What are the steps for upgrading Tomcat?

The steps to upgrade Tomcat are as follows:

1. Back up the original Tomcat directory: Before upgrading, it is important to backup the original Tomcat directory in case there are any issues during the upgrade process and you need to revert back to the original state.

2. Download the latest version of Tomcat from the official Apache Tomcat website at https://tomcat.apache.org/.

Unzip the new version of Tomcat: Extract the downloaded Tomcat zip file into a new directory.

Backup the original Tomcat configuration files and copy them to a new directory: Backup the server.xml, web.xml, and other configuration files in the conf directory of the original Tomcat directory, and copy them to the conf directory of the new version of Tomcat.

5. Copy the deployment files from the original Tomcat to a new directory: Copy the application folders (such as ROOT, manager, etc.) from the webapps directory in the original Tomcat directory to the webapps directory of the new version Tomcat.

6. Copy the shared library files from the original Tomcat’s lib folder to a new directory: Copy the shared library files (such as mysql-connector-java.jar) from the lib folder in the original Tomcat directory to the lib folder in the new version of Tomcat.

7. Set up the environment variables for the new Tomcat: Depending on the operating system, configure the environment variables for the new version of Tomcat. For instance, in Windows, you can add the Tomcat’s bin directory to the system’s PATH environment variable.

Start a new Tomcat: Use the command line or startup script to launch the new version of Tomcat. During the startup process, it is recommended to check the log files to ensure there are no errors or exceptions.

Test the functionality of the new Tomcat: access the applications in the new version of Tomcat using a browser to ensure they are running properly.

Adjust the configuration as needed: Modify the configuration of the new version of Tomcat according to actual requirements. This may involve making changes to server.xml, web.xml, or other configuration files.

11. Remove the original Tomcat: Once the new version of Tomcat has been confirmed to run smoothly, you can delete or back up the original Tomcat directory to another location.

Before performing any upgrades, it is recommended to carefully read the official Tomcat documentation on upgrading and make sure to backup all important files and data.