Book Image

Monitoring Elasticsearch

By : Dan Noble, Pulkit Agrawal, Mahmoud Lababidi
Book Image

Monitoring Elasticsearch

By: Dan Noble, Pulkit Agrawal, Mahmoud Lababidi

Overview of this book

ElasticSearch is a distributed search server similar to Apache Solr with a focus on large datasets, a schema-less setup, and high availability. This schema-free architecture allows ElasticSearch to index and search unstructured content, making it perfectly suited for both small projects and large big data warehouses with petabytes of unstructured data. This book is your toolkit to teach you how to keep your cluster in good health, and show you how to diagnose and treat unexpected issues along the way. You will start by getting introduced to ElasticSearch, and look at some common performance issues that pop up when using the system. You will then see how to install and configure ElasticSearch and the ElasticSearch monitoring plugins. Then, you will proceed to install and use the Marvel dashboard to monitor ElasticSearch. You will find out how to troubleshoot some of the common performance and reliability issues that come up when using ElasticSearch. Finally, you will analyze your cluster’s historical performance, and get to know how to get to the bottom of and recover from system failures. This book will guide you through several monitoring tools, and utilizes real-world cases and dilemmas faced when using ElasticSearch, showing you how to solve them simply, quickly, and cleanly.
Table of Contents (15 chapters)
Monitoring Elasticsearch
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Command line tools for system and process management


The command line is an invaluable tool for system monitoring. In this section, we'll go over a few basic GNU/Linux command line utilities for system and process management. Knowing these tools is essential for anyone managing an Elasticsearch cluster on GNU/Linux.

top

The top command lists processes with the highest CPU and memory. This tool is useful to determine whether a process other than Elasticsearch is hogging resources, or to check whether Elasticsearch is using an abnormal amount of CPU or memory.

The top command refreshes automatically, so you only have to run it once and watch.

When running the command, you should see the following result:

The top command

Tip

Press Shift+M while top is running to sort processes by those using the most memory instead of CPU.

tail

The tail -f command is useful for viewing log files in real time. Use it to view Elasticsearch log files as follows:

tail -f /var/log/elasticsearch/*

"tailing" Elasticsearch log...