ESXi installation fails at 5% due to faulty SD card

Products

• VMware vSphere ESXi

Issue/Introduction

• When attempting to install an ESXi host, the installation may fail at 5% with the error message "An unexpected error occurred. See logs for details. Exception: Busy."
• This issue can occur when the SD card used for the ESXi installation is faulty or has developed problems over time.

Environment

ESXi host with an SD card as the boot device

Cause

The cause of the installation failure is often a faulty or failing SD card. Over time, SD cards can develop issues that may go unnoticed until the host is rebooted or an upgrade is attempted.

When the ESXi installer attempts to repartition and reformat the SD card during the upgrade process, it encounters problems due to the faulty hardware, resulting in the installation being stuck at 5%.

Resolution

1. Obtain a replacement SD card for the affected ESXi host.
   • Consider replacing the SD cards for both hosts in a two-node cluster, as they likely have similar usage and may fail around the same time.
     
     
2. Boot the affected ESXi host without the ESXi installation ISO attached.
   • If the host fails to boot, it confirms that the SD card has failed.
     
     
3. Attach the ESXi installation ISO to the affected host.
   
   
4. Boot the host from the ISO and proceed with the installation.
   
   
5. Complete the ESXi installation using the new SD card.
   
   
6. Verify that the host is back in production and functioning normally.

Additional Information

• It is recommended to periodically check the health of SD cards used in ESXi hosts to proactively identify and replace failing devices.
• Consider using more reliable storage devices, such as SSD cards, for ESXi installations to reduce the risk of failure.