Oracle Cloud Infrastructure Documentation

Known Issues for Logging

These known issues have been identified in Logging.

Some agent warnings or errors can be ignored

Details
For Linux: When the Unified Monitoring Agent (UMA, or 'agent') restarts or the configuration downloader runs, you might see a warning such as the following in the journalctl logs:
ruby[444986]: Circuit: imds_metadata, Warning: sleep_window: 30 is shorter than time_window: 120; the error_rate would not be reset after a sleep.
This warning likely appears because some circuit breaker parameters are haven't been configured correctly.
For Windows: After you upgrade the agent, you might notice an error event similar to the following: 
The Oracle Unified Agent service terminated with the error: There are no child processes to wait for.
Workaround
You can safely ignore these warnings and errors. They have no effect on agent functionality

Transient Error in UMA in systemd versions older than 251

Details
If the Unified Monitoring Agent (UMA) runs on systemd versions older than 251, you might see an error similar to the following:
Oct 27 08:12:22 sumnegi-instance-20251027-1132 systemd[19432]: unified-monitoring-agent.service: Failed to set up mount namespacing: No such file or directory
Oct 27 08:12:22 sumnegi-instance-20251027-1132 systemd[19432]: unified-monitoring-agent.service: Failed at step NAMESPACE spawning /bin/kill: No such file or directory
This happens because the older systemd version doesn't support the required features for namespace setup.
Workaround
To fix this error, upgrade to systemmd version 251 or later.

Unified Monitoring Agent upgrade failure

Details

Updates to the Unified Monitoring Agent running on the host might not be applied if the Custom Logs Monitoring plugin is disabled in the Oracle Cloud Agent's Management tab. This might result in missing important security patches, bug fixes, and new feature enhancements.

Workaround

Enable the Custom Logs Monitoring plugin.