When configuring a connection to Jira, use the following authentication parameters:
for self-managed Jira (Server or Data Center): username (specified in the Jira user profile) and password
for Jira Cloud: user email and API token
Since version 2020.1, TeamCity can report build statuses directly to Jira Cloud in real time. To configure this extra option, you need to provide the Jira Client ID and Server secret when configuring a connection and add a respective build feature.