Connector 6.7.4 Cluster Connection Fails (1 reply)

I have a Percona Multi-Master cluster I am trying to connect to.

These connection strings each work just fine to the individual servers:
string myDBCS = "Server=192.168.100.220;Uid=myuser;Pwd=password;Database=testdb;port=3306;";
string myDBCS = "Server=192.168.100.221;Uid=myuser;Pwd=password;Database=testdb;port=3306;";
string myDBCS = "Server=192.168.100.221;Uid=myuser;Pwd=password;Database=testdb;port=3306;";

But this fails with an "Unable to connect to any of the specified MySQL hosts.".
string myDBCS = "Server=192.168.100.220, 192.168.100.221, 192.168.100.222;Uid=myuser;Pwd=password;Database=testdb;port=3306;";

Any I missing something?

Larry