Hi donghui zhang,
Welcome to MS Q&A!
If you're seeing the "FNAC virtual machine agent status is not ready" error on a FortiNAC VM deployed in Azure, it indicates that the FortiNAC VM agent is not functioning properly.
Essentially, if the agent is not in a ready state, it is usually due to some corruption of the agent which can be resolved by simply manually reinstalling the agent.
If it is not working, you should reinstall it. If it is still not working after that, there is usually something wrong with the VM image itself which would require support to look into further.
Sometimes a simple restart of the VM can resolve transient issues. Stop and then start the FortiNAC VM in Azure.
Also, please share if your VM was deployed from a specialized image. When deploying a VM from image, a manual installation is required for the Guest Agent as described here: Azure Virtual Machine Agent Overview - Azure Virtual Machines | Microsoft Learn. Is that the process that was used for this Guest Agent's installation?
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