The vmx.log.rotateSize parameter specifies the log file size at which the switch to new log files happens for the logs for individual virtual machines. Use this parameter together with the vmx.log.keepOld parameter to ensure acceptable log file sizes without losing critical logging information.

The vmx.log.keepOld parameter determines how many virtual machine log file instances the ESXi host retains before overwriting the first log file. The default value of vmx.log.keepOld is 10, a suitable number to properly log complex operations such as vMotion. You must increase this number significantly when you change the value of vmx.log.rotateSize.

This procedure discusses changing the virtual machine rotate size on an individual virtual machine.

To limit the rotate size for all virtual machines on a host, edit the /etc/vmware/config file. If the vmx.log.KeepOld property is not defined in the file, you can add it. You can use a PowerCLI script to change this parameter for selected virtual machines on a host.

You can use the log.rotateSize parameter to affect all log files, not just the virtual machine log files.

You can change the value of vmx.log.rotateSize for all virtual machines from the vSphere Client or by using a PowerCLI script.


Turn off the virtual machine.


  1. Log in to a vCenter Server system using the vSphere Client and find the virtual machine.
    1. In the Navigator, select VMs and Templates.
    2. Find the virtual machine in the hierarchy.
  2. Right-click the virtual machine and click Edit Settings.
  3. Select VM Options.
  4. Click Advanced and click Edit Configuration.
  5. Add or edit the vmx.log.rotateSize parameter to the maximum file size before log information is added to a new file.

    Alternatively, you can add or edit the first log file if you have more log files than the vmx.log.keepOld parameter specifies.

    Specify the size in bytes.
  6. Click OK.