A Technical I.T./DevOps Blog
Problem scenario
One of the below three situations describes your problem:
#1 You insert a USB stick and nothing happens. You know the USB sticks work with other computers.
OR
#2 You insert a USB stick and nothing happens for a while. There is a long delay. You know the USB sticks work fine with other computers.
OR
#3
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Problem scenario
You are using Ansible’s find module. You want it to find the destination of a symbolic link. When you run the playbook you have a way of finding what the find module returns. It is saying something about “directory was skipped as it does not seem to be a valid directory or it cannot be accessed.” What should you do?
Solution
Use the stat module.
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Problem Scenario
You want to install the Kerberos KDC server on a Red Hat derivative of Linux. You want to test it out with a second Red Hat distribution of Linux server as a client of the Kerberos centralized authentication server. What do you do?
Solution
Prerequisites
Ensure the Kerberos authentication server can receive inbound connections over ports 88, 464,
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Problem scenario
You want to install Foreman on a RHEL server. What should you do?
Solution
Warning
If you install this on a server that is already a Puppet master server, your site.pp file will be overwritten.
Procedures
Tips: With EC-2 instances, you can usually skip to step #3.
1. Modify /etc/hostname to be the FQDN of your server (the result of a hostname -f command).
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Continue reading “How Do You Install Foreman on a RHEL Server?”
Problem scenario
You want to write a Python program with a bound method. What should you do?
Solution
This program uses a bound method. The method funtest() is bound to objects that are members of the class “widgetfactory”. You cannot use the method without it being bound to this class. (If you uncomment out the last line, you’ll see it is a bound method and not an unbound method;
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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?”