What is a block and block scanner in HDFS?

1.	What is a block and block scanner in HDFS?
Answer» Block: In HDFS, a "block" refers to the smallest amount of data that may be read or written. Block Scanner: Block Scanner keeps track of the LIST of blocks on a DataNode and checks them for checksum problems. To save disc bandwidth on the data node, Block SCANNERS USE a THROTTLING TECHNIQUE.

Discussion