If JIRA is picked as the Defect Tracking system, then a Zephyr Plugin needs to be installed on your JIRA installation in order to track defect metrics along with all the other testing related metrics in Zephyr Dashboards. All other features of the Zephyr-JIRA integration are available without installing the plugin. Please note that only JIRA v3.8 and above are supported.
Prepping JIRA
Install JIRA if you have not done so already
Please ensure that JIRA remote calls are enabled, as discussed in JIRA documentation
a) login in as admin on JIRA and click on Administration

b) Click on General Configuration under Global Settings

c) Make sure Accept remote API calls is ON

Installing Plugin
Download the JIRA Zephyr plugin zip suitable for your version of JIRA
View your JIRA plugin Licenses
To install the plugin:
a) Stop JIRA
b) Copy the downloaded Zephyr plugin jar files into the JIRA directory $JIRA_HOME/atlassian-jira/WEB-INF/lib/ where $JIRA_HOME is the folder where JIRA is installed
c) Start JIRA
The JIRA Zephyr plugin is initialized during JIRA start-up.