Hello Rajesh
I think, you might have configured "dfs.domain.socket.path" as /var/run/hdfs-sockets/datanode Actually ,This is a path to a UNIX domain socket that will be used for communication between the DataNode and local HDFS clients. If the string "_PORT" is present in this path, it will be replaced by the TCP port of the DataNode. Ideally if some port present only , you will get that error.please re-checkonce.. if you delete "/var/run/hdfs-sockets/datanode" (worst condition, if it is corrupted) and start the datanode. Thanks & Regards Brahma Reddy Battula ________________________________ From: Rajesh Thallam [rajesh.thal...@gmail.com] Sent: Wednesday, February 11, 2015 12:09 AM To: user@hadoop.apache.org Subject: Re: Failed to start datanode due to bind exception There are no contents in the hdfs-sockets directory Apache Hadoop Base version if 2.5.0 (using CDH 5.3.0) On Tue, Feb 10, 2015 at 10:24 AM, Ted Yu <yuzhih...@gmail.com<mailto:yuzhih...@gmail.com>> wrote: The exception came from DomainSocket so using netstat wouldn't reveal the conflict. What's the output from: ls -l /var/run/hdfs-sockets/datanode Which hadoop release are you using ? Cheers On Tue, Feb 10, 2015 at 10:12 AM, Rajesh Thallam <rajesh.thal...@gmail.com<mailto:rajesh.thal...@gmail.com>> wrote: I have been repeatedly trying to start datanode but it fails with bind exception saying address is already in use even though port is free I used below commands to check netstat -a -t --numeric-ports -p | grep 500 I have overridden default port 50070 with 50081 but the issue still persists. Starting DataNode with maxLockedMemory = 0 Opened streaming server at /172.19.7.160:50081<http://172.19.7.160:50081> Balancing bandwith is 10485760 bytes/s Number threads for balancing is 5 Waiting for threadgroup to exit, active threads is 0 Shutdown complete. Exception in secureMain java.net.BindException: bind(2) error: Address already in use when trying to bind to '/var/run/hdfs-sockets/datanode' at org.apache.hadoop.net.unix.DomainSocket.bind0(Native Method) at org.apache.hadoop.net.unix.DomainSocket.bindAndListen(DomainSocket.java:191) at org.apache.hadoop.hdfs.net.DomainPeerServer.<init>(DomainPeerServer.java:40) at org.apache.hadoop.hdfs.server.datanode.DataNode.getDomainPeerServer(DataNode.java:907) at org.apache.hadoop.hdfs.server.datanode.DataNode.initDataXceiver(DataNode.java:873) at org.apache.hadoop.hdfs.server.datanode.DataNode.startDataNode(DataNode.java:1066) at org.apache.hadoop.hdfs.server.datanode.DataNode.<init>(DataNode.java:411) at org.apache.hadoop.hdfs.server.datanode.DataNode.makeInstance(DataNode.java:2297) at org.apache.hadoop.hdfs.server.datanode.DataNode.instantiateDataNode(DataNode.java:2184) at org.apache.hadoop.hdfs.server.datanode.DataNode.createDataNode(DataNode.java:2231) at org.apache.hadoop.hdfs.server.datanode.DataNode.secureMain(DataNode.java:2407) at org.apache.hadoop.hdfs.server.datanode.DataNode.main(DataNode.java:2431) Exiting with status 1 hdfs-site.xml <property> <name>dfs.datanode.address</name> <value>hostname.dc.xx.org:50010<http://hostname.dc.xx.org:50010></value> </property> <property> <name>dfs.datanode.ipc.address</name> <value>hostname.dc.xx.org:50020<http://hostname.dc.xx.org:50020></value> </property> <property> <name>dfs.datanode.http.address</name> <value>hostname.dc.xx.org:50075<http://hostname.dc.xx.org:50075></value> </property> Regards, RT -- Cheers, RT