A SQL Server instance has been added using the Database Installer Wizard. The "OS Monitoring" was selected under HostCredentials with the correct username and password to login to the monitored host.
After the instance has been created, both "CPU Load (%)" and "Memory (%)" metrics show "n/a".
The following error is written in the Agent logs:
Credentials are used for the new Infrastructure cartridge to do the new OS monitoring (remote monitoring).
The credentials are stored in lockboxes and are released to the FglAM (Agent Manager) for their use.
If the monitored host is running Windows 2008 and above, check this knowledge base article to ensure that WinRM + WMI has been configured correctly.