在Debian系统上配置Tomcat集群涉及多个步骤,以下是一个详细的配置方案:
sudo apt update
sudo apt install default-jdk
/opt/tomcat。wget https://downloads.apache.org/tomcat/tomcat-9/v9.0.76/bin/apache-tomcat-9.0.76.tar.gz
tar -xvzf apache-tomcat-9.0.76.tar.gz -C /opt/tomcat
为了避免在生产系统的根用户下运行Tomcat,建议创建一个新的专用系统用户和组。
sudo groupadd tomcats
sudo useradd -s /bin/false -g tomcat -d /opt/tomcat tomcat
server.xml 文件:在每个Tomcat实例的 conf/server.xml 文件中,为 Engine 元素添加 jvmRoute 属性,用于标识不同的Tomcat实例。<Engine name="Catalina" defaultHost="localhost">
<Cluster className="org.apache.catalina.ha.tcp.SimpleTcpCluster">
<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="228.0.0.4" port="45564" frequency="500" dropTime="3000"/>
<Receiver className="org.apache.catalina.tribes.transport.nio.NioReceiver" address="auto" 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.TcpPingInterceptor"/>
<Interceptor className="org.apache.catalina.tribes.group.interceptors.TcpFailureDetector"/>
<Interceptor className="org.apache.catalina.tribes.group.interceptors.MessageDispatch15Interceptor"/>
</Channel>
<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.ClusterSessionListener"/>
</Cluster>
</Engine>
可以使用Nginx或Apache HTTP Server来实现负载均衡。以下是使用Nginx的示例配置:
upstream tomcat_cluster {
server 192.168.1.101:8080;
server 192.168.1.102:8080;
server 192.168.1.103:8080;
}
server {
listen 80;
server_name your_domain.com;
location / {
proxy_pass http://tomcat_cluster;
proxy_set_header Host $host;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_set_header X-Forwarded-Proto $scheme;
}
}
为每个Tomcat实例创建一个systemd服务文件,例如 tomcat1.service 和 tomcat2.service:
[Unit]
Description=Tomcat 9 servlet container
After=network.target
[Service]
Type=forking
User=tomcat
Group=tomcat
Environment="JAVA_HOME=/usr/lib/jvm/default-java"
Environment="CATALINA_PID=/opt/tomcat/latest/temp/tomcat1.pid"
Environment="CATALINA_HOME=/opt/tomcat/latest"
Environment="CATALINA_BASE=/opt/tomcat/latest"
Environment="CATALINA_OPTS=-Xms512M -Xmx1024M -server -XX:UseParallelGC"
ExecStart=/opt/tomcat/latest/bin/startup.sh
ExecStop=/opt/tomcat/latest/bin/shutdown.sh
RestartSec=10
Restart=always
[Install]
WantedBy=multi-user.target
启动和启用Tomcat服务:
sudo systemctl daemon-reload
sudo systemctl start tomcat1
sudo systemctl enable tomcat1
sudo systemctl start tomcat2
sudo systemctl enable tomcat2
通过模拟多用户访问来检查负载均衡和会话管理的工作情况。访问 http://your_domain.com,确认请求是否被正确分发到不同的Tomcat实例。
使用监控工具(如Prometheus和Grafana)持续监控各个Tomcat实例的性能指标,并根据需要进行调优,以确保集群的稳定性和高效性。