Common problems and troubleshooting in installation

There are multiple issues which may arise during the installation of Tomcat 7. Let's discuss these issues:

Error: Permission denied for the Java binary

Scenario 1: The Java installation is not working, while executing the Java binary.

[root@localhost opt]# ./jdk-6u24-linux-i586.bin
-bash: ./jdk-6u24-linux-i586.bin: Permission denied

Issue: The Java binary doesn't have execute permissions with a specific user.

Fix: Change the permission to 0755 for ./jdk-6u24-linux-i586.bin using the following command:

chmod 0755 jdk-6u24-linux-i586.bin

Note

The chmod 0755 file is equivalent to u=rwx (4+2+1),go=rx (4+1 & 4+1). The 0 specifies no special modes.

Error: Tomcat is not able to find JAVA_HOME

Scenario 2: While starting the Tomcat startup script, the following error occurs:

[root@localhost bin]# ./startup.sh
Neither the JAVA_HOME nor the JRE_HOME environment variable is defined
At least one of these environment variables is needed to run this program

Fix: Check the .bash_profile and find out whether the following mentioned entry is present in the file:

JAVA_HOME=/opt/jdk1.6.0_24
PATH=$JAVA_HOME/bin:$PATH:$HOME/bin
export PATH JAVA_HOME

Error: Error in the logs showing port already in use

Scenario 3: Tomcat services is not displayed after running startup.sh.

Issue: This service is already running on the server.

Fix: Check for any Java process running in the system using the following command in Linux:

Ps -ef |grep tomcat

This command will show all Tomcat processes. If any process is running on an OS, kill it and run the startup scripts again.

In Windows, go to the Task Manager and check if any Java process is running for Tomcat. If any process is running, then kill the process and restart the Tomcat services.