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  • 1.  3 Node Cluster Fail over

    Posted Dec 06, 2023 09:52 AM

    Hello 

     

    I have setup a 3 Node Cluster with vSAN, with 1 Management host. Failover is working fine when I power off 1 host all VM switches between 2 hosts, but if I power off 2 host, then VM becomes disconnected. Is this expected 



  • 2.  RE: 3 Node Cluster Fail over

    Posted Dec 06, 2023 02:53 PM
    Yes, the 3 node cluster is the recommended minimum for this reason


  • 3.  RE: 3 Node Cluster Fail over

    Posted Dec 08, 2023 10:27 PM

    , In a 3-node vSAN cluster and using the default vSAN storage policy (FTT=1, FTM=RAID1), the data can is basically spread across all 3 nodes as data-replica+data-replica+witness-component.

     

    For this data to be accessible requires 1. at least one data-replica AND 2. Quorum (>50% of components accessible e.g. any 2 of the 3 here either data-replica+data-replica OR data-replica+witness-component).

     

    When you power off 1 node, requirements 1. and 2. are met, however if you power off 2 nodes then requirements 1. may/may not be met but it doesn't matter because requirement 2. will not be met (and all of these objects will become inaccessible and the VMs not be able to power-on/restart).