VMware vSphere

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  • 1.  Managing VM startup in a HA cluster

    Posted Apr 11, 2021 10:23 AM

    Good afternoon, dear colleagues.
    Not so long ago, we faced an unplanned power outage in the office, and therefore did not have time to correctly transfer the ESXi hosts to maintenance mode, which in turn are part of the vCenter Server in HA mode. After power-up, not all VMs were able to start correctly, and as a result, they had to be started manually. The official manual states that hosts and VMs located in the HA cluster do not support the autorun function and setting this mode, and by default turn on/off after 120 sec.
    Tell me how then you can configure VM autorun for critical IT services on ESXi hosts, either this is done according to some HA algorithm, or it is impossible, and what are the recommendations for this mode of operation in the HA cluster ?
    1. Let's say we have three ESXi hosts in the HA cluster, after enabling three hosts and after 120 seconds. start all VMs, - will all VMs start on the same ESXi host on which they were shut down ? We have a part of the VM that did not start and ended up on other ESXi hosts.



  • 2.  RE: Managing VM startup in a HA cluster

    Posted Apr 11, 2021 01:43 PM

    HA - other than VM Autostart - is meant for High Availability, and does start VMs - which were running on a failed ESXi host - on other available hosts in a HA cluster. There are many option that can be configured, like restart priorities etc. For details please see vSphere Availability

    André



  • 3.  RE: Managing VM startup in a HA cluster

    Posted Apr 11, 2021 02:40 PM

    RenUser_0-1618151648936.png

    The Virtual Machine Startup and Shutdown (automatic startup) setting is disabled for all virtual machines residing on hosts that are in a vSphere HA cluster. Automatic startup is not supported with vSphere HA.https://docs.vmware.com/en/VMware-vSphere/6.7/com.vmware.vsphere.vm_admin.doc/GUID-7A132146-2779-4F4B-B39D-EE4F129DB79C.html 

    I mean, I need to be sure that, for example, the Domain Controller and DHCP services will start first, Excahnge second and a little later in time, and then the rest of the services.

    Or are there no such settings for delaying the startup time of VMs in a high availability cluster, but only the settings for restarting VMs on other hosts? But I don't need some VMs to start themselves, as I don't have enough system resources if all of a sudden the VMs are consolidated on two of the three hosts. Or just disable HA on the host ?

     



  • 4.  RE: Managing VM startup in a HA cluster

    Posted Apr 11, 2021 02:53 PM

    That's why I mentioned the VM Overrides, where you can configure restart priorities, delays, and even disable the restart for individual VMs.
    Please take a look at these settings in your cluster to see whether these settings meet your requirements.

    André



  • 5.  RE: Managing VM startup in a HA cluster

    Posted Apr 12, 2021 11:26 AM

    If we have vCenter edition Standard, then it turns out that we can not configure the rules for running the VM on the hosts and binding to the hosts for the VM?
    As far as I know, the Standard edition does not support DRS.

     

     



  • 6.  RE: Managing VM startup in a HA cluster

    Posted Apr 12, 2021 01:58 PM

    It's actuelly the ESXi edition which enables DRS, and not vCenter Server.
    Anyway, I don't currently have access to a vSphere environment, but you should be able to configure "VM Overrides" for HA.

    André