How Do You Troubleshoot Nginx Not Being Removed from Ubuntu Linux Like It Should?

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Problem scenario
You want to remove Nginx from an Ubuntu server.  You run this: sudo apt-get remove nginx

But you receive this error:
“
Reading package lists… Done
Building dependency tree
Reading state information… Done
You might want to run ‘apt-get -f install’ to correct these:
The following packages have unmet dependencies:
 nginx-dbg : Depends: nginx (= 1.12.1-1~xenial)
E: Unmet dependencies.

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How Do You Eliminate Highlighting of Text in MS Word 2016?

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Problem scenario
Some text in MS Word 2016 is highlighted with a color as part of its formatting.  No matter what you do (including highlighting it and clicking “No color”) the text remains highlighted.   What should you do?

Solution
Highlight the text (with either the mouse or by holding shift and pressing an arrow key) then press Ctrl and the Spacebar (hold control and tap the spacebar). 

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How Do You Get around the Message “AUTHENTICATING FOR org.freedesktop.systemd1.manage-units”?

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Problem scenario
You are running a yum command or running a script on a RHEL server.  You get this prompt:

“==== AUTHENTICATING FOR org.freedesktop.systemd1.manage-units ===
Authentication is required to manage system services or units.
Authenticating as: Cloud User (ec2-user)
Password:
“

What do you do to troubleshoot this prompt as no password seems to work?

Solution
Cancel out of the prompt. 

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How Do You Deploy Nginx to a Docker Container on an AWS Linux Server?

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Problem scenario
You installed Docker (on either Ubuntu or RedHat, see the links if you actually need help with that).  You do not want to create a Docker network on your server. How do you create a simple Docker container with Nginx without creating a user-defined network?

Solution
#1  Run these two commands:
docker pull nginx
docker run –name docker-nginx -p 80:80 nginx

# If the command hangs,

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How Do You Troubleshoot the Docker Error “User specified IP address is supported on user defined networks only”?

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Problem scenario
When using a “docker run” command you get this error: “Error response from daemon: User specified IP address is supported on user defined networks only.”  What do you do to create a user-defined network?

Solution
#1  From the Linux server (the Docker host), run this command:  ip addr show

#2  Look at the results for eth0. 

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How Do You Choose the Right Spell When Using Conjure-Up and The “Enter” Key Does Not Work?

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Problem scenario
The conjure-up menu is not working.  You run a command like “conjure-up kubernetes” and get to a prompt/screen with an orange banner at the top.  The “Tab” key works.  But “Enter” only works on the “Quit” button.  There is no error message.  How do you proceed with this conjure-up menu prompt  (e.g., to deploy Kubernetes) when the only option that works is “Quit”?

Solution
Expand your Putty session so the GUI is bigger on your screen (wider and longer).  

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How Do You Generate a Load for Your Nginx or Apache Web Server?

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Problem scenario
You set up a load balancing mechanism for your Nginx or Apache web server.  You want to test it and set up an artificial load of traffic.  You want to generate a significant amount of traffic to test the HTTP load balancing mechanism.  How do you do this?

Solution
Here are three scripts that can, by themselves, download a web page 100 times when they execute. 

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How Do You Install the Zabbix Client on an Ubuntu AWS Instance?

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Problem scenario
You are running Ubuntu Linux in AWS.  You want to monitor it with your Zabbix server.  (To set up a Zabbix server in AWS, see this posting.)  How do you install the Zabbix client on an Ubuntu server?

Solution
Section 1
Make sure your AWS Security group allows for inbound connections from the internal IP address of the Zabbix server on any TCP port. 

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How Can You Learn about Kubernetes in One Hour?

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Problem scenario
You need to learn more about Kubernetes but do not know where to start.  You have roughly one hour to try to know much more about Kubernetes.  What should you do?

Solution
For an introduction to Kubernetes, see these two articles from Linux.com and TechTarget.

This DigitalOcean article is a little out of date (as of 9/18/17),

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How Do You Install Zabbix Server on RHEL 7.x Running in AWS?

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Problem scenario
You have a RedHat Linux server with only 1 vCPU and 1 GB of RAM.  You want to install Zabbix Server to monitor other servers.  How do you deploy Zabbix server to an AWS instance of RHEL?

Solution
1. Install the LAMP stack components by running this command:
sudo yum -y install php httpd mariadb-server

2.  Install essential Zabbix components with these four commands:
sudo rpm –import http://repo.zabbix.com/RPM-GPG-KEY-ZABBIX

sudo rpm -Uv 

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