3 Replies Latest reply on Mar 13, 2019 6:12 PM by daphnissov

    vMotion scenario

    Gawnet Lurker

      Hi,

       

      I have 1 master VM with 1 slave VM, so when Master vm  goes down, it is automatically vMotion into slave VM. Now I want to add another Master VM and run it as DB server and when it goes down I want it to be migrated to the same slave VM as existing master VM. Can this be done?

       

      Scenario:

      1 master vm & 1 slave vm is in pair already.

      Add 1 more master vm to be covered by the same slave vm.

       

      Thanks,

        • 1. Re: vMotion scenario
          daphnissov Guru
          Community WarriorsvExpert

          What do you mean by "master" and "slave" in this sense? What application are we talking about? When you use the term "vMotion" it means something very specific, which is the live migration of a running VM from one ESXi host to another. It does not mean to fail-over (in any sense) to another VM, regardless of that application. Until you can clarify what you're looking to do (and use the correct terminology), we don't know what you're asking.

          • 2. Re: vMotion scenario
            Gawnet Lurker

            Hi,

            Thanks for replying.

             

            Ok the term "Master" and "Slave" are master as running production VM and slave as backup vm for vMotion. So when running vm dies or lost connection, it gets automatically migrated to that "slave" vm which is not in production and using very little bit of resource. So it is just active-standby situation to clarify.

             

            The total resource pool we have is 512GB of ram currently and master and slave are allocated 256GB each. Master VM (production vm) is using almost every ram resource allocated and slave VM is using 50GB / 256 GB, so slave has capacity of 200GB of ram. So we are planning to add 1 more DB server and share that remaining 200GB of ram from slave VM.

             

            But the problem is that when that newly added DB server (probably will be allocated 128GB ram), vm, is down, will it be able to migrated into the slave VM.

            Since I have not experienced such environment, I am searching the similar situation but couldn't find it.

             

            Will this plan be able to pull off?

             

            Thanks,

            • 3. Re: vMotion scenario
              daphnissov Guru
              vExpertCommunity Warriors

              Ok the term "Master" and "Slave" are master as running production VM and slave as backup vm for vMotion. So when running vm dies or lost connection, it gets automatically migrated to that "slave" vm which is not in production and using very little bit of resource. So it is just active-standby situation to clarify.

              So, again, you're misunderstanding how vMotion works. A "backup VM for vMotion" doesn't/can't work because vMotion isn't a reaction to a failure (however you determine that) of a VM. That's what either vSphere HA does or some mechanism at the application layer does. I don't know what this application you have is, but what you need to look into is an application-level high availability solution because vMotion won't help you there.