From the documentation, I believe that the Task Server should start after I set up the JAVA_HOME, but it has been failing to start, with only a message "Failed to restart task server."
I am running an instance of Splunk version 8.1.5. When installing DBx 3.17.2, I installed OpenJDK 8, DBx started that it required Java 11. So I installed java-11-openjdk version 11.0.23.0.9.