Hello @Djordje Novakovic ,
Thanks for reaching out.
You may need to use SCOM or other existing monitoring solution to monitor below possible error events from Azure AD proxy connector servers Admin log on-premises. However, our product team is working to introduce this notification system out of box within Azure AD proxy for connectors but unfortunately we don't have ETA.
12015 - The Connector failed to establish connection with the service.
12019 - The Connector stopped working because the client certificate is not valid. Uninstall the Connector and install it again.
12020 - The Connector was unable to connect to the service due to networking issues. The Connector tried to access the following URL
Hope this helps.
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