"non-persistent storage" warning message is displayed on SAN-booted ESXi host

Products

• VMware vSphere ESXi

Issue/Introduction

Warning message appears on ESXi host booting from SAN.

The message appears such as:
 System logs on host < FQDN / IP address of ESXi host > are stored on non-persistent storage.

 

Environment

VMware vSphere ESXi 7.x
VMware vSphere ESXi 8.x

Cause

The warning message is displayed because scratch space is not configured on SAN-booted ESXi host.

Scratch space is configured on the system partition of device automatically during installation or first boot of  ESXi host ,if the device is considered local.
SAN-booted ESXi host creates the partition on SAN LUN ,which is not a local device, hence scratch space is not automatically configured.

Resolution

Configure scratch space manually.

For more information, see Creating a persistent scratch location for ESXi 8.x/7.x