@bmoisson @Sumit6620  When you authenticate via NiFi, there is both a client JWT token generated and a server side key  generated on the node on which the authentication was performed.  That Client JWT token can then be used to perform calls to rest-api endpoints on that node only for which that client is authorized.   When you are obtaining your JWT token from an external authentication endpoint, NiFi won't have the server side token need to validate that token and thus rejects that token. You can find the various methods of authentication that can be configured in Apache NiFi here: https://nifi.apache.org/docs/nifi-docs/html/administration-guide.html#user_authentication   If you found that the provided solution(s) assisted you with your query, please take a moment to login and click Accept as Solution below each response that helped. Thank you, Matt ... View more