6 Replies Latest reply on Dec 12, 2019 7:22 AM by miladmeh8

    3 hosts design

    miladmeh8 Novice

      Hi all,

      I have question about designing a vSAN architecture with 3 hosts.

      I have 3 identical hosts in one cluster and i have a management cluster which is including vcenter and some management applications.

      I want to know is it possible to have 2 witness within my environment one of them virtual appliance which will be located on the management cluster and the other one will be the physical in the vSAN cluster?


      Thank you

        • 1. Re: 3 hosts design
          T180985 Hot Shot

          You dont need a witness host/appliance with a 3 host vSAN setup

          • 2. Re: 3 hosts design
            miladmeh8 Novice

            Yes I know but in this situation I will have just one witness per object, I need to have 2 witness node per object

            • 3. Re: 3 hosts design
              T180985 Hot Shot

              The witness (object) is used for a tie break situation. If you found yourself with an outage and 2 separate Witnesses then depending where the outtage occured the system might not be able to break the tie and you could end up with a split brain situation.
              You only want 1


              Its just not possible as the management cluster isnt part of the compute cluster so it would be a completely seperate vSAN datastore

              1 person found this helpful
              • 4. Re: 3 hosts design
                TheBobkin Virtuoso
                VMware EmployeesvExpert

                Hello miladmeh8


                Are you asking can you have 2 Witnesses in 1 vSAN cluster? (No)

                Or are you asking can you run the Witness VM at one site and have it registered as a 'host' on another site?(Yes)

                Please if you could clarify if by 'physical host' you mean the logical virtual-host the Witness node gets registered in inventory as or a physical server with a Witness iso installed.



                1 person found this helpful
                • 5. Re: 3 hosts design
                  depping Champion
                  User ModeratorsVMware Employees

                  Why would you need 2 witnesses? Do you want to increase availability? if so then you need to increase the number of hosts so you can do FTT=2!

                  • 6. Re: 3 hosts design
                    miladmeh8 Novice

                    Yes I want to just increase availability. Yes you are right Duncan, in this situation i can not have 2 witnesses without increasing number of hosts.

                    Thank you