Hi,
IMO, with DVS the management overhead related creating and configuring virtual machine portgroup is reduced. If your you VCVA is on the same network as rest of your VM or Infra VMs then to ensure that the same portgroup is available on other ESXi hosts for seamless vMotion I would migrate the VCVA on DVS. However if there arent many VMs on the network that VCVA uses then you might consider keeping the VCVA VM on vSS but make sure that a portgroup with the same name exists on other hosts so that the VM can be vMotioned to other hosts.
-f10
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About VMware Virtualization on NetApp