Summary
This error points towards intermittent connection issues between Runecast Analyzer and the scanned vCenter server. It can be solved by increasing the timeout limit for data collection.
Problem
The error manifests in the Runecast Web interface in the Notification area:
This line appears in /var/log/rca-app/rca-app.log:
2025-09-17 11:38:29.343 INFO - [threadPoolTaskExecutor-3] - g:87 - Scan of <vCenter FQDN> failed with client preventable error: Unable to connect to vCenter: Connection to vCenter timed out.
Troubleshooting steps
First, verify if Runecast Analyzer can communicate with the vCenter server:
- Log in to the Runecast Web interface
- select Menu > System Settings > Connected systems
- In the list of the vCenter servers, check if the impacted vCenter server is marked with the
symbol
If this is not the case, check if the Network connectivity is configured according to the User Guide.
Resolution
- If SSH on your Runecast instance is not enabled, enable it by following the steps in the User Guide.
- Increase the timeout limit with this command
- sudo -u postgres psql -d rcdb -c "UPDATE keyvalue SET jsonvalue = 900000 where key = 'vcenter.request.timeout.ms'"
- Restart the rca-app service with this command
- sudo systemctl restart rca-app.service
- Wait for the service to restart, log in to the Web interface, and trigger analysis of the impacted vCenter server.
What's next
If this article did not help, please email support@runecast.com to open a support ticket, mention that this article was used, and include
Also, generate and upload a support bundle.
