Tejo, there are two reasons that you would want to use a placement policy.
- Full width blades with 2 mezzanine cards - When you have 2 mezzanine cards a placement policy allows you to specify which mezzanine card to assign a vNIC/vHBA to. By doing this you can better load balance the network and storage traffic. In a placement policy the 2 mezzanine cards are identified as vCon1 and vCon2.
- Dynamic vNIC Connection Policy – When you have a Dynamic vNIC Connection Policy as part of a Service Profile you want to have a placement policy so that the dynamic vNICs are created below the standard vNIC/vHBAs in the PCI order. Dynamic vNIC connection policies are used in the configuration of VN-Link in hardware. This type of policy requires the Palo mezzanine card though.
Other than those two reasons I don't know when you would use a placement policy unless you just wanted to make sure the OS sees the vNICs/vHBAs on specific PCI slots.
The exclude-dynamic comes into play with the Dyamic vNIC Connection Policies I mentioned in option 2 above. Exclude-unassigned would be where you have some that you want to assign (vNICs) but you don not care about where the vHBAs get assigned.
I personally have only had the need to use them in the 2 scenarios above.
With your specific scenario you would use the placement policy to assign some vNICs/vHBAs to the Emulex card (2 max for vNIC and vHBAs) and some to the Palo (dynamic vNIC connection policy or more than 2 vNICs. Or you might want all of your vHBAs to use the Emulex and all of your vNICs to use the Palo.
