Im not udnerstanding why i would want to use a Layer 4 HLB device for Exchange 2013? From my understanding Layer 4 doesnt have the ability to look at what the client is requesting from the serer and make decisions accordinly. We have multiple services running on Exchange 2013, (OWA,EAS,EWS) if one of the services went down, for example EWS, would a layer 4 load balancer be able to route EWS request from clients to a working EWS service while still distributing traffic evenly for the reamining working services across the CAS arrays? If not i think i would stick with using a layer 7 HLB
Thanks
Bulls on Parade