This problem occurs after you upgrade all of the nodes in your cluster to
6.2.4 by using rolling upgrades. When you try to use X-Pack machine learning features for
the first time, all attempts fail, though GET _xpack and GET _xpack/usage
indicate that X-Pack is enabled.
Symptoms:
-
Errors when you click Machine Learning in Kibana.
For example:
Jobs list could not be createdandAn internal server error occurred. -
Null pointer and remote transport exceptions when you run machine learning APIs such as
GET _xpack/ml/anomaly_detectorsandGET _xpack/ml/datafeeds. -
Errors in the log files on the master nodes.
For example:
unable to install ml metadata upon startup
Resolution:
After you upgrade all master-eligible nodes to Elasticsearch 6.2.4 and X-Pack 6.2.4, restart the current master node, which triggers the X-Pack machine learning features to re-initialize.
For more information, see Rolling upgrades.