上篇文章,已经明确了tomcat集群的必要性,主要从高可用和高并发量考虑。一般使用tomcat集群搭建,都要使用前置设一个nginx或apache作个反向代理,将请求转发给后端tomcat。使用tomcat集群,必然会引来session数据共享问题。如何解决这个问题?可借助memcached实现。本章主要搭建一个tomcat双节点集群,算“准备”篇吧。
主要内容
测试单台tomcat的吞吐率
搭建apache+mod_jk+2个tomcat集群环境
环境准备
确认apache服务位置及版本号
[root@hadoop1 httpd]# httpd -vServer version: Apache/2.2.15 (Unix)Server built: Feb 22 2013 11:17:44[root@hadoop1 httpd]# which httpd/usr/sbin/httpd#apache主目录:/etc/httpd
确认JDK 及tomcat服务
[hadoop@hadoop1 tomcat-sets]$ ls /u01/tomcat-setsapache-tomcat-node1[hadoop@hadoop1 apache-tomcat-node1]$ cat /proc/meminfo MemTotal: 1937148 kB...[hadoop@hadoop1 /]$ /u01/tomcat-sets/apache-tomcat-node1/bin/version.sh Using CATALINA_BASE: /u01/tomcat-sets/apache-tomcat-node1Using CATALINA_HOME: /u01/tomcat-sets/apache-tomcat-node1Using CATALINA_TMPDIR: /u01/tomcat-sets/apache-tomcat-node1/tempUsing JRE_HOME: /usr/local/java/jdk1.6.0_45...Server version: Apache Tomcat/7.0.33Server built: Nov 18 2012 04:15:21Server number: 7.0.33.0OS Name: LinuxOS Version: 2.6.32-358.el6.i686Architecture: i386JVM Version: 1.6.0_45-b06JVM Vendor: Sun Microsystems Inc.
1.测试单台tomcat的吞吐率
1.1准备一个静态测试资源(staticProtocal.html,大小50K)
资源可以通过http://192.168.163.146:8080/examples/staticProtocal.html访问
[hadoop@hadoop1 examples]$ ll /u01/tomcat-sets/apache-tomcat-node1/webapps/examplestotal 72-rw-r--r--. 1 hadoop hadoop 1179 Nov 19 2012 index.htmldrwxr-xr-x. 22 hadoop hadoop 4096 Aug 10 18:48 jspdrwxr-xr-x. 3 hadoop hadoop 4096 Aug 10 18:48 servlets-rw-rw-r--. 1 hadoop hadoop 50663 Aug 12 21:09 staticProtocal.htmldrwxr-xr-x. 7 hadoop hadoop 4096 Aug 10 18:48 WEB-INFdrwxr-xr-x. 2 hadoop hadoop 4096 Aug 10 18:48 websocket
1.2启动apache-tomcat-node1,端口为默认的8080
1.3 在另外一台主机使用apache ab命令测试
C:\Apache24\bin>ab -n 10000 -c 4 http://192.168.163.146:8080/examples/staticProtocal.htmlThis is ApacheBench, Version 2.3 <$Revision: 1604373 $>Copyright 1996 Adam Twiss, Zeus Technology Ltd, http://www.zeustech.net/Licensed to The Apache Software Foundation, http://www.apache.org/Benchmarking 192.168.163.146 (be patient)Completed 1000 requests...Completed 10000 requestsFinished 10000 requestsServer Software: Apache-Coyote/1.1Server Hostname: 192.168.163.146Server Port: 8080Document Path: /examples/staticProtocal.htmlDocument Length: 50663 bytesConcurrency Level: 4Time taken for tests: 12.065 secondsComplete requests: 10000Failed requests: 0Total transferred: 509120000 bytesHTML transferred: 506630000 bytesRequests per second: 828.81 [#/sec] (mean)Time per request: 4.826 [ms] (mean)Time per request: 1.207 [ms] (mean, across all concurrent requests)Transfer rate: 41207.63 [Kbytes/sec] received...
经过测试,单台tomcat的结果是:QPS:828.81
都有这样一个共识,apache处理静态文件的能力,比tomcat强大。是骡子是马,比比看。
1.4 简单编辑apache配置文件httpd.conf。(最好修改之前备份下)
$ cat /etc/httpd/conf/httpd.conf ...ServerName localhost:80DocumentRoot "/var/www/html"...
1.5 将刚才的staticProtocal.html文件,复制到DocumentRoot“/var/www/html”目录下。
$ ls /var/www/html/staticProtocal.html
1.6 启动httpd
$ service httpd startStarting httpd: [ OK ]
这时候可以通过链接访问资源:
1.7 测试apache吞吐量
C:\Apache24\bin>ab -n 10000 -c 4 http://192.168.163.146/staticProtocal.htmlThis is ApacheBench, Version 2.3 <$Revision: 1604373 $>Copyright 1996 Adam Twiss, Zeus Technology Ltd, http://www.zeustech.net/Licensed to The Apache Software Foundation, http://www.apache.org/Benchmarking 192.168.163.146 (be patient)Completed 1000 requests...Finished 10000 requestsServer Software: Apache/2.2.15Server Hostname: 192.168.163.146Server Port: 80Document Path: /staticProtocal.htmlDocument Length: 50663 bytesConcurrency Level: 4Time taken for tests: 11.902 secondsComplete requests: 10000Failed requests: 0Total transferred: 509350000 bytesHTML transferred: 506630000 bytesRequests per second: 840.17 [#/sec] (mean)Time per request: 4.761 [ms] (mean)Time per request: 1.190 [ms] (mean, across all concurrent requests)Transfer rate: 41790.94 [Kbytes/sec] received
经过测试,单台apache的结果是:QPS:840.17
显而易见,apache处理静态文件能力略高于tomcat.
接下来,那就利用apache搭建一个双节点tomcat集群,顺带验证下QPS能达到多少。这是下一小节内容。
2.搭建apache+mod_jk+2个tomcat集群环境
2.1下载mod_jk并安装
要安装httpd-devel,否则会configure: error: Cannot find the WebServer
# yum install httpd-devel## 安装完httpd-devel之后,新添加目录/usr/sbin/apxs##下载# wget ##解压 # tar zxvf tomcat-connectors-1.2.41-src.tar.gz # cd tomcat-connectors-1.2.41-src/native # ./buildconf.sh --with-apxs=/usr/sbin/apxs # make
到这里mod_jk.so已经生成了,最后将mod_jk.so放到apache的modules 目录下
cp /u01/software/tomcat-connectors-1.2.41-src/native/apache-2.0/mod_jk.so /etc/httpd/modules
2.2配置mod_jk
请参考:
mod_jk:支持平台Linux, FreeBSD, AIX, HP-UX, MacOS X, Solaris,Apache 1.3 and/or 2.x
mod_jk: 支持Tomcat 3.2 to Tomcat 8.
redirector 使用协议:ajp12 and ajp13
ajp12 协议针对Tomcat 3.2.x and 3.3.x.
ajp13协议支持tomcat 4+
mod_jk:2个组成部分。
The Apache HTTP Server module。由平台决定,一般是mod_jk.so, mod_jk.nlm or MOD_JK.SRVPGM
workers.properties :描述Tomcat 相关的host(s) and port(s)文件。
2.3启用jk_module模块
将下面内容片段,加入/etc/httpd/httpd.conf
# Load mod_jk moduleLoadModule jk_module modules/mod_jk.soJkWorkersFile conf/workers.propertiesJkLogFile logs/mod_jk.logJkLogLevel infoinclude "conf/mod_jk.conf"
2.4 配置后端tomcat 主机及端口映射,编辑或新建文件,/etc/httpd/workers.properties
配置说明参照:https://tomcat.apache.org/connectors-doc/reference/workers.html
worker.list=tomcat1worker.tomcat1.port=8009worker.tomcat1.host=127.0.0.1worker.tomcat1.type=ajp13#worker.tomcat1.lbfactor=1
现在达到的效果是apache反代1个tomcat。所以不需要配置额外的负载均衡等信息。
2.5 编辑conf/mod_jk.conf,增加资源映射
#LoadModule jk_module modules/mod_jk.soJkMount /*.jsp tomcat1JkMount /examples/* tomcat1#JkWorkersFile conf/workers.properties
注释的两行,由于已经在httpd.conf中已经配置,所以不需要重复配置。
2.6 启动tomcat,及apache
笔者,在这一步经过测试,不能正常达到代理效果。
通过查看日志信息(/var/log/httpd/mod_jk.log)
[Fri Aug 12 22:49:23.051 2016] [9739:3078039376] [error] init_jk::mod_jk.c (3574): Initializing shm:/etc/httpd/logs/jk-runtime-status.9739 errno=13. Load balancing workers will not function properly.
通过参照网上解决方案:临时将selinux关闭
确认selinux状态 /usr/sbin/sestatus -v 临时关闭 setenforce 0 永久关闭 修改/etc/selinux/config 设置为 SELINUX=disabled
访问测试,没有问题
到了这里,完成了apache+单台tomcat的配置。
C:\Apache24\bin>ab -n 10000 -c 4 http://192.168.163.146/examples/staticProtocal.htmlThis is ApacheBench, Version 2.3 <$Revision: 1604373 $>Copyright 1996 Adam Twiss, Zeus Technology Ltd, http://www.zeustech.net/Licensed to The Apache Software Foundation, http://www.apache.org/Benchmarking 192.168.163.146 (be patient)Completed 1000 requests...Completed 10000 requestsFinished 10000 requestsServer Software: Apache/2.2.15Server Hostname: 192.168.163.146Server Port: 80Document Path: /examples/staticProtocal.htmlDocument Length: 50663 bytesConcurrency Level: 4Time taken for tests: 13.555 secondsComplete requests: 10000Failed requests: 0Total transferred: 509320000 bytesHTML transferred: 506630000 bytesRequests per second: 737.73 [#/sec] (mean)Time per request: 5.422 [ms] (mean)Time per request: 1.356 [ms] (mean, across all concurrent requests)Transfer rate: 36693.36 [Kbytes/sec] received
很遗憾,apache+单台tomcat组合的QPS:737.73
接下来,开始搭建apache+双节点环境。
3.搭建apache+mod_jk+2个tomcat集群环境
3.1复制tomcat环境为node2
[root@hadoop1 ~]# cd /u01/tomcat-sets/[root@hadoop1 tomcat-sets]# lsapache-tomcat-node1[root@hadoop1 tomcat-sets]# cp -R apache-tomcat-node1/ apache-tomcat-node2[root@hadoop1 bin]# chown -R hadoop:hadoop /u01/tomcat-sets [root@hadoop1 tomcat-sets]# lltotal 8drwxr-xr-x. 9 hadoop hadoop 4096 Aug 10 18:48 apache-tomcat-node1drwxr-xr-x 9 hadoop hadoop 4096 Aug 13 08:36 apache-tomcat-node2
3.2 修改apache-tomcat-node2节点的相关端口配置
<Server port="8005" shutdown="SHUTDOWN"> | <Server port="8006" shutdown="SHUTDOWN"> | |
<Connector port="8080" protocol="HTTP/1.1" connectionTimeout="20000" redirectPort="8443" /> | <Connector port="8081" protocol="HTTP/1.1" connectionTimeout="20000" redirectPort="8445" /> | |
<Connector port="8009" protocol="AJP/1.3" redirectPort="8445" /> | <Connector port="8019" protocol="AJP/1.3" redirectPort="8445" /> | |
配置好了简单测试下
访问以下均正常http://192.168.163.146:8080/examples/staticProtocal.html ps -ef |grep tomcat[root@hadoop1 apache-tomcat-node2]# ps -ef |grep tomcatroot 2797 1 0 08:31 pts/0 00:00:03 /usr/bin/java -Djava.util.logging.config.file=/u01/tomcat-sets/apache-tomcat-node1/conf/logging.properties -Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager -Djava.endorsed.dirs=/u01/tomcat-sets/apache-tomcat-node1/endorsed -classpath /u01/tomcat-sets/apache-tomcat-node1/bin/bootstrap.jar:/u01/tomcat-sets/apache-tomcat-node1/bin/tomcat-juli.jar -Dcatalina.base=/u01/tomcat-sets/apache-tomcat-node1 -Dcatalina.home=/u01/tomcat-sets/apache-tomcat-node1 -Djava.io.tmpdir=/u01/tomcat-sets/apache-tomcat-node1/temp org.apache.catalina.startup.Bootstrap startroot 2993 1 7 08:47 pts/0 00:00:00 /usr/bin/java -Djava.util.logging.config.file=/u01/tomcat-sets/apache-tomcat-node2/conf/logging.properties -Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager -Djava.endorsed.dirs=/u01/tomcat-sets/apache-tomcat-node2/endorsed -classpath /u01/tomcat-sets/apache-tomcat-node2/bin/bootstrap.jar:/u01/tomcat-sets/apache-tomcat-node2/bin/tomcat-juli.jar -Dcatalina.base=/u01/tomcat-sets/apache-tomcat-node2 -Dcatalina.home=/u01/tomcat-sets/apache-tomcat-node2 -Djava.io.tmpdir=/u01/tomcat-sets/apache-tomcat-node2/temp org.apache.catalina.startup.Bootstrap start
关闭一个tomcat节点,再测。(以前遇到过两个节点shutdown端口一样,导致关闭异常。)
3.3 配置后端tomcat 主机及端口映射,编辑或新建文件,/etc/httpd/workers.properties。
与2.4步骤一样,但要求要做到支持多节点和负载均衡。
worker.list=tomcat1worker.tomcat1.port=8009worker.tomcat1.host=127.0.0.1worker.tomcat1.type=ajp13worker.tomcat1.lbfactor=1worker.tomcat2.port=8019worker.tomcat2.host=127.0.0.1worker.tomcat2.type=ajp13worker.tomcat2.lbfactor=1worker.loadbalancer.type=lbworker.loadbalancer.balance_workers=tomcat1,tomcat2worker.loadbalancer.sticky_session=1
3.4 再次编辑节点服务器配置(server.xml)
node1节点server.xml最终信息
node2节点配置信息(server.xml)
值得一提的是:搭建过程中遇到一个问题。查看tomcat错误信息
java.net.BindException: Cannot assign requested address; No faulty members identified.
按照网上解决方案:主机配置错误。这才想起来,曾经切换过虚拟机的Network Adapter。
参照网址
解决方式,修改/etc/hosts中的IP,修改为现在的IP即可。[root@hadoop1 ~]# ifconfig
eth0 Link encap:Ethernet HWaddr 00:50:56:20:2B:84 inet addr:192.168.163.146 Bcast:192.168.163.255 Mask:255.255.255.0 inet6 addr: fe80::250:56ff:fe20:2b84/64 Scope:Link[root@hadoop1 ~]# cat /etc/hosts
192.168.163.146 hadoop13.5测试切换效果。
为了区分不同tomcat下的应用,将staticProtocal.html的内容作了下调整。
结果
为了排除浏览器缓存干扰,最好使用强制刷新。(CTRL+F5),这时候可以验证下权重。
3.6 测试下双节点集群的吞吐量。
C:\Apache24\bin>ab -n 10000 -c 4 http://192.168.163.146/examples/staticProtocal.html
This is ApacheBench, Version 2.3 <$Revision: 1604373 $>Copyright 1996 Adam Twiss, Zeus Technology Ltd, http://www.zeustech.net/Licensed to The Apache Software Foundation, http://www.apache.org/Benchmarking 192.168.163.146 (be patient)Completed 1000 requests...Finished 10000 requestsServer Software: Apache/2.2.15Server Hostname: 192.168.163.146Server Port: 80Document Path: /examples/staticProtocal.htmlDocument Length: 49598 bytesConcurrency Level: 4Time taken for tests: 13.996 secondsComplete requests: 10000Failed requests: 0Total transferred: 498670000 bytesHTML transferred: 495980000 bytesRequests per second: 714.51 [#/sec] (mean)Time per request: 5.598 [ms] (mean)Time per request: 1.400 [ms] (mean, across all concurrent requests)Transfer rate: 34795.47 [Kbytes/sec] receivedConnection Times (ms) min mean[+/-sd] median maxConnect: 0 0 0.4 1 5Processing: 0 5 9.1 3 162Waiting: 0 3 4.9 2 125Total: 0 6 9.1 3 162ERROR: The median and mean for the initial connection time are more than twice the standard deviation apart. These results are NOT reliable.吞吐量最差:714.51
为什么?
到了这里,还没有讲到session和memcached的影子。
结论(以1个50K的静态文本)
环境 | 吞吐量 |
1.单台tomcat | 828.81 |
2.单个apache | 840.17 |
3.apache+单tomcat节点 | 737.73 |
apache+双tomcat节点 | 714.51 |
通过对比,很直观得出结论。
apache处理静态文件的能力,比tomcat的能力高一些.
apache+单tomcat节点情况处理静态文件,纯属胡搞做实验,没有任何实际意义,很显然多了一层代理,当然吞吐量下来了。有点脱了裤子放屁的意思。
至于双节点tomcat的吞吐量下降的这么厉害,应该和我的环境有关系,我的CPU是单核,跑2个节点,想想发生了资源争用。
最后,这个实验不能掩盖tomcat的威力,它的强大在处理动态处理上,而这恰恰是apache做不了的。
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The End,下一篇,重点验证下集群间的session的共享,和memcached在集群中的应用。