linux运维、架构之路-tomcat服务

一、tomcat介绍

      Tomcat服务器是一个免费的开放源代码的Web应用服务器，即能处理静态页面，又能处理动态的java页面

二、JDK安装

jdk是java开发工具包，也可以叫java虚拟机jvm，jvm会将一份代码自动转换成不同平台的代码，类似php功能

1、系统环境

[root@tomcat ~]# cat /etc/redhat-release 
CentOS Linux release 7.2.1511 (Core) 
[root@tomcat ~]# uname -r
3.10.0-327.el7.x86_64
[root@tomcat ~]# getenforce 
Disabled
[root@tomcat ~]# systemctl status firewalld.service
● firewalld.service - firewalld - dynamic firewall daemon
   Loaded: loaded (/usr/lib/systemd/system/firewalld.service; disabled; vendor preset: enabled)
   Active: inactive (dead)
[root@tomcat ~]# hostname -I
172.19.5.10 172.16.1.10

2、安装JDK

cd /application/tools/
#上传jdk-8u60-linux-x64.tar.gz
tar xf jdk-8u60-linux-x64.tar.gz -C /application/
ln -s /application/jdk1.8.0_60 /application/jdk
sed -i.ori '$a export JAVA_HOME=/application/jdk\nexport PATH=$JAVA_HOME/bin:$JAVA_HOME/jre/bin:$PATH\nexport CLASSPATH=.:$JAVA_HOME/lib:$JAVA_HOME/jre/lib:$JAVA_HOME/lib/tools.jar' /etc/profile
source /etc/profile

检查JDK版本信息

[root@tomcat ~]# java -version
java version "1.8.0_60"
Java(TM) SE Runtime Environment (build 1.8.0_60-b27)
Java HotSpot(TM) 64-Bit Server VM (build 25.60-b23, mixed mode)

三、部署tomcat

1、安装tomcat

cd /application/tools/
#上传apache-tomcat-8.0.27.tar.gz
tar xf apache-tomcat-8.0.27.tar.gz -C /application/
ln -s /application/apache-tomcat-8.0.27 /application/tomcat
echo 'export TOMCAT_HOME=/application/tomcat'>>/etc/profile
source /etc/profile
chown -R root.root /application/jdk/ /application/tomcat/

检查tomcat版信息

[root@tomcat ~]# /application/tomcat/bin/version.sh 
Using CATALINA_BASE:   /application/tomcat
Using CATALINA_HOME:   /application/tomcat
Using CATALINA_TMPDIR: /application/tomcat/temp
Using JRE_HOME:        /application/jdk
Using CLASSPATH:       /application/tomcat/bin/bootstrap.jar:/application/tomcat/bin/tomcat-juli.jar
Server version: Apache Tomcat/8.0.27
Server built:   Sep 28 2015 08:17:25 UTC
Server number:  8.0.27.0
OS Name:        Linux
OS Version:     3.10.0-327.el7.x86_64
Architecture:   amd64
JVM Version:    1.8.0_60-b27
JVM Vendor:     Oracle Corporation

2、tomcat目录介绍

[root@tomcat ~]# tree /application/tomcat -L 1
/application/tomcat
├── bin        #启动，关闭命令
├── conf       #配置文件 
├── lib
├── LICENSE
├── logs       #日志文件
├── NOTICE
├── RELEASE-NOTES
├── RUNNING.txt
├── temp
├── webapps    #站点目录
└── work

3、tomcat相关命令

/application/tomcat/bin/startup.sh #启动程序
/application/tomcat/bin/shutdown.sh #关闭程序
netstat -tunlp|grep java #查看tomcat端口信息
http://172.19.5.10:8080/
/logs/catalina.out #tomcat实时日志，此文件会越来越大，记得清空

4、配置tomcat管理

[root@tomcat ~]# tail -4 /application/tomcat/conf/tomcat-users.xml
  "manager-gui"/>
  "admin-gui"/>
  "tomcat" password="tomcat" roles="manager-gui,admin-gui"/>

/application/tomcat/bin/shutdown.sh
/application/tomcat/bin/startup.sh

http://172.19.5.10:8080/manager/status

注：适合测试环境，线上最好不用

 5、自定义站点目录

vim /application/tomcat/conf/server.xml #124行后加入以下内容
"" docBase="/application/tomcat/webapps/memtest" debug="0" reloadable="false" crossContext="true"/>
"37team" docBase="/application/tomcat/webapps/memtest" debug="0" reloadable="false" crossContext="true"/>

6、tomcat多实例

cd /application/tools/
tar xf apache-tomcat-8.0.27.tar.gz
cp -a apache-tomcat-8.0.27 tomcat8_1
cp -a apache-tomcat-8.0.27 tomcat8_2
sed -i 's#8005#8011#;s#8080#8081#' tomcat8_1/conf/server.xml 
sed -i 's#8005#8012#;s#8080#8082#' tomcat8_2/conf/server.xml
cp -a tomcat8_1 tomcat8_2 /application/
#tar zcf muti.tomcat.tar.gz ./tomcat8_1 ./tomcat8_2打包，以后用直接解压

7、nginx反向代理tomcat

#yum安装nginx
yum -y install nginx
/usr/share/nginx/html #yum安装nginx的站点目录
/etc/nginx/nginx.conf  #yum安装nginx的配置文件
vim /etc/nginx/nginx.conf #配置nginx负载均衡
    upstream web_pools {
        server 172.19.5.10:8081;
        server 172.19.5.10:8082;
        }
    server {
        listen       80;
        server_name  localhost;
        location / {
            index  index.jsp index.html index.htm;
            proxy_pass http://web_pools;
        }
     }

模拟数据

echo 8081 >/application/tomcat8_1/webapps/ROOT/index.jsp 
echo 8082 >/application/tomcat8_2/webapps/ROOT/index.jsp

测试负载均衡效果

8、jpress部署

yum -y install mariadb-server#数据库在7上面已改名
systemctl start mariadb.service
mysql#登录mysql
create database jpress DEFAULT CHARACTER SET utf8;
grant all on jpress.* to jpress@'localhost' identified by '123456';
#上传代码到站点目录
/application/tomcat8_1/webapps
mv jpress-web-newest jpress
mv jpress-web-newest.war /tmp/
http://172.19.5.10:8081/jpress/install
http://172.19.5.10:8081/jpress/admin/login

war包手动解压：

jar -xf memtest.war

9、tomcat监控

①直接获取tomcat的pid值

jps -lvm  #快速获取Java进程的pid，不用ps和grep

②windows监控tomcat工具

C:\Program Files\Java\jdk1.8.0_31\bin
jconsole.exe
jvisualvm.exe

③配置tomcat支持远监控功能

vim /application/tomcat/bin/catalina.sh
CATALINA_OPTS="$CATALINA_OPTS
-Dcom.sun.management.jmxremote 
-Dcom.sun.management.jmxremote.port=12345  
-Dcom.sun.management.jmxremote.authenticate=false 
-Dcom.sun.management.jmxremote.ssl=false 
-Djava.rmi.server.hostname=172.19.5.10"

netstat -lntup|grep 12345

遇到报错

错误: 代理抛出异常错误: java.net.MalformedURLException: Local host name unknown: java.net.UnknownHostException: tomcat: tomcat: unknown error

解决：主机名域名解析解决tomcat无法启动

④使用zabbix监控tomcat

yum install -y zabbix-java-gateway#前面已安装
#配置
/etc/init.d/zabbix-java-gateway start
sed -i -e '217a JavaGateway=127.0.0.1' -e '225a JavaGatewayPort=10052'  -e '235a StartJavaPollers=5' /etc/zabbix/zabbix_server.conf
/etc/init.d/zabbix-server restart

⑤zabbix网页添加监控tomcat

四、tomcat优化

1、安全优化

①关闭管理端口保护

 #修改默认的8005端口，"SHUTDOWN"字符串也要改

②注释ajp连接端口保护

 #注释此行

③禁用管理端

#webapps下面只保留一个ROOT空目录，其余的都清除

 ④tomcat降权启动

#降权，降低权限，像nginx，tomcat等都支持以普通用户的方式启动

useradd tomcat
cp -a /application/tools/tomcat8_1 /home/tomcat/
chown -R tomcat.tomcat /home/tomcat/tomcat8_1/
su -c '/home/tomcat/tomcat8_1/bin/startup.sh' tomcat

⑤生产环境关闭自动部署功能

       #true改为false　　

2、tomcat性能优化

       Tomcat是最消耗内存的，如果有无限大的内存，tomcat就跑的特别快，优化方法如下：

①加大内存
②减少内存的消耗量：开发写得代码只是不停消耗内存，但是从来不释放
    垃圾回收机制：定期扫描内存使用情况，找到未被使用的内存，回收周期性，一定内存使用量，每次垃圾回收都会使业务停止文档，jvm优化主要从垃圾回收策略开始阐述
③定期重启Tomcat

3、修改tomcat使用内存，tomcat默认消耗系统内存的1/4

 vim /home/tomcat/tomcat8_1/bin/catalina.sh #97行
 JAVA_OPTS="-Djava.awt.headless=true -Dfile.encoding=UTF-8 -server -Xms3072m -Xmx3072m -XX:NewSize=1536m -XX:MaxNewSize=1536m -XX:PermSize=1536m -XX:MaxPermSize=1536m"

访问测试

http://172.19.5.10:8081/meminfo.jsp

4、Tomcat获取用户IP地址

①tomcat配置文件/conf/server.xml下配置

"org.apache.catalina.valves.AccessLogValve" directory="logs"
    prefix="localhost_access_log" suffix=".txt"
    pattern="%h %l %u %t %r %s %b" />

②前面有负载均衡的时候，获取真实IP可以使用下面的配置

"org.apache.catalina.valves.AccessLogValve" directory="logs"
    prefix="localhost_access_log." suffix=".txt"
    pattern="%{X-Forwarded-For}i %h %l %u %t %r %s %b" />

五、tomcat启动脚本开发

[root@tomcat scripts]# cat tomcat.sh
#!/bin/sh

Tomcat_Path=/application/tomcat/

usage() {
    echo "usage: $0 [start|stop|status|restart]"
}

status_tomcat() {
ps aux|grep java|grep tomcat|grep -v grep
}

start_tomcat() {
/application/tomcat/bin/startup.sh
   echo "tomcat is starting"
}

stop_tomcat() {

TomcatPid=$(ps aux|grep java|grep tomcat|grep -v grep|awk '{print $2}')
kill -9 $TomcatPid
sleep 5

TSTAT=$(ps aux|grep java|grep tomcat|grep -v grep|awk '{print $2}')
    if [ -z $TSTAT ];then
	echo "tomcat is stopped" 
    else
  	kill -9 $TSTAT
    fi
cd ${Tomcat_Path}
rm -fr temp/*
rm -fr work/*
}
main() {
case $1 in
    start)
         start_tomcat;;
    stop)
         stop_tomcat;;
    status)
         status_tomcat;;
    restart)
         stop_tomcat && start_tomcat;;
    *)
         usage;
esac
}
main $1

六、tomcat在CentOS7系统上启动慢

1、tomcat启动慢原因现象

       在CentOS7启动Tomcat时，启动过程很慢，需要几分钟，经过查看日志，发现耗时在这里：是session引起的随机数问题导致的

2、解决办法

①方法

vim $JAVA_HOME/jre/lib/security/java.security
securerandom.source=file:/dev/random
#改为
securerandom.source=file:/dev/urandom

②方法

vim $TOMCAT_HOME/bin/catalina.sh
if [[ "$JAVA_OPTS" != *-Djava.security.egd=* ]]; then
    JAVA_OPTS="$JAVA_OPTS -Djava.security.egd=file:/dev/urandom"
fi

③方法

yum install rng-tools -y
systemctl start rngd.service
systemctl enable rngd.service

七、Jar包介绍

很多时候开发会给我们一个jar包，让我们运行，启动命令如下：

nohup java -jar jar包名称.jar > user.out &

转载于:https://www.cnblogs.com/yanxinjiang/p/7866716.html