Do we have to format datanode for HDFS file system or we only need to format namenode

Question

While setting up pseudo or full cluster, do we need to format data node to install HDFS file system or we only have to format namenode.

I am asking this because, I have read this on many blogs that, HDFS stores the data in sequential order on the hard disk and it is an abstract layer which stores data on big blocks rather than default block size storage provided host file system.

If we are not formatting datanode than the powerful feature of HDFS comes to toss.

score 2 · Answer 1 · answered Jan 14 '19 at 19:24

2

Formating and mounting the hard drives is not directly related to formatting HDFS. Conceptually the idea of "formating" is the same. But the two tasks are completely separate with no direct relationship.

The hadoop format command does not format or mount the hard drives. The hard drives should already be formatted and mounted. When you run the format command for HDFS, it is preparing NameNode fsimage file so that it knows where all of the storage blocks are across the data disks.

answered Jan 14 '19 at 19:24

Ajay Kharade

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Thanks for the reply. – Sagar Chawla Jan 15 '19 at 13:06
If you are agree to this, you can accept answer, it will help other people as well. – Ajay Kharade Jan 15 '19 at 13:51

Do we have to format datanode for HDFS file system or we only need to format namenode

1 Answers1