Mastering Hadoop Snapshot Management

Introduction

Welcome to the magical world of Hadoop Snapshot Management! In this lab, you will embark on a journey through a enchanting forest where you will meet a mysterious tree spirit known as Leafa. Your goal is to learn the art of managing snapshots in Hadoop HDFS while exploring the wonders of this mystical realm.

Skills Graph

%%%%{init: {'theme':'neutral'}}%%%% flowchart RL hadoop(("`Hadoop`")) -.-> hadoop/HadoopHDFSGroup(["`Hadoop HDFS`"]) hadoop/HadoopHDFSGroup -.-> hadoop/snapshot("`Snapshot Management`") subgraph Lab Skills hadoop/snapshot -.-> lab-271907{{"`Hadoop Snapshot Management`"}} end

Creating a Snapshot

In this step, you will learn how to create a snapshot of a directory in HDFS.

Open a terminal and switch to the hadoop user:
```
su - hadoop
```

Create a directory in HDFS:

hdfs dfs -mkdir /user/hadoop/snapshot_demo

Populate the directory with some sample files:

echo "Hello, World" > /home/hadoop/sample.txt

hdfs dfs -put /home/hadoop/sample.txt /user/hadoop/snapshot_demo/

Allow snapshots on the directory:

hdfs dfsadmin -allowSnapshot /user/hadoop/snapshot_demo

Verify that the directory is snapshottable:
```
hdfs lsSnapshottableDir
```

Create a snapshot of the directory:

hdfs dfs -createSnapshot /user/hadoop/snapshot_demo snapshot1

Verify the snapshot creation:

hdfs dfs -ls /user/hadoop/snapshot_demo/.snapshot/snapshot1

Restoring a Snapshot

In this step, you will learn how to restore a directory from a snapshot in HDFS.

Create a directory in HDFS:

hdfs dfs -mkdir /user/hadoop/restored_snapshot_demo

Restore the directory from the created snapshot:

hdfs dfs -cp /user/hadoop/snapshot_demo/.snapshot/snapshot1 /user/hadoop/restored_snapshot_demo

Verify the contents of the restored directory:

hdfs dfs -cat /user/hadoop/restored_snapshot_demo/snapshot1/sample.txt

Deleting a Snapshot

In this step, you will learn how to delete a previously created snapshot in Hadoop's HDFS.

Delete the snapshot created in the first step:

hdfs dfs -deleteSnapshot /user/hadoop/snapshot_demo snapshot1

Verify the snapshot deletion:

hdfs dfs -ls /user/hadoop/snapshot_demo/.snapshot

Summary

In this lab, we delved into the realm of Hadoop Snapshot Management by creating, restoring, and deleting snapshots in HDFS. Through these hands-on exercises, you gained practical experience in handling snapshots, a crucial aspect of managing data in Hadoop. By mastering snapshot management, you are now equipped with a powerful tool for data backup and recovery in your Hadoop ecosystem. Happy exploring the magical world of Hadoop!

Hadoop Snapshot Management