Book Image

MongoDB Administrator???s Guide

By : Cyrus Dasadia
Book Image

MongoDB Administrator???s Guide

By: Cyrus Dasadia

Overview of this book

MongoDB is a high-performance and feature-rich NoSQL database that forms the backbone of the systems that power many different organizations. Packed with many features that have become essential for many different types of software professional and incredibly easy to use, this cookbook contains more than 100 recipes to address the everyday challenges of working with MongoDB. Starting with database configuration, you will understand the indexing aspects of MongoDB. The book also includes practical recipes on how you can optimize your database query performance, perform diagnostics, and query debugging. You will also learn how to implement the core administration tasks required for high-availability and scalability, achieved through replica sets and sharding, respectively. You will also implement server security concepts such as authentication, user management, role-based access models, and TLS configuration. You will also learn how to back up and recover your database efficiently and monitor server performance. By the end of this book, you will have all the information you need—along with tips, tricks, and best practices—to implement a high-performance MongoDB solution.
Table of Contents (17 chapters)
Title Page
Credits
About the Author
About the Reviewers
www.PacktPub.com
Customer Feedback
Preface

Managing chunks


By now, you should be familiar with the notion of chunks in a MongoDB sharded cluster. In this recipe, we will look at how to split chunks and migrate them across shards.

Getting ready

Ensure you have a sharded cluster ready. If you are reusing the setup from the previous recipe, ensure that you drop the database, as such:

use myShardedDB
db.dropDatabase()

Before we import the mock data, enable sharding:

sh.enableSharding('myShardedDB')
 sh.shardCollection('myShardedDB.users', {age: 1})

Finally, we need to import the mock data using the mongoimport utility:

mongoimport -h 192.168.200.200 --type csv --headerline -d myShardedDB -c users chapter_5_mock_data.csv

How to do it...

  1. Connect to the mongos service and inspect the chunks:
sh.status()

--- Sharding Status ---
 sharding version: {
 <-- output truncated -- >
 databases:
 { "_id" : "myShardedDB", "primary" : "shard0002", "partitioned" : true }
 myShardedDB.users
 shard key: { "age" : 1 }
 unique: false
 balancing: true
 chunks...