How to Install and Use Gremlin on Microsoft Azure

How to Install and Use Gremlin on Microsoft Azure
Last Updated:
Categories: Chaos Engineering

Introduction

Follow this guide to install and use Gremlin on Microsoft Azure and perform a Chaos Engineering experiment using a Gremlin CPU Attack.

Prerequisites

Before you begin this tutorial, you'll need the following:

  • An Ubuntu 16.04 server
  • A Gremlin account (sign up here)
  • A Microsoft Azure account
  • The apt-transport-https package to be able to install gremlin from our repo via HTTPS.

Step 1 - Installing the Gremlin Daemon and CLI

First, add the Gremlin Debian repository:

1echo "deb https://deb.gremlin.com/ release non-free" | sudo tee /etc/apt/sources.list.d/gremlin.list

Import the repo’s GPG key:

1sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys C81FC2F43A48B25808F9583BDFF170F324D41134 9CDB294B29A5B1E2E00C24C022E8EF3461A50EF6

Then install the Gremlin agent and CLI:

1sudo apt-get update && sudo apt-get install -y gremlind gremlin

After you have created your Gremlin account (sign up here) you will need to find your Gremlin agent credentials. Login to the Gremlin App using your Company name and sign-on credentials. These were emailed to you when you signed up to start using Gremlin.

Navigate to Team Settings and click on your Team. Make a note of your Gremlin Secret and Gremlin Team ID.

Then initialise Gremlin and follow the prompts:

1gremlin init

You are now ready to create attacks using the Gremlin App.

Step 2 - Creating attacks using the Gremlin App

Login to the Gremlin App using your Company name and sign-on credentials. These details were emailed to you when you created your Gremlin account.

Select Create Attack in the Gremlin App.

Example: The Hello World of Chaos Engineering (a CPU attack)

You can use the Gremlin App or the Gremlin API to trigger Gremlin attacks. You can view the available range of Gremlin Attacks in Gremlin Help.

The Hello World of Chaos Engineering is the CPU Resource Attack. To create a CPU Resource Attack select Resource and then CPU in the dropdown menu.

gremlin cpu

The CPU Resource Attack will consume CPU resources based on the settings you select. The most popular default settings for a CPU Resource Attack are pre-selected, a default attack will utilize 1 core for 60 seconds. Before you can run the Gremlin attack you will need to click either Exact hosts to run the attack on or click the Random attack option.

Click Exact and select a target from the list.

Your attack will begin to run, you will be able to view its progress via Gremlin Attacks in the Gremlin App.

On your server, run top to check the impact of the Gremlin Attack:

bash
1top
2
3top - 06:26:47 up 7 days, 7:00, 1 user, load average: 0.28, 0.07, 0.02
4Tasks: 105 total, 1 running, 104 sleeping, 0 stopped, 0 zombie
5%Cpu(s): 79.7 us, 20.3 sy, 0.0 ni, 0.0 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st
6KiB Mem : 1016120 total, 127140 free, 93956 used, 795024 buff/cache
7KiB Swap: 0 total, 0 free, 0 used. 712192 avail Mem
8
9 PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
1023768 gremlin 20 0 13268 11136 3576 S 99.3 1.1 0:14.05 gremlin
1123766 root 20 0 40388 3600 3072 R 0.3 0.4 0:00.03 top
12 1 root 20 0 37760 5760 3940 S 0.0 0.6 0:13.74 systemd
13 2 root 20 0 0 0 0 S 0.0 0.0 0:00.00 kthreadd
14 3 root 20 0 0 0 0 S 0.0 0.0 0:01.28 ksoftirqd/0
15 5 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 kworker/0:0H
16 7 root 20 0 0 0 0 S 0.0 0.0 0:06.14 rcu_sched
17 8 root 20 0 0 0 0 S 0.0 0.0 0:00.00 rcu_bh
18 9 root rt 0 0 0 0 S 0.0 0.0 0:00.00 migration/0
19 10 root rt 0 0 0 0 S 0.0 0.0 0:04.09 watchdog/0

When your attack is complete it will move to Completed Attacks.

Step 3 - Halting a CPU resource attack using the Gremlin App

You can stop a Gremlin Attack at anytime using the Gremlin App. Navigate to Gremlin Attacks and click on the Halt button.

Conclusion

You've installed Gremlin on a Microsoft Azure server running Ubuntu 16.04 and validated that Gremlin works by running the Hello World of Chaos Engineering, the CPU Resource attack. You now possess tools that make it possible for you to explore additional Gremlin Attacks including attacks that impact State and Network.

Gremlin's Developer Guide is a great resource and reference for using Gremlin to do Chaos Engineering. You can also explore the Gremlin Blog for more information on how to use Chaos Engineering with your application infrastructure.

Related

Avoid downtime. Use Gremlin to turn failure into resilience.

Gremlin empowers you to proactively root out failure before it causes downtime. See how you can harness chaos to build resilient systems by requesting a demo of Gremlin.

Get started