Step-by-Step Guide to Installing Java and Tomcat, Configuring Multiple Instances on Linux

First, install the Java runtime environment: yum install java-1.8.0 -y Verify the installation with java -version, which should display something like:

openjdk version "1.8.0_222" OpenJDK Runtime Environment (build 1.8.0_222-b10) OpenJDK 64-Bit Server VM (build 25.222-b10, mixed mode)

Set the TOMCAT_HOME environment variable for all users: echo 'export TOMCAT_HOME=/opt/tomcat' >> /etc/profile Next, install Tomcat:

Check the Java version again (optional) and list the /opt directory to confirm the Tomcat archive is present: ls /opt → apache-tomcat-8.5.43.tar.gz Extract the archive and create a symbolic link named tomcat:

tar -zxvf apache-tomcat-8.5.43.tar.gz -C /opt/

ln -s apache-tomcat-8.5.43 tomcat

The webapps directory now contains the default applications (docs, examples, host‑manager, manager, ROOT).

In the bin directory, the key scripts are: startup.sh – starts Tomcat shutdown.sh – stops Tomcat catalina.sh – core management script for JVM options and Tomcat parameters

Start Tomcat with: ./startup.sh The console will show the CATALINA paths and confirm that Tomcat has started. Verify the Java process: ps -ef | grep java Log files are located in /opt/tomcat/logs (e.g., catalina.out, catalina.YYYY-MM-DD.log, localhost_access_log.YYYY-MM-DD.txt).

To stop Tomcat, run: ./bin/shutdown.sh After shutdown, check that no Java processes remain and optionally use netstat -nltp to confirm ports are free.

For security, move all files out of the webapps directory except the ROOT folder:

mv docs examples host-manager manager /tmp/

mv ROOT/* /tmp/

Deploy your website by placing its content directly into the ROOT directory.

To run multiple Tomcat instances, copy the original installation directory and adjust each instance’s conf/server.xml ports with sed:

cp -a apache-tomcat-8.5.43 tomcat_01

cp -a apache-tomcat-8.5.43 tomcat_02

Example port changes for the first instance:

sed -i 's#8005#8006#g' tomcat_01/conf/server.xml

sed -i 's#8009#8010#g' tomcat_01/conf/server.xml

sed -i 's#8080#8081#g' tomcat_01/conf/server.xml

And for the second instance:

sed -i 's#8005#8007#g' tomcat_02/conf/server.xml

sed -i 's#8009#8011#g' tomcat_02/conf/server.xml

sed -i 's#8080#8082#g' tomcat_02/conf/server.xml

Start each instance with its own startup.sh and configure a reverse‑proxy (e.g., Nginx) to route traffic to the different ports.