Apache是一個強大的Web服務器在處理靜態頁面、處理大量網絡客戶請求、支持服務的種類以及可配置方面都有優勢，高速並且強壯。但是沒有JSP/Servlet的解析能力。整合Apache和Tomcat可以看作是用Tomcat做Apache的jsp/servlet解析插件，將兩者優勢結合起來。不過Tomcat作為一個Web服務器，本身具備了基本的Web服務功能，在SUN的力推下，將來或許越來越強壯到不需要借助Apache優勢的地步。
Tomcat是一個免費的開放源代碼的Web 應用服務器，屬於輕量級應用服務器，在中小型系統和並發訪問用戶不是很多的場合下被普遍使用，是開發和調試JSP 程序的首選。Tomcat 很受廣大程序員的喜歡，因為它運行時占用的系統資源小，擴展性好，支持負載平衡與郵件服務等開發應用系統常用的功能；而且它還在不斷的改進和完善中，任何一個感興趣的程序員都可以更改它或在其中加入新的功能。
Apache與tomcat的異同：
apache支持靜態頁，tomcat支持動態的，比如servlet等。
一般使用apache+tomcat的話，apache只是作為一個轉發，對jsp的處理是由tomcat來處理的。
apache可以支持php\cgi\perl,但是要使用java的話，你需要tomcat在apache后台支撐，將java請求由apache轉發給tomcat處理。
apache是web服務器,Tomcat是應用（java）服務器，它只是一個servlet(jsp也翻譯成servlet)容器，可以認為是apache的擴展，但是可以獨立於apache運行。
Apache是專門用了提供HTTP服務的，以及相關配置的（例如虛擬主機、URL轉發等等）。
Tomcat是Apache組織在符合J2EE的JSP、Servlet標准下開發的一個JSP服務器；
Apache與tomcat整合的好處：
如果客戶端請求的是靜態頁面，則只需要Apache服務器響應請求。
如果客戶端請求動態頁面，則是Tomcat服務器響應請求。
因為jsp是服務器端解釋代碼的，這樣整合就可以減少Tomcat的服務開銷。
一.環境與功能說明
前端：apache配置負載均衡、反向代理（mod_jk模塊）
后端：tomcat服務器
前端高可用：通過keepalived實現
系統版本：CentOS 6.4_x86_64（最小化）
apache版本：httpd-2.4.9
arp版本：apr-1.4.6
apr-util版本：apr-util-1.4.1
tomcat版本：apache-tomcat-7.0.53
Jdk版本：jdk-7u40-linux-x64
tomcat-commectors版本：tomcat-connectors-1.2.40
keepalived版本：keepalived-1.2.7-3.el6.x86_64(使用yum安裝)
二.安裝與配置apache服務器（172.16.10.72、172.16.10.75執行同樣的安裝與配置，這里只演示一次）
1.安裝編譯工具和依賴包
yum groupinstall "Development Tools" "Development Libraries" –y
2.下載軟件包
yum -y install wget
wget http://mirror.esocc.com/apache//httpd/httpd-2.4.9.tar.gz
wget http://mirrors.axint.net/apache//apr/apr-1.4.6.tar.gz
wget http://mirrors.axint.net/apache//apr/apr-util-1.4.1.tar.gz
3.安裝apache
3.1.安裝apr和apr-tuil
httpd-2.4.9需要較新版本的apr和apr-util，因此需要事先對其進行升級。升級方式有兩種，一種是通過源代碼編譯安裝，一種是直接升級rpm包。以下是采用前者進行安裝：
# tar xf apr-1.4.6.tar.gz # tar xf apr-util-1.4.1.tar.gz # cd apr-1.4.6 # ./configure --prefix=/usr/local/apr # make # make install # cd .. # cd apr-util-1.4.1 # ./configure --prefix=/usr/local/apr-util --with-apr=/usr/local/apr # make # make install # cd ..
3.2.安裝http-2.4.9
# ./configure --prefix=/usr/local/apache --sysconfdir=/etc/httpd24 --enable-so --enable-ssl --enable-cgi --enable-rewrite --with-zlib --with-pcre --with-apr=/usr/local/apr --with-apr-util=/usr/local/apr-util/ --enable-modules=most --enable-mpms-shared=all # make && make install
4.配置SysV服務腳本/etc/init.d/httpd
# cp build/rpm/httpd.init /etc/init.d/httpd #修改如下內容：
# vi /etc/init.d/httpd httpd=${HTTPD-/usr/local/apache/bin/httpd} pidfile=${PIDFILE-/usr/local/apache/logs/${prog}.pid} lockfile=${LOCKFILE-/var/lock/subsys/${prog}} RETVAL=0 # check for 1.3 configuration check13 () { CONFFILE=/etc/httpd24/httpd.conf
#修改環境變量並把Httpd加入到系統服務
# echo "PATH=/usr/local/apache/bin:$PATH" >> /etc/profile.d/http.sh
# . /etc/profile.d/http.sh
# ln -s /usr/local/apache/include/ /usr/include/httpd
# chkconfig --add httpd
5.安裝tomcat-connectors
# wget http://apache.fayea.com/apache-mirror/tomcat/tomcat-connectors/jk/tomcat-connectors-1.2.40-src.tar.gz
# tar xf tomcat-connectors-1.2.40-src.tar.gz # cd tomcat-connectors-1.2.40-src/native/ # ./configure --with-apxs=/usr/local/apache/bin/apxs # make # make install
安裝完成后會生成如下文件
# ls /usr/local/apache/modules/|grep 'mod_jk' mod_jk.so
啟動httpd服務
# service httpd start
執行./configure --with-apxs=/usr/local/apache/bin/apxs時可能會遇到以下報錯：
need to check for Perl first, apxs depends on it...
checking for perl... /usr/bin/perl
could not find /usr/local/apache/bin/apxs
configure: error: You must specify a valid --with-apxs path
解法辦法：
vi /usr/local/apache/bin/apxs
把第一行改成：#!/usr/bin/perl -w
另外檢查系統中是否已經安裝過perl，如果沒有安裝，用yum安裝即可。
三.安裝與配置tomcat服務器（172.16.10.61、172.16.10.62執行同樣的安裝，這里只演示一次）
1.安裝JDK
下載地址：http://download.oracle.com/
# rpm -ivh jdk-7u40-linux-x64.rpm # vim /etc/profile.d/java.sh export JAVA_HOME=/usr/java/latest export PATH=$JAVA_HOME/bin:$PATH # . /etc/profile.d/java.sh # java -version java version "1.7.0_40" Java(TM) SE Runtime Environment (build 1.7.0_40-b43) Java HotSpot(TM) 64-Bit Server VM (build 24.0-b56, mixed mode)
2.安裝Tomcat
下載地址：http://apache.fayea.com/apache-mirror/tomcat/tomcat-7/v7.0.53/bin/apache-tomcat-7.0.53.tar.gz
# tar xf apache-tomcat-7.0.53.tar.gz -C /usr/local/ # cd /usr/local/ # ln -s apache-tomcat-7.0.53 tomcat # vim /etc/profile.d/tomcat.sh export CATALINA_HOME=/usr/local/tomcat export PATH=$CATALINA_HOME/bin:$PATH # . /etc/profile.d/tomcat.sh # /usr/local/tomcat/bin/catalina.sh version Using CATALINA_BASE: /usr/local/tomcat Using CATALINA_HOME: /usr/local/tomcat Using CATALINA_TMPDIR: /usr/local/tomcat/temp Using JRE_HOME: /usr/java/latest Using CLASSPATH: /usr/local/tomcat/bin/bootstrap.jar:/usr/local/tomcat/bin/tomcat-juli.jar Server version: Apache Tomcat/7.0.53 Server built: Mar 25 2014 06:20:16 Server number: 7.0.53.0 OS Name: Linux OS Version: 2.6.32-279.el6.x86_64 Architecture: amd64 JVM Version: 1.7.0_40-b43 JVM Vendor: Oracle Corporation
3.啟動Tomcat服務並訪問測試，默認訪問端口為8080：
# /usr/local/tomcat/bin/catalina.sh start Using CATALINA_BASE: /usr/local/tomcat Using CATALINA_HOME: /usr/local/tomcat Using CATALINA_TMPDIR: /usr/local/tomcat/temp Using JRE_HOME: /usr/java/latest Using CLASSPATH: /usr/local/tomcat/bin/bootstrap.jar:/usr/local/tomcat/bin/tomcat-juli.jar Tomcat started. # ss -antpl | grep 8080
0 100 :::8080 :::* users:(("java",1299,42))
4.開啟Tomcat管理及狀態頁面
# vim /usr/local/tomcat/conf/tomcat-users.xml(在</tomcat-users>標簽上一行添加如下兩行) <role rolename="manager-gui"/>
<user username="tomcat" password="tomcat" roles="manager-gui"/> #后台管理頁面登錄名及密碼均為tomcat # /usr/local/tomcat/bin/catalina.sh stop # /usr/local/tomcat/bin/catalina.sh start
5.訪問Tomcat后台管理
四.配置Apache使用mod_jk模塊實現代理及負載均衡
1.編輯Apache主配置文件，實現代理功能（172.16.10.72）
echo "Include /etc/httpd24/extra/mod_jk.conf" >> /etc/httpd24/httpd.conf #將此指令添加到文件末尾即可
2.創建mod_jk.conf及workers.properties文件
# cat >>/etc/httpd24/extra/mod_jk.conf <<EOF LoadModule jk_module modules/mod_jk.so JkWorkersFile /etc/httpd24/extra/workers.properties JkLogFile logs/mod_jk.log JkLogLevel debug JkMount /* TomcatA JkMount /status/ stat1 EOF # cat >>/etc/httpd24/extra/workers.properties <<EOF worker.list=TomcatA,stat1 worker.TomcatA.port=8009 worker.TomcatA.host=172.16.10.61 worker.TomcatA.type=ajp13 worker.TomcatA.lbfactor=1 worker.stat1.type = status EOF
3.編輯httpd.conf修改ServerName並重啟httpd服務
#vi /etc/httpd24/httpd.conf
ServerName 172.16.10.72:80
# service httpd restart
4.修改tomcat服務器（172.16.10.61），添加測試頁面
# cd /usr/local/tomcat/conf/ # cp server.xml server.xml.bak # vi server.xml <Engine name="Catalina" defaultHost="172.16.10.72">
<Host name="172.16.10.72" appBase="/web/eivll0m" unpackWARs="true" autoDeploy="true">
<Valve className="org.apache.catalina.valves.AccessLogValve" directory="logs" prefix="eivll0m_access_log." suffix=".txt" pattern="%h %l %u %t "%r" %s %b" />
<Context path="" docBase="/web/eivll0m" />
</Host>
創建網站存放目錄並創建測試頁
# mkdir -p /web/eivll0m # vi /web/eivll0m/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>
重啟tomcat服務並查看是否啟動成功
# catalina.sh stop # catalina.sh configtest # catalina.sh start # ss -antpl | grep java 0 1 ::ffff:127.0.0.1:8005 :::* users:(("java",1299,50)) 0 100 :::8009 :::* users:(("java",1299,43)) 0 100 :::8080 :::* users:(("java",1299,42))
5.訪問Apache主機(172.16.10.72)，驗證是否代理成功
6.修改Apache配置文件(mod_jk.conf、workers.properties)，實現負載均衡
# cat >>/etc/httpd24/extra/mod_jk.conf <<EOF LoadModule jk_module modules/mod_jk.so JkWorkersFile /etc/httpd24/extra/workers.properties JkLogFile logs/mod_jk.log JkLogLevel debug JkMount /* lbcluster JkMount /status/ stat1 EOF
# cat >>/etc/httpd/extra/workers.properties <<EOF worker.list=lbcluster,stat1 worker.TomcatA.port=8009 worker.TomcatA.host=172.16.10.61 worker.TomcatA.type=ajp13 worker.TomcatA.lbfactor=1 worker.TomcatB.port = 8009 worker.TomcatB.host=172.16.10.62 worker.TomcatB.type = ajp13 worker.TomcatB.lbfactor = 1 worker.lbcluster.type = lb worker.lbcluster.sticky_session = 0 #取值為{1|0}1將用戶session與后端服務器綁定，0為不綁定，如果支持session復制或session共享可以設置為0 worker.lbcluster.balance_workers = TomcatA, TomcatB worker.stat1.type = status EOF
7.修改tomcat服務器（172.16.10.62），添加測試頁面
# cd /usr/local/tomcat/conf/ # cp server.xml server.xml.bak # vi server.xml <Engine name="Catalina" defaultHost="172.16.10.72">
<Host name="172.16.10.72" appBase="/web/eivll0m" unpackWARs="true" autoDeploy="true">
<Valve className="org.apache.catalina.valves.AccessLogValve" directory="logs" prefix="eivll0m_access_log." suffix=".txt" pattern="%h %l %u %t "%r" %s %b" />
<Context path="" docBase="/web/eivll0m" />
</Host>
創建網站存放目錄並創建測試頁
# mkdir -p /web/eivll0m # vi /web/eivll0m/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>
重啟tomcat服務並查看是否啟動成功
# catalina.sh stop # catalina.sh configtest # catalina.sh start # ss -antpl | grep java 0 1 ::ffff:127.0.0.1:8005 :::* users:(("java",1303,50)) 0 100 :::8009 :::* users:(("java",1303,43)) 0 100 :::8080 :::* users:(("java",1303,42))
8.訪問Apache服務器（172.16.10.72），測試是否實現負載均衡（如下表示測試成功）
五.安裝並配置Keepalived實現高可用
1.在apache服務器（172.16.10.72、172.16.10.75）安裝keepalived
yum -y install keepalived
2.配置Keepalived(172.16.10.72)
# vi /etc/keepalived/keepalived.conf ! Configuration File for keepalived global_defs { notification_email { acassen@firewall.loc failover@firewall.loc sysadmin@firewall.loc } notification_email_from admin@eivll0m.com smtp_server 172.16.10.0 smtp_connect_timeout 30 router_id LVS_DEVEL } vrrp_script chk_httpd { script "killall -0 httpd" interval 1 weight -2 } vrrp_instance httpd_1 { state MASTER interface eth0 virtual_router_id 58 priority 100 #定義優先級 advert_int 1 authentication { auth_type PASS auth_pass 1058 } virtual_ipaddress { 172.16.10.77 #vip } track_script { chk_httpd } }
# service keepalived start #啟動keepalived服務
# chkconfig keepalived on
3.配置Keepalived(172.16.10.75)
# vi /etc/keepalived/keepalived.conf ! Configuration File for keepalived global_defs { notification_email { acassen@firewall.loc failover@firewall.loc sysadmin@firewall.loc } notification_email_from admin@eivll0m.com smtp_server 172.17.10.0 smtp_connect_timeout 30 router_id LVS_DEVEL } vrrp_script chk_httpd { script "killall -0 httpd" interval 1 weight -2 } vrrp_instance httpd_1 { state BACKUP interface eth0 virtual_router_id 58 priority 99 #定義優先級 advert_int 1 authentication { auth_type PASS auth_pass 1058 } virtual_ipaddress { 172.16.10.77 #vip } track_script { chk_httpd } }
# service keepalived start
# chkconfig keepalived on
4.編輯httpd.conf(172.16.10.72)，並拷貝至172.16.10.75
# vi /etc/httpd24/httpd.conf ServerName www.eivll0m.com:80 # service httpd restart # cd /etc/httpd24/ # scp httpd.conf 172.16.10.75:/etc/httpd24/ # cd extra/ # scp mod_jk.conf workers.properties 172.16.10.75:/etc/httpd24/extra/
# service httpd restart #兩台apache服務器分別執行
5.編輯tomcat服務器(172.17.10.61和172.16.10.62)的server.xml
# vi server.xml <Engine name="Catalina" defaultHost="www.eivll0m.com">
<Host name="www.eivll0m.com" appBase="/web/eivll0m" unpackWARs="true" autoDeploy="true">
<Valve className="org.apache.catalina.valves.AccessLogValve" directory="logs" prefix="eivll0m_access_log." suffix=".txt" pattern="%h %l %u %t "%r" %s %b" />
<Context path="" docBase="/web/eivll0m" />
</Host>
# catalina.sh stop
# catalina.sh start
5.通過www.eivll0m.com(172.16.10.77)進行訪問測試
注意：測試時關閉所有服務器iptables，如果沒有做DNS解析，可在測試機上修改hosts文件來實現。
6.模擬一台apache故障，驗證keepalived是否可以成功轉移服務
# ip addr show eth0 #172.16.10.72上執行 2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000 link/ether 00:0c:29:e9:b8:52 brd ff:ff:ff:ff:ff:ff inet 172.16.10.72/24 brd 172.16.10.255 scope global eth0 inet 172.16.10.77/32 scope global eth0 inet6 fe80::20c:29ff:fee9:b852/64 scope link tentative dadfailed valid_lft forever preferred_lft forever # ip addr show eth0 #172.16.10.75上執行 2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000 link/ether 00:0c:29:c8:1a:08 brd ff:ff:ff:ff:ff:ff inet 172.16.10.75/24 brd 172.16.10.255 scope global eth0 inet 192.168.200.16/32 scope global eth0 inet 192.168.200.17/32 scope global eth0 inet 192.168.200.18/32 scope global eth0 inet6 fe80::20c:29ff:fec8:1a08/64 scope link tentative dadfailed valid_lft forever preferred_lft forever # service httpd stop #停止172.16.10.72上的httpd服務 # ip addr show eth0 #172.16.10.72上執行 2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000 link/ether 00:0c:29:e9:b8:52 brd ff:ff:ff:ff:ff:ff inet 172.16.10.72/24 brd 172.16.10.255 scope global eth0 inet6 fe80::20c:29ff:fee9:b852/64 scope link tentative dadfailed valid_lft forever preferred_lft forever # ip addr show eth0 #172.16.10.75上執行 2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000 link/ether 00:0c:29:c8:1a:08 brd ff:ff:ff:ff:ff:ff inet 172.16.10.75/24 brd 172.16.10.255 scope global eth0 inet 192.168.200.16/32 scope global eth0 inet 192.168.200.17/32 scope global eth0 inet 192.168.200.18/32 scope global eth0 inet 172.16.10.77/32 scope global eth0 #vip已經成功轉移過來 inet6 fe80::20c:29ff:fec8:1a08/64 scope link tentative dadfailed valid_lft forever preferred_lft forever
通過上面的步驟我們可以看到，在172.16.10.72上停止apache服務，keepalived會檢測到，另一台keepalived服務器會接管vip，web服務不會中斷，從而實現了高可用性。
7.配置tomcat實現session共享
7.1.配置172.16.10.61這台tomcat服務器
# vi /usr/local/tomcat/conf/server.xml #在<Engine>標簽內（對所有主機生效）添加或修改如下內容，另外也可以添加在<Host>標簽內，對當前主機生效。並去掉此段前后注釋 <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="224.0.0.1" #組播地址 port="45564" frequency="500" dropTime="3000"/> <Receiver className="org.apache.catalina.tribes.transport.nio.NioReceiver" address="172.16.10.61" 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"/> </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>
# mkdir /web/eivll0m/WEB-INF # cp /usr/local/tomcat/conf/web.xml /web/eivll0m/WEB-INF/ # vim /web/eivll0m/WEB-INF/web.xml <web-app xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" version="3.0"> <distributable/> #添加此行內容
# catalina.sh stop # catalina.sh start # ss -tanlp | grep java 0 1 ::ffff:127.0.0.1:8005 :::* users:(("java",1935,55)) 0 100 :::8009 :::* users:(("java",1935,43)) 0 100 :::8080 :::* users:(("java",1935,42)) 0 50 ::ffff:172.16.10.61:4000 :::* users:(("java",1935,44))
7.2.配置172.16.10.62這台tomcat服務器
# scp /usr/local/tomcat/conf/server.xml 172.16.10.62:/usr/local/tomcat/conf/
# scp -r /web/eivll0m/WEB-INF 172.16.10.62:/web/eivll0m/
# vi /usr/local/tomcat/conf/server.xml address="172.16.10.62" #更改IP port="4000" autoBind="100" selectorTimeout="5000" maxThreads="6"/> # catalina.sh stop # catalina.sh start # ss -antpl|grep java 0 1 ::ffff:127.0.0.1:8005 :::* users:(("java",2041,61)) 0 100 :::8009 :::* users:(("java",2041,43)) 0 100 :::8080 :::* users:(("java",2041,42)) 0 50 ::ffff:172.16.10.62:4000 :::* users:(("java",2041,44))
注：因為tomcat的session同步功能需要用到組播，windows默認情況下是開通組播服務的，但是linux默認情況下並沒有開通，可以通過指令打開route add -net 224.0.0.0 netmask 240.0.0.0 dev eth0，如果需要服務器啟動時即開通組播需在/etc/sysconfig/static-routes文件內加入eht0 net 224.0.0.0 netmask 240.0.0.0。
7.3.驗證session共享是否實現
通過以上截圖可以看出session共享已經實現。