Osquery API endpoints in Fleet are not versioned like the Fleet user API. Let me know that works.
That seems to be the issue AFAICS (it expects a JSON body but nginx is returning a not found page?)
<html> <head><title>404 Not Found</title></head> <body> <center><h1>404 Not Found</h1></center> <hr><center>nginx</center> </body> </html> W0903 19:12:55.460351 269113 tls_enroll.cpp:101] Failed enrollment request to <https://ip:8090/api/latest/osquery/enroll> (Cannot parse JSON: Invalid value. Offset: 0) retrying...
curl -k -v -X POST <https://IP:8090/api/v1/osquery/enroll>
That should just be:
Can you run again with
to see if you're getting the same error now that the endpoint is correct?