This section will not provide in-depth knowledge of the Hadoop architecture, but only a high-level overview so we can understand the following chapters without much difficulty.
For detailed knowledge on this subject, I recommend a study of the book Hadoop: The Definitive Guide, Tom White, O'Reilly Media.
- A node is just a computer containing data that is based on nonenterprise, inexpensive commodity hardware. So, in the following figure, we have Node 1, Node 2, Node 3, and so on.
- A rack is normally a collection of 10 or more nodes physically stored together and connected to the same network switch. So, network latency between any two nodes in a rack is lower than the latency between two nodes on different racks. ...