System event log full.
Had the same thing on a Lenovo (IBM) x3650 M5.
For those curious, in vSphere 6.7 the navigation is:
Monitor > Tasks and Events > Hardware Health > SYSTEM EVENT LOG > RESET EVENT LOG
We are using Lenovo's x240 enterprise chassis and we encountered the same issue.
Resetting the event log worked perfectly. No longer seeing this error message.
you need to run the below command to get that error or notification cleared. I found some thing on web and tried.
you can try these steps. It worked for me too. Thanks to this guy.