HDFS write operation progress

The progress of writing to HDFS is going as this image.

• The HDFS Client requests to write a file block.
• The NameNode responds to the Client with the DataNode to which to write the block.
• The Client requests to write the block to the specified DataNode.
• The DataNode opens a block replication pipeline with another DataNode in the cluster, and this process continues until all configured replicas are written.
• A write acknowledgment is sent back through the replication pipeline.
• The Client is informed that the write operation was successful.