Stop tomcat in docker container

[Daniel-S-Python]

Hello, I'm new to tomcat and I don't know where I can find this info. Maybe somebody here can help:
How can I stop the tomcat service inside the docker container when I have an interactive shell opend? I must stop the service to update a webapp.

Thank you for any help.

BR

Daniel

[wglambert]

The usual method for containers is that they don't have a process supervisor like init or systemd which would otherwise take the place of PID 1.

$ docker exec -it tomcat bash
root@ef341a450431:/usr/local/tomcat# ps aux
USER       PID %CPU %MEM    VSZ   RSS TTY      STAT START   TIME COMMAND
root         1 29.3  4.0 2585620 82600 ?       Ssl  19:41   0:02 /usr/local/openjdk-11/bin/java -Djava.util.logging.config.file=/usr/local/tomcat/conf/l
root        40  1.0  0.1   5752  3612 pts/0    Ss   19:41   0:00 bash
root        46  0.0  0.1   9392  3100 pts/0    R+   19:41   0:00 ps aux

Because tomcat is PID 1 it can't be restarted since that requires the process to exit, and PID 1 is special in that regard that when it exits so does the container.

[tianon]

(In the future, these sorts of questions/requests would be more appropriately posted to a dedicated support forum, such as the Docker Community Forums, the Docker Community Slack, or Stack Overflow. 👍)