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Try by configuring the order to negotiate authentication by adding the following property to the JVM configuration and re-starting Jira:

-Dsvnkit.http.methods=Basic,Digest,Negotiate,NTLM

Please, read this Atlassian's documentation for how to add the property above to  your Jira instance configuration startup:

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and verify that the required configuration is present there.

Error: svn: E215000: Credential data unavailable

• Set an URL as svn-ssh://my.server.addr/foo/bar (no username in the URL)
• Add the username you want to connect with in the Basic Authentication section.
• Copy the rsa_id file to the /var/atlassian/application-data/jira and then specified /var/atlassian/application-data/jira/rsa_id in the field for the key