ESXi host loads default configuration (DHCP) after reboot due to missing encryption.info

Products

• VMware vSphere ESXi

Issue/Introduction

After an ESXi reboot, hosts with TPM enabled may lose all custom configurations, including IP settings and passwords, reverting to a DHCP state.

Environment

VMware ESXi 9.x

Cause

This is caused by a failure to save encryption keys during the previous shutdown.

The /tmp ramdisk is 100% full. This prevents the system from writing the /encryption.info file to the bootbank during shutdown/restart.

 

Resolution

• Restore host configuration if a backup exists.
• Investigate the root cause of /tmp ramdisk exhaustion to prevent recurrence.