I have a 3 node hadoop cluster CDH 4.4 and every few days or when ever I load some data through sqoop or query through hive , sometimes I get the following error -
Call From <<server 1>> to <<server 2>> failed on connection exception: Connection refused

This has become so frequent. What can be the reasons and how should I troubleshoot this? Is it the hardware or network can be the most common problem/issue with this kind of error. Please advise.


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