ESXi hosts show not responding status in vCenter after upgrade to 8.0.3

Products

• VMware vSphere ESXi

Issue/Introduction

ESXi hosts in your vCenter Server inventory show "Not Responding" status every 10 seconds. The hosts return to "Connected" status and repeat this cycle. This flapping starts after you upgrade ESXi to a newer version.
Virtual machines (VMs) continue to work normally. Guest operations and access are not affected.

Environment

Seen in: vCenter Server 8.0.3 (Build 24022515) managing ESXi 8.0.3 (Build 24022510) hosts after upgrade from ESXi 8.0 Update 2

Cause

Configuration state synchronization issues between ESXi hosts and vCenter Server can occur after ESXi 8.0.3 upgrade. During the upgrade process, configuration changes in the ESXi network stack or management components may create inconsistencies in the cached connection parameters, host database entries, or communication settings stored on either the ESXi host or vCenter Server.
This results in ESXi hosts using stale or incorrect connection information when communicating with vCenter Server, or vCenter Server maintaining outdated host configuration data. The symptoms are similar to scenarios where vCenter Server IP addresses are improperly changed without updating all dependent configurations. These configuration inconsistencies cause intermittent communication failures that interrupt heartbeat communication, leading to the cyclical "Not Responding" status.

Resolution

Primary solution - Disconnect and reconnect hosts

• Log in to vCenter Server using the vSphere Client.
• Navigate to Hosts and Clusters view.
• Right-click the affected ESXi host and select Connection > Disconnect.
• Wait for the host status to show "Disconnected".
• Right-click the host again and select Connection > Connect.
• Monitor the host status to confirm stable "Connected" status.
• Repeat for any additional affected hosts.

Note: This process forces ESXi to push fresh database entries to vCenter and vCenter to push current location and configuration settings to the host, resolving configuration state inconsistencies.

Alternative workaround - Restart management services
If disconnect/reconnect cannot be performed immediately:

• Log in to the ESXi host console via Secure Shell (SSH) or Direct Console User Interface (DCUI).
• Restart the management services by running these commands:

/etc/init.d/hostd restart/etc/init.d/vpxa restart

 

• Check the vCenter Server inventory to confirm improved stability.

Verify resolution

• Monitor affected hosts for at least 30 minutes after disconnect/reconnect.
• Check vCenter Server events for any recurring connection warnings.
• Verify that host heartbeat communications remain stable.

Additional Information

Preventive measures for future upgrades

• Consider performing disconnect/reconnect operations as part of post-upgrade procedures to synch the data between hosts and vCenters.
• Consider performing cold boot of vCenters and ESXi hosts prior to upgrades in order to remove bad cached data
• Document any custom network or management configurations that may need refresh after major ESXi upgrades.
• Monitor host connectivity closely in the first few hours after ESXi upgrades.