Differences between HDFS and NAS are
- In HDFS Data Blocks are distributed across local drives of all machines in a cluster. Whereas in NAS data is stored on dedicated hardware.
- HDFS is designed to work with Map Reduce System, since computation are moved to data. NAS is not suitable for Map Reduce since data is stored separately from the computations.
- HDFS runs on a cluster of machines and provides redundancy using replication protocol. Whereas NAS is provided by a single machine therefore does not provide data redundancy.