In this document, $TOMCAT_HOME is used to refer to the absolute path of the directory containing the working Tomcat server, and $WORK_DIR is used to refer to the directory you prefer to work in.
Steps to upgrade Tomcat
1. Unzip the new downloaded Tomcat9.zip archive into the $WORK_DIR
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$ cd WORK_DIR
$ unzip Tomcat9x.zip
2. Change directory to new Tomcat conf.
$ cd tomcat-as/conf
3. Edit the new context.xml file and configure the database connection pool by referring to the working context.xml and save the file.
$ vi context.xml
4. Edit the new server.xml file and configure the Tomcat ports by referring to the working server.xml file and save the file.
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8. configure the Tomcat to run as a service.
Please refer to this Wiki page.
Note:
Before following the above steps, please make sure Tomcat is not in a running state.
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