Query: select 2gusage,count(2gusage) from demo group by 2gusage; Output: MID 765153 HIGH 18095461 LOW 119069472 NULL 25997075 I tried the below query to find the count of NULL values Query select count(*) from demo where 2gusage is 'NULL'; Output 0 Kindly help me out with the query to find the count of NULL values ... View more

I have a Hbase cluster of 3 nodes. Below are the hostnames and daemons running on that machines. hbase2 - Hmaster,RegionServer, Datanode and Nodemanager hbase 1 - RegionServer,Namenode,Datanode, ResourceManager, NodeManager hbase 3 - RegionServer, Datanode and Nodemanager The moment I enter the run start-hbase.sh script. It throws the below given error 2018-06-13 14:56:52,455 INFO [hbase2:60000.activeMasterManager] retry.RetryInvocationHandler: Exception while invoking getFileInfo of class ClientNamenodeProtocolTranslatorPB over hbase2/10.94.1.119:8020 after 11 fail over attempts. Trying to fail over after sleeping for 17938ms. java.net.ConnectException: Call From hbase2/10.94.1.119 to hbase2:8020 failed on connection exception: java.net.ConnectException: Connection refused; For more details see: http://wiki.apache.org/hadoop/ConnectionRefused. Hmaster is not running. RegionServers are working fine ... View more

Clients are not able to access the Hadoop cluster. I have checked pinging to the server. It works fine. The RPC port is up in the Namenode machine [root@env40-node1 hadoop]# netstat -tupln | grep 8020 tcp 0 0 192.168.150.95:8020 0.0.0.0:* LISTEN 32588/java Client is not able to access the cluster It throws the below given error while accessing HDFS from the client machine [root@env7-head-proxy4 ~]# hdfs dfs -ls / ls: No Route to Host from env7-head-proxy4/192.168.151.48 to 192.168.150.95:8020 failed on socket timeout exception: java.net.NoRouteToHostException: No route to ... View more