The load balancer makes its decision as to which node to connect to, based on the number of active connections on each node.
It will choose the node with the least number of connections.

In order to do this it must make a connection to each node  in a group.

The load balancer will need an account on the database server with a password associated with it.

The account is:
user = loadbalancer

please contact an administrator for the password associated with the account.
631-344-2499

The load this operation creates is minimal.

so

something like
 grant process on *.* to 'loadbalancer'@'%.bnl.gov' identified by 'CALL 631-344-2499';
of coarse the location should be local.