Without more information, it's hard to provide a thorough answer to your question. One place to look to start debugging an issue is Jira's log file. It is usually found at:
For full instructions on installing Jira on a Linux server, see the documentation from Atlassian.
One common issue with Tomcat, the web server used by Jira, is that its default entropy source is blocking and will cause extremely long startup times in some environments such as cloud servers. In your
/path/to/jira/bin/setenv.sh file you can configure a non-blocking entropy source by adjusting the
JVM_SUPPORT_RECOMMENDED_ARGS variable like: