ESXi Host goes missing from the vCenter server inventory after going unresponsive
Article ID: 443187
Updated On:
Products
Issue/Introduction
- A production ESXi host becomes unresponsive and subsequently disappears from the vCenter Server inventory.
- The host is not visible within its assigned Cluster or Datacenter folder.
- The host appears under the "Discovered Hosts" section within the Auto Deploy configuration in vCenter.
Environment
VMware vSphere ESXi
VMware vCenter Server
Cause
This behavior occurs because the host is a "stateless ESXi Host" provisioned via vSphere Auto Deploy.
When a stateless host goes unresponsive and reboots, it must successfully complete a PXE network handshake to re-register with vCenter. If the host is unable to reach the PXE boot server or fails to obtain an IP address via DHCP during the boot sequence, it cannot retrieve its assigned Image Profile and Host Profile. Consequently, vCenter cannot map the hardware back to its existing inventory object, and the host is relegated to the "Discovered Hosts" staging area.
Resolution
To restore the host to the vCenter inventory, perform the following steps:
1. Verify Hardware Identifiers (MAC Address):
Ensure that the physical MAC address of the ESXi host has not changed at the hardware level.
Auto Deploy utilizes the MAC address as the primary identifier to map a booting host to its existing record in the vCenter inventory. If the MAC address has changed (commonly due to a motherboard replacement, NIC firmware update, or a hardware configuration reset), Auto Deploy will fail to associate the hardware with the existing host object. This causes vCenter to treat the asset as a new, conflicting entity, preventing it from joining the production inventory.
2. Remediate the Unresponsive State and Network Connectivity:
Address the underlying root cause that caused the ESXi host to become unresponsive (e.g., kernel panic, hardware lockup, or storage timeout).
Once the underlying issue is resolved:
- Ensure the host can successfully communicate with the DHCP server to obtain an IP address.
- Verify the host has an uninterrupted network path to the PXE boot/Auto Deploy server.
- When the host successfully completes the PXE boot and retrieves its assigned profiles, it will automatically reappear in the vCenter Server inventory.
Additional Information
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