Hi Andreas,
I am sorry, I not able to confirm your detection in both log files. I compared the current logs on both systems again. The mentioned log entry can be found every minute on the working and the failing server:
good log:
bad log:
As I already mentioned: all Oracle services are running for several hours properly. There must something happening in between that causes a failure of the Oracle plugin… Is it possible to increase the log level of the Checkmk agent?