Hi @Raj Kumar, Thanks for the reply. Our data was showing as missing blocks and hence we restored the data from our backup(present in different server). Due to this, Blockpool name had the IP of the backup server which we did not notice. We proceeded to restart Hadoop services and faced the following errors in the namenode logs, ERROR org.apache.hadoop.hdfs.server.datanode.DataNode: Exception in BPOfferService for Block pool BP-xxxxxxx-10.x.x.x-xxxxxxxxxx (Datanode Uuid 0fxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxx) service to nn01/10.x.x.x:9000 java.lang.IllegalStateException: com.google.protobuf.InvalidProtocolBufferException: Protocol message was too large. May be malicious. Use CodedInputStream.setSizeLimit() to increase the size limit. at org.apache.hadoop.hdfs.protocol.BlockListAsLongs$BufferDecoder$1.next(BlockListAsLongs.java:332) at org.apache.hadoop.hdfs.protocol.BlockListAsLongs$BufferDecoder$1.next(BlockListAsLongs.java:310) at org.apache.hadoop.hdfs.protocol.BlockListAsLongs$BufferDecoder.getBlockListAsLongs(BlockListAsLongs.java:288) at org.apache.hadoop.hdfs.protocolPB.DatanodeProtocolClientSideTranslatorPB.blockReport(DatanodeProtocolClientSideTranslatorPB.java:190) at org.apache.hadoop.hdfs.server.datanode.BPServiceActor.blockReport(BPServiceActor.java:475) at org.apache.hadoop.hdfs.server.datanode.BPServiceActor.offerService(BPServiceActor.java:688) at org.apache.hadoop.hdfs.server.datanode.BPServiceActor.run(BPServiceActor.java:823) at java.lang.Thread.run(Thread.java:748) After this, we have manually changed the Blackpool's name to the right IP and restarted services but still, we are facing the same issue. The whole of the data is showing as missing in namenode UI. Please help us on this, If you need any more details, please feel free to mail at densingmoses123@gmail.com we can have a quick discussion regarding this, Thanks in advance. ... View more