One or more hosts did not report their OS Distribution. This is likely due to running an outdated version of the cloudera agent. Please run the Host inspector to check the Agent versions.
Any ide why i am getting this error ? Because i havent changed any new packages.
If you run the host inspector, then it will show you a detailed report about everything it found on that as well as all other hosts and from that report you can figure out what's wrong.
The other option could be to restart agent on that particular node.
I had this error, because my agent was running on Ubuntu 18.04, not 16.04 which is probably the only one supported.
I suppose this is a bug, in which user is informed about some communication problems, when actually it's just compatibility issue.