遇到的问题如下：
Deployer className选项可能会造成以下错误
严重
: FarmWarDeployer can only work as host cluster subelement
!
如果配置完毕后，发现不能启动tomcat，则需要将组播地址添加到路由里，并添加到/etc/crontab
route add
-net
224.
0.
0.
4 netmask
255.
255.
255.
255 dev eth0
基于mod_jk模块（暂留）
准备工作--》
1、 为了避免用户直接访问后端Tomcat实例，影响负载均衡的效果，建议在Tomcat 7的各实例上禁用HTTP/1.1连接器。
2、为每一个Tomcat 7实例的引擎添加jvmRoute参数，并通过其为当前引擎设置全局惟一标识符。如下所示。需要注意的是，每一个实例的jvmRoute的值均不能相同。
3、前端apache如果使用的是mod_jk模式，则tomcat引擎一定要定义jvmroute参数；如果前端apache使用的是mod_proxy模式，则不需要定义。
tomcat引擎的开头示例如下--->
<Engine name
=”Standalone” defaultHost
=”localhost”
jvmRoute=” TomcatA ”
>
配置过程--》
配置apache，修改/etc/httpd/extra/httpd-jk.conf为如下内容：
LoadModule jk_module modules
/mod_jk.so
JkWorkersFile /etc /httpd /extra /workers.properties
JkLogFile logs /mod_jk.log
JkLogLevel debug
#访问根下的任意文件,都转到集群1上
JkMount / * lbcluster1
#访问根下的jkstatus,都转到stat1上
JkMount /jkstatus / stat1
JkWorkersFile /etc /httpd /extra /workers.properties
JkLogFile logs /mod_jk.log
JkLogLevel debug
#访问根下的任意文件,都转到集群1上
JkMount / * lbcluster1
#访问根下的jkstatus,都转到stat1上
JkMount /jkstatus / stat1
编辑/etc/httpd/extra/workers.properties，添加如下内容：
worker.list
= lbcluster1,stat1
#实例类型
worker.TomcatA.type = ajp13
#实例内定义的虚拟主机的访问ip
worker.TomcatA.host = 172. 16. 100. 1
#实例与连接器之间的端口
worker.TomcatA.port = 8009
#实例权重
worker.TomcatA.lbfactor = 5
worker.TomcatB.type = ajp13
worker.TomcatB.host = 172. 16. 100. 2
worker.TomcatB.port = 8009
worker.TomcatB.lbfactor = 5
#集群类型
worker.lbcluster1.type = lb
#会话绑定
worker.lbcluster1.sticky_session = 1
#调度方法
worker.lbcluster1.method = R
#集群里含有的实例
worker.lbcluster1.balance_workers = TomcatA, TomcatB
worker.stat1.type = status
#实例类型
worker.TomcatA.type = ajp13
#实例内定义的虚拟主机的访问ip
worker.TomcatA.host = 172. 16. 100. 1
#实例与连接器之间的端口
worker.TomcatA.port = 8009
#实例权重
worker.TomcatA.lbfactor = 5
worker.TomcatB.type = ajp13
worker.TomcatB.host = 172. 16. 100. 2
worker.TomcatB.port = 8009
worker.TomcatB.lbfactor = 5
#集群类型
worker.lbcluster1.type = lb
#会话绑定
worker.lbcluster1.sticky_session = 1
#调度方法
worker.lbcluster1.method = R
#集群里含有的实例
worker.lbcluster1.balance_workers = TomcatA, TomcatB
worker.stat1.type = status