Workshop Exercise - Trash the Instance

Table of Contents

Optional Exercise

This is an optional exercise. It is not required to successfully complete the workshop, but it will help demonstrate the effectiveness of rolling back a RHEL upgrade. Review the objectives listed in the next section to decide if you want to do this exercise or if you would rather skip ahead to the next exercise:



Have you ever wanted to try doing rm -rf /* on a RHEL host just to see what happens? Or maybe you have accidentally done an equally destructive recursive command and already know the consequences. In this exercise, we are going to intentionally mess up one of our pet app servers to demonstrate how rolling back can save the day.

Let’s get started!

Step 1 - Select a Pet App Server

In the next exercise, we will be rolling back the RHEL upgrade on one of our servers.

Step 2 - Choose your Poison

The rm -rf /* command appears frequently in the urban folklore about Unix disasters. The command recursively and forcibly tries to delete every directory and file on a system. When it is run with root privileges, this command will quickly break everything on your pet app server and render it unable to reboot ever again. However, there are much less spectacular ways to mess things up.

Mess up your app server by choosing one of the following suggestions or dream up your own.

Delete everything

Uninstall glibc

Break the application

Wipe the boot record

Fill up your disk

Set off a fork bomb


Congratulations, you have trashed one of your app servers. Wasn’t that fun?

In the next exercise, you will untrash it by rolling back.


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