If you do not configure system logging with the correct log destination on the ESXi host, you receive an event error message. This error occurs if neither of the Syslog options Syslog.global.logDir or Syslog.global.logHost are set.

You see the warning on your Summary tab of a specific (or all) hosts in your VMware ESX infrastructure:

System logging not Configured on host 

Cause

This issue occurs when the default logging location is not configured in the ESXi host, usually after upgrading from ESXi 4.x to 5.x, or even after a major restart of all physical hosts in your VMware ESX infrastructure.

Resolution

To resolve this issue, configure the default logging location in the ESXi host. To configure the default logging location in the ESXi host:

• Navigate to Configuration > Software > Advanced Settings > Syslog > Global on each physical host affected, on vSphere Client or vSphere Web Client.
• Set the type of the Syslog.global.logDir parameter to []/scratch/log. In this case, the logs reside on the local disk.
• If []/scratch/log does not work, just enter the path of a predefined folder on a specific folder, for example: [LUN01] Host1Logs, where Host1Logs is the name of the folder that resides on datastore [LUN01].

Note: If you want to send the logs to a different datastore, set the type of the Syslog.global.logDir parameter to the complete path where you want to store the log files. For example, [Datastore1]/logs or even [Datastore1] logs. The location of the datastore should be unique to each ESXi host (the logs could reside on the same datastore, but they need to be in different folders).

Do not specify the same log directory to multiple hosts, doing so may result in a crash or kernel panic.

Additional Note

• Syslog.global.logDir - The datastore path to the directory where output logs reside.
• Syslog.global.logHost - The remote host where output logs reside.