clarify authentication. fix #1568
clarify authentication. fix #1568

replay/metrictank,raintank/raintank-metric,replay/metrictank,raintank/metrictank,raintank/metrictank,replay/metrictank,raintank/raintank-metric,raintank/raintank-metric,raintank/metrictank,raintank/metrictank,replay/metrictank