Welcome to the community,
As i know the both nic will work together. They both will provide the network services to all of your virtual machines running in the infrastructure. i.e : In case of 1 nic stop working or out of network (due to cable cut/ loose connection etc etc ) the other is going to handle all the load on the other one.
Hope you got what you want.
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Anjani Kumar | VMware vExpert 2014-2015-2016 | Infrastructure Specialist
Twitter : @anjaniyadav85
Website : http://www.Vmwareminds.com