You may have an issue which is difficult to troubleshoot and may require an increased logging level to investigate further.
It is well documented here but this article will aim to simplify it:
1. To set the log level to DEBUG in OpsCenter, you will need to add or modify the following entry in the logback.xml of your Opscenter Server (set root level to DEBUG):
2. To set the log level to DEBUG in the agent side of 1 chosen node, you will need to add or modify the following entry in the /etc/datastax-agent/log4j.properties file of the node:
You will need to restart your agent and Opscenter to activate the debug log level.
IMPORTANT: Please only leave the DEBUG mode for the purpose of the investigation/test only, then reverse the change by setting the logging level back to INFO.