我通过 SSH 进入远程 Ubuntu 虚拟机并尝试使用以下命令加载一些数据：
$ curl -X 'POST' -H 'Content-Type:application/json' -d @quickstart/wikiticker-index.json localhost:8090/druid/indexer/v1/task
curl: (7) Failed to connect to localhost port 8090: Connection refused
我该怎么做才能连接？
以下是我在该目录中运行的内容：
java `cat conf-quickstart/druid/historical/jvm.config | xargs` -cp "conf-quickstart/druid/_common:conf-quickstart/druid/historical:lib/*" io.druid.cli.Main server historical
java `cat conf-quickstart/druid/broker/jvm.config | xargs` -cp "conf-quickstart/druid/_common:conf-quickstart/druid/broker:lib/*" io.druid.cli.Main server broker
java `cat conf-quickstart/druid/coordinator/jvm.config | xargs` -cp "conf-quickstart/druid/_common:conf-quickstart/druid/coordinator:lib/*" io.druid.cli.Main server coordinator
java `cat conf-quickstart/druid/overlord/jvm.config | xargs` -cp "conf-quickstart/druid/_common:conf-quickstart/druid/overlord:lib/*" io.druid.cli.Main server overlord
java `cat conf-quickstart/druid/middleManager/jvm.config | xargs` -cp "conf-quickstart/druid/_common:conf-quickstart/druid/middleManager:lib/*" io.druid.cli.Main server middleManager
运行完上面每一java...行后，它开始重复以下内容：
2017-04-28T23:51:13,769 INFO [main-SendThread(localhost:2181)] org.apache.zookeeper.ClientCnxn - Opening socket connection to server localhost/127.0.0.1:2181. Will not attempt to authenticate using SASL (unknown error)
2017-04-28T23:51:13,769 WARN [main-SendThread(localhost:2181)] org.apache.zookeeper.ClientCnxn - Session 0x0 for server null, unexpected error, closing socket connection and attempting reconnect
java.net.ConnectException: Connection refused
at sun.nio.ch.SocketChannelImpl.checkConnect(Native Method) ~[?:1.8.0_131]
at
sun.nio.ch.SocketChannelImpl.finishConnect(SocketChannelImpl.java:717) ~[?:1.8.0_131]
at org.apache.zookeeper.ClientCnxnSocketNIO.doTransport(ClientCnxnSocketNIO.java:361) ~[zookeeper-3.4.9.jar:3.4.9-1757313]
at org.apache.zookeeper.ClientCnxn$SendThread.run(ClientCnxn.java:1141) [zookeeper-3.4.9.jar:3.4.9-1757313]