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.

About this task

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 ten, 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 machine s from the vSphere Web Client or by using a PowerCLI script.


Turn off the virtual machine.


  1. Find the virtual machine in the vSphere Web Client inventory.
    1. Select a data center, folder, cluster, resource pool, or host.
    2. Click the Related Objects tab and click Virtual Machines.
  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, or to 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.