Issues can have relationships between themselves. Sometimes, two issues might be related to each other, and in other cases, one issue might be a duplicate of another issue. Instead of capturing all these associations in the issue description or comments, JIRA provides the facility to create links between issues.
Issue linking is enabled by default when you first install JIRA. If for some reason it is disabled, you will need to re-enable it. Issue linking is configured globally, so once it is enabled, issue linking will become available for all projects in JIRA.
You need to be a JIRA Administrator to enable issue linking. To do so, follow the steps below: