Hi there,
It's not possible to add an IP address to a vSwitch as it has no interfaces, just port groups, and only vmkernel port can be assigned an IP.
To have two VMs talk to each other without leaving the host then you can create a vSwitch with no uplinks, create a VM port group on this vSwitch and add a vNIC into each VM and assign them to this port group. Address them on the same subnet and they should be able to talk to each other, might need to add a route in the OS to facilitate if there are other vNICs connected to other networks.
Hope this helps!
vM
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VCAP-DCD / VCAP-DCA / VCP-CLOUD / VCP-DT / VCP5 / VCP4
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