[에러] Failure in connecting to Drill: org.apache.drill.exec.rpc.RpcException: CONNECTION

* 아래와 같은 에러 발생 시

$ /usr/local/drill/bin/drill-localhost
Java HotSpot(TM) 64-Bit Server VM warning: ignoring option MaxPermSize=512M; support was removed in 8.0
Error: Failure in connecting to Drill: org.apache.drill.exec.rpc.RpcException: CONNECTION : java.net.ConnectException: Connection refused: localhost/127.0.0.1:31010 (state=,code=0)
java.sql.SQLException: Failure in connecting to Drill: org.apache.drill.exec.rpc.RpcException: CONNECTION : java.net.ConnectException: Connection refused: localhost/127.0.0.1:31010
        at org.apache.drill.jdbc.impl.DrillConnectionImpl.<init>(DrillConnectionImpl.java:167)
        at org.apache.drill.jdbc.impl.DrillJdbc41Factory.newDrillConnection(DrillJdbc41Factory.java:72)
        at org.apache.drill.jdbc.impl.DrillFactory.newConnection(DrillFactory.java:69)
        at org.apache.calcite.avatica.UnregisteredDriver.connect(UnregisteredDriver.java:143)
        at org.apache.drill.jdbc.Driver.connect(Driver.java:72)
        at sqlline.DatabaseConnection.connect(DatabaseConnection.java:167)
        at sqlline.DatabaseConnection.getConnection(DatabaseConnection.java:213)
        at sqlline.Commands.connect(Commands.java:1083)
        at sqlline.Commands.connect(Commands.java:1015)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:498)
        at sqlline.ReflectiveCommandHandler.execute(ReflectiveCommandHandler.java:36)
        at sqlline.SqlLine.dispatch(SqlLine.java:742)
        at sqlline.SqlLine.initArgs(SqlLine.java:528)
        at sqlline.SqlLine.begin(SqlLine.java:596)
        at sqlline.SqlLine.start(SqlLine.java:375)
        at sqlline.SqlLine.main(SqlLine.java:268)
Caused by: org.apache.drill.exec.rpc.RpcException: CONNECTION : java.net.ConnectException: Connection refused: localhost/127.0.0.1:31010
        at org.apache.drill.exec.rpc.user.UserClient$2.connectionFailed(UserClient.java:197)
        at org.apache.drill.exec.rpc.user.QueryResultHandler$ChannelClosedHandler.connectionFailed(QueryResultHandler.java:389)
        at org.apache.drill.exec.rpc.BasicClient$ConnectionMultiListener$ConnectionHandler.operationComplete(BasicClient.java:249)
        at org.apache.drill.exec.rpc.BasicClient$ConnectionMultiListener$ConnectionHandler.operationComplete(BasicClient.java:212)
        at io.netty.util.concurrent.DefaultPromise.notifyListener0(DefaultPromise.java:680)
        at io.netty.util.concurrent.DefaultPromise.notifyListeners0(DefaultPromise.java:603)
        at io.netty.util.concurrent.DefaultPromise.notifyListeners(DefaultPromise.java:563)
        at io.netty.util.concurrent.DefaultPromise.tryFailure(DefaultPromise.java:424)
        at io.netty.channel.nio.AbstractNioChannel$AbstractNioUnsafe.fulfillConnectPromise(AbstractNioChannel.java:268)
        at io.netty.channel.nio.AbstractNioChannel$AbstractNioUnsafe.finishConnect(AbstractNioChannel.java:284)
        at io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:528)
        at io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:468)
        at io.netty.channel.nio.NioEventLoop.processSelectedKeys(NioEventLoop.java:382)
        at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:354)
        at io.netty.util.concurrent.SingleThreadEventExecutor$2.run(SingleThreadEventExecutor.java:111)
        at java.lang.Thread.run(Thread.java:748)
Caused by: java.util.concurrent.ExecutionException: java.net.ConnectException: Connection refused: localhost/127.0.0.1:31010
        at io.netty.util.concurrent.AbstractFuture.get(AbstractFuture.java:47)
        at org.apache.drill.exec.rpc.BasicClient$ConnectionMultiListener$ConnectionHandler.operationComplete(BasicClient.java:225)
        ... 13 more
Caused by: java.net.ConnectException: Connection refused: localhost/127.0.0.1:31010
        at sun.nio.ch.SocketChannelImpl.checkConnect(Native Method)
        at sun.nio.ch.SocketChannelImpl.finishConnect(SocketChannelImpl.java:717)
        at io.netty.channel.socket.nio.NioSocketChannel.doFinishConnect(NioSocketChannel.java:224)
        at io.netty.channel.nio.AbstractNioChannel$AbstractNioUnsafe.finishConnect(AbstractNioChannel.java:281)
        ... 6 more
apache drill 1.11.0
"the only truly happy people are children, the creative minority and drill users"
0: jdbc:drill:drillbit=localhost>
 

* 발생 원인

 -> 클러스터링된 해당 서버와 연결에 실패해서 발생된 에러입니다.

* 조치 사항

 -> 각 서버와 통신에 이상 없는지를 확인합니다.

 -> drill-override.conf 파일을 확인합니다.

  ㄴ 참고 사항

drill.exec: {
  cluster-id: "drillbits1",
  zk.connect: "test1:2181, test2:2181, test3:2181, test4:2181, test5:2181"
}
 

* 위와 같이 각 서버의 호스트명과 포트 번호를 콤마로 구분해서 기입할 때 띄어쓰기를 할 경우 인식하지 못 하므로 주의하세요!