nginx实现高性能负载均衡的Tomcat集群
1. 安装软件：
nginx
两个apache-tomcat
安装过程省略。
2.配置两个tomcat的http端口，第一个为18080，第二个为28080
注意：需要把server.xml文件中所有的端口都改为1xxxx或者2xxxx，不然就会有端口冲突，导致有一个tomcat启动不了。
如：
<?xml version='1.0' encoding='utf-8'?> <!-- Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements. See the NOTICE file distributed with this work for additional information regarding copyright ownership. The ASF licenses this file to You under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. --> <!-- Note: A "Server" is not itself a "Container", so you may not define subcomponents such as "Valves" at this level. Documentation at /docs/config/server.html --> <Server port="28005" shutdown="SHUTDOWN"> <Listener className="org.apache.catalina.startup.VersionLoggerListener" /> <!-- Security listener. Documentation at /docs/config/listeners.html <Listener className="org.apache.catalina.security.SecurityListener" /> --> <!--APR library loader. Documentation at /docs/apr.html --> <Listener className="org.apache.catalina.core.AprLifecycleListener" SSLEngine="on" /> <!-- Prevent memory leaks due to use of particular java/javax APIs--> <Listener className="org.apache.catalina.core.JreMemoryLeakPreventionListener" /> <Listener className="org.apache.catalina.mbeans.GlobalResourcesLifecycleListener" /> <Listener className="org.apache.catalina.core.ThreadLocalLeakPreventionListener" /> <!-- Global JNDI resources Documentation at /docs/jndi-resources-howto.html --> <GlobalNamingResources> <!-- Editable user database that can also be used by UserDatabaseRealm to authenticate users --> <Resource name="UserDatabase" auth="Container" type="org.apache.catalina.UserDatabase" description="User database that can be updated and saved" factory="org.apache.catalina.users.MemoryUserDatabaseFactory" pathname="conf/tomcat-users.xml" /> </GlobalNamingResources> <!-- A "Service" is a collection of one or more "Connectors" that share a single "Container" Note: A "Service" is not itself a "Container", so you may not define subcomponents such as "Valves" at this level. Documentation at /docs/config/service.html --> <Service name="Catalina"> <!--The connectors can use a shared executor, you can define one or more named thread pools--> <!-- <Executor name="tomcatThreadPool" namePrefix="catalina-exec-" maxThreads="150" minSpareThreads="4"/> --> <!-- A "Connector" represents an endpoint by which requests are received and responses are returned. Documentation at : Java HTTP Connector: /docs/config/http.html Java AJP Connector: /docs/config/ajp.html APR (HTTP/AJP) Connector: /docs/apr.html Define a non-SSL/TLS HTTP/1.1 Connector on port 8080 --> <Connector port="28888" protocol="HTTP/1.1" connectionTimeout="20000" redirectPort="28443" /> <!-- A "Connector" using the shared thread pool--> <!-- <Connector executor="tomcatThreadPool" port="8080" protocol="HTTP/1.1" connectionTimeout="20000" redirectPort="8443" /> --> <!-- Define a SSL/TLS HTTP/1.1 Connector on port 8443 This connector uses the NIO implementation with the JSSE engine. When using the JSSE engine, the JSSE configuration attributes must be used. --> <!-- <Connector port="8443" protocol="org.apache.coyote.http11.Http11NioProtocol" maxThreads="150" SSLEnabled="true"> <SSLHostConfig> <Certificate certificateKeystoreFile="conf/keystore-rsa.pem" type="RSA" /> </SSLHostConfig> </Connector> --> <!-- Define a SSL/TLS HTTP/1.1 Connector on port 8443 with HTTP/2 This connector uses the APR/native implementation. When using the APR/native implementation or the OpenSSL engine with NIO or NIO2 then the OpenSSL configuration attributes must be used. --> <!-- <Connector port="8443" protocol="org.apache.coyote.http11.Http11AprProtocol" maxThreads="150" SSLEnabled="true" > <UpgradeProtocol className="org.apache.coyote.http2.Http2Protocol" /> <SSLHostConfig honorCipherOrder="false" > <Certificate certificateKeyFile="conf/localhost-rsa-key.pem" certificateFile="conf/localhost-rsa-chain.pem" type="RSA" /> </SSLHostConfig> </Connector> --> <!-- Define an AJP 1.3 Connector on port 8009 --> <Connector port="28009" protocol="AJP/1.3" redirectPort="28443" /> <!-- An Engine represents the entry point (within Catalina) that processes every request. The Engine implementation for Tomcat stand alone analyzes the HTTP headers included with the request, and passes them on to the appropriate Host (virtual host). Documentation at /docs/config/engine.html --> <!-- You should set jvmRoute to support load-balancing via AJP ie : <Engine name="Catalina" defaultHost="localhost" jvmRoute="jvm1"> --> <Engine name="Catalina" defaultHost="localhost"> <!--For clustering, please take a look at documentation at: /docs/cluster-howto.html (simple how to) /docs/config/cluster.html (reference documentation) --> <!-- <Cluster className="org.apache.catalina.ha.tcp.SimpleTcpCluster"/> --> <!-- Use the LockOutRealm to prevent attempts to guess user passwords via a brute-force attack --> <Realm className="org.apache.catalina.realm.LockOutRealm"> <!-- This Realm uses the UserDatabase configured in the global JNDI resources under the key "UserDatabase". Any edits that are performed against this UserDatabase are immediately available for use by the Realm. --> <Realm className="org.apache.catalina.realm.UserDatabaseRealm" resourceName="UserDatabase"/> </Realm> <Host name="localhost" appBase="webapps" unpackWARs="true" autoDeploy="true"> <!-- SingleSignOn valve, share authentication between web applications Documentation at: /docs/config/valve.html --> <!-- <Valve className="org.apache.catalina.authenticator.SingleSignOn" /> --> <!-- Access log processes all example. Documentation at: /docs/config/valve.html Note: The pattern used is equivalent to using pattern="common" --> <Valve className="org.apache.catalina.valves.AccessLogValve" directory="logs" prefix="localhost_access_log" suffix=".txt" pattern="%h %l %u %t "%r" %s %b" /> </Host> </Engine> </Service> <Service name="Catalina"> <!--The connectors can use a shared executor, you can define one or more named thread pools--> <!-- <Executor name="tomcatThreadPool" namePrefix="catalina-exec-" maxThreads="150" minSpareThreads="4"/> --> <!-- A "Connector" represents an endpoint by which requests are received and responses are returned. Documentation at : Java HTTP Connector: /docs/config/http.html Java AJP Connector: /docs/config/ajp.html APR (HTTP/AJP) Connector: /docs/apr.html Define a non-SSL/TLS HTTP/1.1 Connector on port 8080 --> <Connector port="28080" protocol="HTTP/1.1" connectionTimeout="20000" redirectPort="28443" /> <!-- A "Connector" using the shared thread pool--> <!-- <Connector executor="tomcatThreadPool" port="8080" protocol="HTTP/1.1" connectionTimeout="20000" redirectPort="8443" /> --> <!-- Define a SSL/TLS HTTP/1.1 Connector on port 8443 This connector uses the NIO implementation with the JSSE engine. When using the JSSE engine, the JSSE configuration attributes must be used. --> <!-- <Connector port="8443" protocol="org.apache.coyote.http11.Http11NioProtocol" maxThreads="150" SSLEnabled="true"> <SSLHostConfig> <Certificate certificateKeystoreFile="conf/keystore-rsa.pem" type="RSA" /> </SSLHostConfig> </Connector> --> <!-- Define a SSL/TLS HTTP/1.1 Connector on port 8443 with HTTP/2 This connector uses the APR/native implementation. When using the APR/native implementation or the OpenSSL engine with NIO or NIO2 then the OpenSSL configuration attributes must be used. --> <!-- <Connector port="8443" protocol="org.apache.coyote.http11.Http11AprProtocol" maxThreads="150" SSLEnabled="true" > <UpgradeProtocol className="org.apache.coyote.http2.Http2Protocol" /> <SSLHostConfig honorCipherOrder="false" > <Certificate certificateKeyFile="conf/localhost-rsa-key.pem" certificateFile="conf/localhost-rsa-chain.pem" type="RSA" /> </SSLHostConfig> </Connector> --> <!-- Define an AJP 1.3 Connector on port 8009 --> <Connector port="28009" protocol="AJP/1.3" redirectPort="28443" /> <!-- An Engine represents the entry point (within Catalina) that processes every request. The Engine implementation for Tomcat stand alone analyzes the HTTP headers included with the request, and passes them on to the appropriate Host (virtual host). Documentation at /docs/config/engine.html --> <!-- You should set jvmRoute to support load-balancing via AJP ie : <Engine name="Catalina" defaultHost="localhost" jvmRoute="jvm1"> --> <Engine name="Catalina" defaultHost="localhost"> <!--For clustering, please take a look at documentation at: /docs/cluster-howto.html (simple how to) /docs/config/cluster.html (reference documentation) --> <!-- <Cluster className="org.apache.catalina.ha.tcp.SimpleTcpCluster"/> --> <!-- Use the LockOutRealm to prevent attempts to guess user passwords via a brute-force attack --> <Realm className="org.apache.catalina.realm.LockOutRealm"> <!-- This Realm uses the UserDatabase configured in the global JNDI resources under the key "UserDatabase". Any edits that are performed against this UserDatabase are immediately available for use by the Realm. --> <Realm className="org.apache.catalina.realm.UserDatabaseRealm" resourceName="UserDatabase"/> </Realm> <Host name="localhost" appBase="webapps" unpackWARs="true" autoDeploy="true"> <!-- SingleSignOn valve, share authentication between web applications Documentation at: /docs/config/valve.html --> <!-- <Valve className="org.apache.catalina.authenticator.SingleSignOn" /> --> <!-- Access log processes all example. Documentation at: /docs/config/valve.html Note: The pattern used is equivalent to using pattern="common" --> <Valve className="org.apache.catalina.valves.AccessLogValve" directory="logs" prefix="localhost_access_log" suffix=".txt" pattern="%h %l %u %t "%r" %s %b" /> </Host> </Engine> </Service> </Server>
3..写个简单的页面分别放到两个tomcat下，如图
18080下的test.html内容如下：
<html> <head> <meto http-equiv="Content-Type" content="text/html:charSet=GBK"> <title>一个简单的页面</title> </head> <body> the port is 18080 </body> </html>
28080下的test.html内容如下：
<html> <head> <meto http-equiv="Content-Type" content="text/html:charSet=GBK"> <title>一个简单的页面</title> </head> <body> hello this is 28080 ha ha ha .... </body> </html>
4.正常启动两个tomcat,测试是否正常启动：
访问http://localhost:18080/myhtml/test.html和http://localhost:28080/myhtml/test.html
如果能访问到对应的测试页面，测启动正常。
5.配置nginx，如下：
#user nobody;
worker_processes 1; #工作进程的个数，一般与计算机的cpu核数一致
#error_log logs/error.log;
#error_log logs/error.log notice;
#error_log logs/error.log info;
#pid logs/nginx.pid;
events {
worker_connections 1024; #单个进程最大连接数（最大连接数=连接数*进程数）
}
http {
include mime.types; #文件扩展名与文件类型映射表
default_type application/octet-stream; #默认文件类型
#log_format main '$remote_addr - $remote_user [$time_local] "$request" '
# '$status $body_bytes_sent "$http_referer" '
# '"$http_user_agent" "$http_x_forwarded_for"';
#access_log logs/access.log main;
sendfile on; #开启高效文件传输模式，sendfile指令指定nginx是否调用sendfile函数来输出文件，对于普通应用设为 on，如果用来进行下载等应用磁盘IO重负载应用，可设置为off，以平衡磁盘与网络I/O处理速度，降低系统的负载。注意：如果图片显示不正常把这个改成off。
#tcp_nopush on;
#keepalive_timeout 0;
keepalive_timeout 65; #长连接超时时间，单位是秒
gzip on; #启用Gizp压缩
#服务器的集群
upstream netitcast.com { #服务器集群名字
#服务器配置列表，weight是权重的意思，权重越大，分配的概率越大
server 127.0.0.1:18080 weight=1;
server 127.0.0.1:28080 weight=2;
}
#当前的Nginx的配置
server {
listen 8080; #监听80端口，可以改成其他端口
server_name localhost; #当前服务的域名，如果请求为localhost:8080,则交给http://netitcast.com的nginx集群来处理
#charset koi8-r;
#access_log logs/host.access.log main;
location / {
proxy_pass http://netitcast.com; #与 服务器集群名字 一致
proxy_redirect default;
}
#error_page 404 /404.html;
# redirect server error pages to the static page /50x.html
#
error_page 500 502 503 504 /50x.html;
location = /50x.html {
root html;
}
# proxy the PHP scripts to Apache listening on 127.0.0.1:80
#
#location ~ \.php$ {
# proxy_pass http://127.0.0.1;
#}
# pass the PHP scripts to FastCGI server listening on 127.0.0.1:9000
#
#location ~ \.php$ {
# root html;
# fastcgi_pass 127.0.0.1:9000;
# fastcgi_index index.php;
# fastcgi_param SCRIPT_FILENAME /scripts$fastcgi_script_name;
# include fastcgi_params;
#}
# deny access to .htaccess files, if Apache's document root
# concurs with nginx's one
#
#location ~ /\.ht {
# deny all;
#}
}
# another virtual host using mix of IP-, name-, and port-based configuration
#
#server {
# listen 8000;
# listen somename:8080;
# server_name somename alias another.alias;
# location / {
# root html;
# index index.html index.htm;
# }
#}
# HTTPS server
#
#server {
# listen 443 ssl;
# server_name localhost;
# ssl_certificate cert.pem;
# ssl_certificate_key cert.key;
# ssl_session_cache shared:SSL:1m;
# ssl_session_timeout 5m;
# ssl_ciphers HIGH:!aNULL:!MD5;
# ssl_prefer_server_ciphers on;
# location / {
# root html;
# index index.html index.htm;
# }
#}
include servers/*;
}
6.到此配置完成，下面开始演示负载均衡，
首先启动nginx，
localhost:nginx mhx$ sudo nginx
在浏览器中访问 http://localhost:8080，如果出现Nginx界面，则说明启动成功.
如：
7.测试负载均衡：
访问：http://localhost:8080/myhtml/test.html多次
页面出现内容：
the port is 18080 （出现频率占比1/3）
或者
hello this is 28080 ha ha ha .... （出现频率占比2/3）
