Increase the availability of vCenter Server

Version 7


    The vCenter Server availability could be necessary in most cases and critical for large environment (or where a lot of services depends on it).

    In small environment, usually, this not so critical, because most of the VMware function still work also without vCenter Server (for more info see vCenter Server Design: Physical vs Virtual )


    There are at least three solutions to increase the availability for vCenter Server:


    • use a VM for vCenter Server and use VMware HA

    • use vCenter Server Heartbeat product

    • use a MSCS solution for vCenter (unsupported from vSphere version)



    VMware HA


    Only usable when vCenter Server is a VM!

    VMware HA require vCenter Server only for the initial setup and configuration.

    Than it can work on ESX in a distributed mode, and vCenter Server is not needed to ensure the correct work of HA.

    For this reason VMware HA can handle also vCenter Server restart (in this case the downtime could be some minutes...)


    IMHO, for small/medium environment I prefer the VMware HA solution... very simple and cheap.

    Be sure to have also the vCenter DB on your VM, or you have to find a HA solution also for your DB.



    vCenter Server Heartbeat


    In this case vCenter Server (the primary instance) could be a VM or a physical system. The secondary must be a VM!

    Optimize availability and resiliency for VMware vCenter Server in any situation. VMware vCenter Server Heartbeat delivers the maximum uptime for your virtual datacenter infrastructure, ensuring consistent operation, even when VMware vCenter Server is threatened by unplanned or planned downtime.



    MSCS or Failover Cluster - Reference Implementation: Clustering VirtualCenter 2.5 Using Microsoft Cluster Services


    In this case vCenter Server (both the primary or the secondary node) could be a VM or also a physical system.

    To implement a Microsoft cluster solution you also need at least Windows Server Enterprise Edition.

    Note that vCenter Server 2.5 is supported only on Windows Server 2003 or Windows Server 2003 R2.

    Instead vCenter Server 4.0 is supported also on Windows Server 2008.


    Similar to this solution is the usage of other cluster solutions, for example Veritas Cluster:,289142,sid94_gci1341780,00.html


    This solution is now unsupported:{}

    vCenter Server 4.x has not been qualified with third party clustering products such as Microsoft Clustering Service and Veritas Cluster Services. VMware does not support third party clustering products. - Supported vCenter Server high availability options



    Why not VMware FT?

    Is it a good choice-using FT for virtual vCenter server redundancy?

    Not yet... vCenter Server 4.0 require 2 vCPU (expecially if you have also a local DB).

    VMware FT actually can work only with VM single vCPU. So or you keep an unsupported vCenter Server (because for a small environment vCenter Server may "work" also with a single vCPU), or you cannot use VMware FT.


    For more information on FT see: VMware FT