Open Stack

So when I use Haproxy for LBaaS for Juno, there is a subnet mandatary field that I need to fill in when creating a pool, and later on when I add members, I can use a different subnet(or simply just enter the ip of the member), when adding vip, I can still select a third subnet.  So what is the usage of the first subnet that I used to create pool?  There is no port created for this pool subnet.  I can see that a port is created for the vip subnet that the loadbalancer instance is binding to.
Regards!
Wanjing Xu 		 	   		  
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