A Technical I.T./DevOps Blog
Problem scenario
You know .crt and .key files can pair as ssl_certificates and SSL certificate keys respectively. In Nginx, can .pem files replace .crt files? Can .pem files potentially replace .key files? Can a .pem file be a substitute?
Solution
Yes to some extent, for the nginx.conf file, a .pem file can replace a .crt file and potentially a .key file too.
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Continue reading “With Nginx Can a .pem file replace a .crt and/or a .key File?”
Problem scenario
You want to remove the battery from your Nokia flip phone. There is a hinge, and the phone closes as normal like a clamshell. But you need to restart the phone (e.g., and it will not shut off). How do you remove the battery from a Nokia phone?
Solution
While the phone back cover may seem hard to come off,
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Continue reading “How Do You Remove the Battery Cover of a Nokia Cell Phone?”
Problem scenario
You run “docker-compose build” and you get this:
1 error occurred:
* unable to prepare context: unable to evaluate symlinks in Dockerfile path: lstat /home/jane/dockercompose/webapp/Dockerfile: no such file or directory
What should you do?
Solution
Look at your docker-compose.yml file. Look at the “build” stanza. What directory is it referring to? Is a Dockerfile file in that directory?
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Problem scenario
You turn on your laptop and Bluetooth wireless speaker. Your external speaker is not working. What should you do?
Possible Solution #1
Is the Bluetooth device on?
Possible Solution #2
Go to Control Panel -Hardware and Sound -Manage audio devices. Do you see a device that could be the wireless one?
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Continue reading “How Do You Get a Bluetooth Speaker to Work with Your Windows Laptop?”
One of the following apply:
Problem scenario #1
You run this: “sudo systemctl start docker”
But you get this: “Failed to start docker.service: Unit docker.service not found.”
Problem scenario #2
You run this: “sudo systemctl start docker”
But you get this:
“docker.service: Service has no ExecStart=, ExecStop=, or SuccessAction=. Refusing.”
or this:
“Failed to start docker.service: Unit docker.service not found.”
Problem scenario #3
You run this: sudo systemctl enable docker
But you get this: “Failed to enable unit: Unit file docker.service does not exist.”
Solution
Use this posting.
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Continue reading “How Do You Create a docker.service File on a Linux Server?”
Problem scenario
You want modified the /etc/fstab file. You want to reboot, but you are concerned your server won’t work if you accidentally had a typo in the /etc/fstab file. What should you do?
Solution
sudo mount -o remount,rw /dev/path/to /path/to/use
The /path/to/use is the path that you will see on your Linux system.
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Continue reading “How Can You Test Your /etc/fstab File without Rebooting the Linux Server?”
Problem scenario
You are trying to understand some code. You see a variable in Python that represents a list being cast to a set.
You see something like this in a Python program:
example = [1, 1, 2, 2, 3, 3]
new_example = set(example)
You are curious why this would be done.
From the IDE you do (and see) the following:
example = [1, …
Continue reading “Why Would You Assign or Copy a list in Python to be a set?”
Question
What does MoRef mean?
Answer
It is a portmanteau of “Managed Object Reference.” It is a data type that comes up in the context of alerts/alarms in vSphere.
(The answer was adapted from page 152 of PowerCLI Cookbook by Sellers.)
“MoRefs are unique identifiers assigned to objects at the time of their creation.” (Taken from page 202 of PowerCLI Cookbook by Sellers.)
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Question
Does an athletic interest affect your life span?
Answer
Possibly. The relationship could be correlative or causal.
The expected average longevity for male athletes was 56 years for cyclists, 66 years for weightlifters, 75 years for rugby players and 92 years for golfers.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8532055/ …
Continue reading “Does the Sport You Like Determine How Long You Will Live?”
Problem scenario
You want to modify the /etc/sudoers file. What should you do?
Solution
You may want to back it up. Never modify it with vi, vim or gedit. Use “sudo visudo”. Page 433 of A Practical Guide to Fedora and RedHat Enterprise Linux recommends you always use sudo visudo. If you accidentally corrupt the file when modifying /etc/sudoers manually,
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