You should start Tomcat as a batch job instead of manually starting it from QSH. Schedule it to start automatically when your IBM i starts up.
Use the following command (adjust the parameters as required):
SBMJOB CMD(QSH CMD('/home/tony/java-interop-tutorial/tomcat/bin/startup.sh'))
JOB(CATALINA) JOBQ(QBATCH)
CPYENVVAR(*YES) ALWMLTTHD(*YES)
Check the log file to see if it starts up successfully.
Run Qshell. Use the cat command to dump the content of <tomcat-root>/logs/catalina.out.
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