Hbase/OpenTSBD connection refused error

I am new to HBase and OpenTSBD. I followed all of the steps in OpenTSDB Manual: http://opentsdb.net/getting-started.html

However, when I get to the final step, I get the following error:

java.net.ConnectException: Connection refused
    at sun.nio.ch.SocketChannelImpl.checkConnect(Native Method) ~[na:1.7.0_07]
    at sun.nio.ch.SocketChannelImpl.finishConnect(SocketChannelImpl.java:692) ~[na:1.7.0_07]
    at org.apache.zookeeper.ClientCnxn$SendThread.run(ClientCnxn.java:1146) ~[zookeeper-3.3.4.jar:3.3.3-1203054]
2012-10-22 09:52:45,715 INFO  [main-SendThread(localhost:2181)] ClientCnxn: Opening socket connection to server localhost/127.0.0.1:2181
2012-10-22 09:52:45,716 WARN  [main-SendThread(localhost:2181)] ClientCnxn: Session 0x0 for server null, unexpected error, closing socket connection and attempting reconnect

Could you please tell me what is causing the issue? Thanks for your help!

Solution

This indicates that it's having trouble connecting to ZooKeeper. If you're running on a single-node setup, you probably haven't started HBase, or it's not running properly. Check HBase's logs.