A list of host/port pairs to use for establishing the initial connection to
the Kafka cluster used for licensing. All servers in the cluster will be
discovered from the initial connection. This list should be in the following
form:
host1:port1,host2:port2,...
Since these servers are just used for the initial connection to discover the
full cluster membership (which may change dynamically), this list need not
contain the full set of servers (you may want more than one, though, in case a
server is down).