Last week I wrote a little setup script for easing the maintenance of our Linux machines run in a VMWare infrastructure environment. Today, I sat a bit in order to find out if I could furter optimise this script. I came across a little program called vmware-guestd that comes with the VMWare Tools for the virtual environments. The official documentation mentions that this tool allows to read and set information from the host system by using the --cmd parameter of vmware-guestd. However, it is not documented what the commands are. This is not entirely true, since it is mentioned that one can set a machine.id to the configuration and read it with vmware-guestd.

After some hours of googling, I collected the following information:

To read the machine.id that has been added manually to the virtual machines configuration call:

vmware-guestd --cmd 'machine.id.get'

To share some information between a virtual machine and the virtualisation host call

vmware-guestd --cmd 'info-set guestinfo.XXX VALUE'
vmware-guestd --cmd 'info-get guestinfo.XXX'

XXX can be any identifier.

There is a concept called network quarantine, that comes with special commands

vmware-guestd --cmd "nq-set [-n] [new descriptor]"

It appears that these commands are particularly used for software maintenance within guest systems that run within VMWareACE. At least I could not run the provided examplaes with my VMWare Workstation 6beta.

The documentation of VMWare Workstation 6beta lists annother command that allows to manipulate configuration parameters of a virtual machine from within the guest operating system.

vmware-guestd --cmd 'vmx.set_option VMXOPTIONAME OLDVALUE NEWVALUE'

However, there is no documented way to find out about the current status of a VMX option. I tried to use 'vmx.get_option', 'vmx.get' and 'vmx.option' but without success.