X-Pack Monitoring screen error after ES upgrade

Hey Tim,

Yes, I see exactly that, using my authentication info with http://es-host:9200/_xpack. That's correct.

Unfortunately I cannot go through monitoring tab in kibana page, who gives always that "Monitoring: Error 404 Not Found: undefined" message.

Of course now the version is 5.5.1 and Build: 15405, but the message is still there.

In kibana.log message I see a repetitive message telling me that "License information could not be obtained from Elasticsearch. [security_exception] missing authentication token for REST request", even though I double checked kibana.yml settings and verified (I guess) user and role info in kibana.

What now? How can I further debug this? Is it really a licensing problem?

Thank you!
Leandro.