When i want to start Namenode of Hadoop i'm forced to format it or i'll got the error connection to localhost:9000, so for this reason i will lose all my data storaged in HDFS after formating the Namenode. Because the dir of namenode and datanode were in tmp folder which will be cleaned after every reboot the machine, So how i can resolve this problem in order to start the Namenode service without formating to keep my data on HDFS ? ... View more