Problem scenario
You are running SonarQube. The service seems to start (based on the output of "sudo systemctl status sonar"). But based on an nmap command on your server's external IP address, you see no service is listening. You go to the logs directory and cannot find the ce.log file. You cannot reach the web UI for SonarQube. How do you fix this problem?
Possible Solution #1
Look at your sonar.properties file. Is the "sonar.web.host" stanza correct? Is there a typo in the hostname? Is the hostname configured in your DNS server or /etc/hosts file? A typo in this stanza, e.g., sonar.web.host=wrongservername, could cause the problem you experienced.
Possible Solution #2
An underpowered server may take time to rebuild indices. You may need to wait a few minutes. If you want to add RAM or CPU to your server, see this link if you are using AWS, or see this link if you are using GCP.