How Do You Install chattr on Ubuntu?

Problem scenario
You get “command not found” when you try to run “chattr”. What should you do?

Solution
Run this command: sudo apt -y install e2fsprogs

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Where Does The Term Ping Come From?

Question
Ping is a common diagnostic tool in networking technology. It is essentially an echo request to confirm an IP address is up and accessible. Where does the term ping come from?

Answer
The acronym for “packet inter-network groper” seems like it is a backronym for the trademarked table tennis game which involves a lightweight ball being returned in the opposite direction that it was sent.

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How Do You Find Files on a Linux Disk That Are larger than One Gigabyte?

Problem scenario
How do you find files on a Linux server that consume more than one gigabyte of space?

Solution
Run this command: sudo find / -size +1G -type f -print

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Is there a Docker Hub equivalent for OpenShift?

Problem scenario
Docker Hub is a public registry for containers. Does OpenShift support something like this? You know they have the OpenShift Container Registry — but this is private to a given OpenShift instance. Red Hat owns OpenShift. Is there a public registry supported by Red Hat?

Answer
Yes. It is called Quay.io. If you want a brief overview of it,

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How Do You Find the kubectl Version Your Kubernetes Server Is Running?

Problem scenario
You know the kubectl version that is running on your client machine. How do you determine the version that your Kubernetes master node is running?

Solution
From the client machine, run this command: kubectl version | grep Server

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How Do You Create a Customer Managed Key in AWS?

Problem scenario
You want to create a CMK in Amazon web servers. What do you do?

Solution
Use Secrets Manager with Amazon’s Key Management Service.

1. Log into the AWS console.
2. Go to “Key Management Service”
3. Click on “Create key”
4. Enter an “Alias”. Normally you won’t click on the “Advanced options” unless you have a special reason.

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How Do You Extract a File from a .zip File without unzip?

Problem scenario
You have a .zip file, on your Linux server, that you want to uncompress. You do not have unzip installed on your machine. What should you do?

Possible Solution #1
Install unzip. If you are using a Debian/Ubuntu distribution of Linux, run this: sudo apt -y install unzip

Possible Solution #2
You could use WinSCP to download the file to your Windows workstation.

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How Do You Find Where the Python Interpreter Will Look for Modules?

Problem scenario
You want to use custom modules (e.g., .py files that will be called by another Python program). You are trying to figure out which location(s) the Python interpreter will look for such modules. How do you determine the directory where Python will look when it uses the “import” key word?

Solution
Run these three commands (the first is a Bash command and the other two are Python):

python
import sys
print(sys.path)  » Read more..

How Do You Troubleshoot the Python Error “subprocess.CalledProcessError: Command ‘…’ returned non-zero exit status 1”?

Problem scenario
You are automating a Linux infrastructure task with Python using subprocess calls. You get this error “subprocess.CalledProcessError: Command ‘…’ returned non-zero exit status 1”, what should you do?

Solution
Run the Linux command without Python. Then run echo $? to determine the exit code. If you see a 1, that means Python notices this command is not considered to have run successfully.

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What Should The Permissions of the kubectl File Be on a Linux server?

Problem scenario
You copied the kubectl file. You are not sure what the permissions it should have. When you try to execute it, you get “Permission denied”. What should you do?

Solution
We recommend using this (after you change directories to the one that has the kubectl file): sudo chmod 777 kubectl

When you use conjure-up, it makes kubectl have 777 permissions.

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