1 Reply Latest reply on Oct 10, 2019 5:20 AM by wila

    Guest OS Type "Windows Server 2012" with Windows Server 2016 installed.

    StephenMoll Hot Shot

      I have noticed that some VMs on our system have Windows Server 2016 installed on VMs with the guest type set to "Windows Server 2016 64-bit".

      ESXi is flagging this as a warning, but I note that vSphere doesn't seem to flag this at all.


      In any event I looked around for information on what possible side-effects there could be from this. I found Frank Denneman's blog on this : Impact of mismatch Guest OS type - frankdenneman.nl


      Which suggests there is the potential for degraded performance, but reading it I see that most of the examples are based around a time when there were significant architectural changes in hypervisors and operating systems happening. This got me to thinking that such dire warnings might be overplayed in today's context.


      So given the situation I have with this handful of VMs, is it actually anything to worry about, or should I be making efforts to change it?

        • 1. Re: Guest OS Type "Windows Server 2012" with Windows Server 2016 installed.
          wila Guru
          vExpertCommunity WarriorsUser Moderators



          No need to rush a fix for this.

          It is however recommended to adjust this during a planned maintenance window.

          If it is matching the guest OS that is running then you are less likely to bump into certain support issues. The guest OS is used for a number of things by vSphere (how the virtual hardware looks like and what is installed with VMware Tools to name a few) and if it is set correctly then you are not going to waste time on troubleshooting non-issues.



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