What is difference between NAS and HDFS?

1) HDFS is the primary storage system of Hadoop. HDFS designs to store very large files running on a cluster of commodity hardware. Network-attached storage (NAS) is a file-level computer data storage server. NAS provides data access to a heterogeneous group of clients.

What is the difference between HDFS and NFS?

This NFS file system is a distributed file system that permits its client to access the file over the network. This file system is an open standard….Difference between HDFS and NFS.

Criteria	HDFS	NFS
Data storage –	Its data blocks are dispersed on the local drives of hardware.	Data is stored on a single dedicated hardware.

What is the difference between NAS?

Both network attached storage (NAS) and storage area networks (SAN) were developed to solve the problem of making stored data available to many users at once….

The Main Differences Between NAS and SAN
NAS	SAN
Data accessed as if it were a network-attached drive.	Servers access data as if it were a local hard drive.

What happens when two clients try to access the same file in the HDFS?

Multiple clients can’t write into HDFS file at the similar time. When a client is granted a permission to write data on data node block, the block gets locked till the completion of a write operation. If some another client request to write on the same block of the same file then it is not permitted to do so.

How do Hadoop MapReduce works?

MapReduce assigns fragments of data across the nodes in a Hadoop cluster. The goal is to split a dataset into chunks and use an algorithm to process those chunks at the same time. The parallel processing on multiple machines greatly increases the speed of handling even petabytes of data.

Is HDFS a database?

It does have a storage component called HDFS (Hadoop Distributed File System) which stoes files used for processing but HDFS does not qualify as a relational database, it is just a storage model.