Enabling Connectivity between Salesforce and Jira via OAuth 2.0 Authentication
Some features like Jira Service Management Forms require authentication to Jira via OAuth 2.0. This page describes the steps to authenticate to Jira from Salesforce using Named Credentials and OAuth 2.0 (for more details, please refer to OAuth 2.0 Apps in Jira Cloud and https://confluence.atlassian.com/adminjiraserver/jira-oauth-2-0-provider-api-1115659070.html).
Note that OAuth 2.0 is optional and replaces the authentication steps for OAuth 1.0 described here Enabling Connectivity between Salesforce and Jira.
For more information on setting OAuth 2, please refer to: