An intermittent IMM_Network0 `Device Unavailable` alert is generated in monitoring tools (e.g., ScienceLogic) for VMware ESXi hosts.

Products

• VMware vSphere ESXi 8.0

Issue/Introduction

• Error: Device Failed Availability Check: Component device #### is not available (IMM_Network0).
• Availability App ID #### running on parent DID #### returned no data.
• Alerts appear periodically and may clear automatically.

Environment

ESXi 8.0.x

Cause

The alert is typically triggered when a VMkernel adapter (e.g., vmk99) is configured on a port group that is not connected to any physical vmnics (uplinks). The monitoring tool attempts to check the availability of this interface, and because it has no physical path, it returns no data, triggering the 'Device Unavailable' status.

Resolution

Consult the hardware vendor and internal networking team regarding the operational requirement for the vmk## port group. 

Additional Information

Note: If it is determined to be unnecessary and lacks physical connectivity, remove the VMkernel adapter vmk## to stop the monitoring notifications. 

Follow these steps to remove the VMkernel adapter:

1. Log in to the vSphere Client.
2. Navigate to Host > Configure > Networking > VMkernel adapters.
3. Identify the VMkernel adapter triggering the alert (e.g., vmk99).
4. Review the associated Virtual Switch and Physical Adapters to confirm no active uplinks exist.
5. Select the adapter and click Delete.

If further assistance is needed, see Contact Broadcom Support.