Network setup for VMware and VCS

Hi,

I am trying to set up a cluster consisting of four VMware VMs. I am still having problems finding how to set up the network connections for these systems.
I have read that we need vNetwork Distributed Switches for this. Is that correct? We are installing this into an existing ESX infrastructure and we do not have any spare NICs anymore. So I suppose we have to move some of the NICs to the new VDS.

I would be really grateful if you could help me, or poiunt me in the right direction.

Regards
Thomas

ESX 5.x
VCS 6.0.2
RHEL 6