@Muhammad waqas
Can you share your DISTCP command?
Make sure the name node are up and running!
Check if the data nodes are in the dfs.exclude
$cat /etc/hadoop/conf/dfs.exclude
It seems your replication factor is higher than the number of data nodes! Can you manually set the replication factor to 1 and retry .
$ hadoop distcp -D dfs.replication=1 hdfs://namenode1:50070/file1 hdfs://namenode2:50070/
Hope that helps