A Technical I.T./DevOps Blog
Question
You have heard of the term daemon when it refers to a process, service or listener of an OS. Where did this term come from?
Solution
According to page 440 of A Practical Guide to Fedora and RedHat Enterprise Linux by Sobell, the terms daemon, service and server are all interchangeable. Demons are invisible presences like spirits. The term “daemon” is Latin and is pronounced exactly the same as “demon” according to Dictionary.com.
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The Union victory of the Civil War forced the southern states back into the Union under its jurisdiction. On February 1, 1865 President Lincoln signed a resolution permanently outlawing slavery in the U.S. (www.timeanddate.com).
This resolution became the 13th amendment which was ratified later that year after Lincoln’s death (www.timeanddate.com).
A former slave named Richard Wright became a successful businessman in Philadelphia in the 1900s (http://www.americaslibrary.gov/es/pa/es_pa_free_1.html).
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Problem scenario
You want to get inside a Docker container that is running. You are on the Docker host. What should you do?
Solution
1. Run this command: docker ps -a # Find the container ID in the output
2. Run this command but substitute abcd1234 with the container ID found above:
docker exec -it abcd1234 bash
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Continue reading “How Do You Enter a Docker Container That is Currently Running?”
Problem scenario
You try to run a command with sudo and you are prompted for the root user password (not the password for the username who issued the sudo command). You want to be prompted for the user (e.g., jdoe) not root. What should you do?
Solution
Root cause
sudo is not configured properly.
Procedures
1.
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Problem scenario
You want to write a “Hello World” program using Node.js. What do you do?
Solution
Prerequisite
Identify the external IP address of the server (e.g., run “curl icanhazip.com” if you have access to the internet).
Procedures
1. Install node and npm on a Linux server. If you need assistance with this,
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Continue reading “How Do You Write a Hello World Program in Node.js?”
Problem scenario
You want to create a basic “Hello World” web page with Node.js running in a Docker container. How do you do this?
Solution
Prerequisite
Install Docker. If you need assistance, see this posting.
Procedures
1. Create three files in the same directory on a Linux server.
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Problem scenario
You are writing code in Python. You have a list that you want to have a copy of in the form of a tuple. What do you do to convert the content to a different data type?
Solution
Assuming you have a list called “contintlist”, this line would create a tuple with the content of “contintlist”:
cooltuple = tuple(contintlist)
Here is a Python program that generates a list,
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Continue reading “How Do You, in Python, Make a Tuple from a List?”
Problem scenario
You want to create an organization in GitHub.
Solution
1. Log into GitHub.
2. Go here: https://github.com/organizations/new
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Continue reading “How Do You Create an Organization in GitHub?”
Problem scenario
You want to generate 10,000 random numbers in a tuple. That is, you want a tuple with 10,000 numbers. The numbers can be chosen at random. How do you do this?
Solution
Run this program:
import random
coollist = []
for i in range(1000000):
coollist.append(random.randint(1,100000))
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Continue reading “How Do You Generate 10,000 Random Numbers in a List in Python?”
Problem scenario
You want a quick, generic way to install kubeadm on any type of Linux. What should you do?
Solution
Run these commands:
cd /tmp
curl -Lo kubeadm https://storage.googleapis.com/kubernetes-release/release/$(curl -s https://storage.googleapis.com/kubernetes-release/release/stable.txt)/bin/linux/amd64/kubeadm && chmod +x kubeadm
sudo mv kubeadm /usr/bin/
Test it by running this command: kubeadm version
(If you would prefer to use apt commands,
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Continue reading “How Do You Install kubeadm on Any Type of Linux?”