The first thing one wants to do after upgrading the environment to a newer ESX version, is to upgrade VMware tools on all VMs.  If the environment has a large number of machines, this could be a tedious and time-consuming process.  This is where the ability to upgrade a bunch of machines automatically comes in very handy.  It allows you to select a number of machines and kick off VMware tools upgrade for all of them simultaneously.  There is one problem though: VMware tools require a reboot after install and when a number of them are done together, there is no control over install completion and therefore, over reboots.

While in most environments, you won’t be able to get away with rebooting all VMs without notice, manageable chunks can always be identified where rebooting the whole set at a certain time can be agreed with users in advance.  This is still better than logging into each machine to upgrade the tools.

All that said, I would like to share some tips and dispel some myths as automatic upgrade of a bunch of machines, doesn’t always work as expected.  Sometimes it misses machines or doesn’t even start.  Knowing these will hopefully make troubleshooting of such incidents easier.  So, here goes:

  1. Tip: Select as many machines that can be rebooted without notice and see how many get the tools upgraded successfully.  Note down the ones that didn’t upgrade and upgrade them at the end.
  2. Tip: VMs that started life as physical boxes but were imported into the environment, might have an issue in upgrade tools.  Log into that VM and upgrade manually by clicking “Update Tools” in VMware Tools applet.
  3. Myth: An administrative login session must be running on the VM for it to get its tools upgraded – Not True!  If the VM has a supported OS and has VMware Tools installed, it will upgrade without a logged in user.
  4. Myth: All VMs from the set must have the same family of OS for it to have automatic upgrading – Not True!  VMs with a mix of OSes can be selected together to have their tools upgraded.
  5. Tip: Sometimes, a VM can get confused about it’s OS, which affects VMware tools installs.  It happens because the VM is not quite sure of the OS and it generally when a machine has been imported from an older OS, previously running on a physical box.  To fix this, browse to the datastore then to VMImages and select the VMware Tools ISO for the OS you believe it has.  This time, it should work.
  6. Myth: Linux machines can’t participate in automatic upgrades – Not True!  If the VM is running a supported version of Linux then it should be upgradable in the usual fashion.
  7. Tip: You might find that certain Linux machines don’t let their tools upgraded – In most cases, it’s because the kernel had been recompiled and is so far away from the original in terms of configuration.  In such cases, use the manual upgrade method to upgrade tools on the box.

That’s it for now.  Hope these Tips and Myths will make it easier to diagnose issues while upgrading VMware tools automatically!