A Technical I.T./DevOps Blog
Problem scenario
You are using Linux and, you get an error like "write failed" or "quota exceeded." What should you do?
Possible Solution #1
Delete files. Has a runaway program created too many files recently?
Possible Solution #2
You may want to run a quotacheck command because the quota statistics have not been updated.
Problem scenario
You have heard "kube C.T.L." and "kube-cut-el". How should you pronouce kubectl?
Answer
We recommend "kube C.T.L." Source: https://youglish.com/pronounce/kubectl/english?
Problem scenario
You bought new weightlifting shoes. They seem to tight. They are not comfortable. What should you do?
Possible Solution #1
If only one shoe feels too tight, can you see if the tongue is double-up or folded on one side? By flattening it or unravelling it, that may help.
Possible Solution #2
Can you make the velcro strap connect without as much force and tightness?
Possible Solution #3
Loosening the strap(s) or re-tying your shoes in a looser way may help. If it is the first time you have worn weightlifting shoes, there is a good chance they are the right size. Sometimes you may need to buy a bigger size. We think you should try finding a balance between support and comfort. You may need to wear them for a couple weeks to realize that that is how they are supposed to feel.
Possible Solution #4
You could try a two-strap shoe which can distribute the support better in a more contoured way.
See this article for information about why weightlifting shoes are advisable: What Is The Most Important Equipment a Weightlifter Can Own?
Problem scenario
A head lamp bulb needs to be replaced on a car. How difficult is it?
Answer
It is usually fairly easy and does not require tools. Changing blinkers (turn signal bulbs) and headlights is often straight-forward. The bulbs for headlights are smaller than you would think; normally they are much smaller than a typical household lightbulb. (You may think the bulb was not the right one as it seems too small to be compatible with your car. This is normal if you have not changed automobile headlight bulbs before.)
Problem scenario
You have a VIVO sit-stand desk. It says "Er3" on the display. How do you fix this?
Solution
Problem scenario
You want to remove a car stereo. Can something go wrong if so what should you look out for?
Solution
Yes. The airbags could be triggered. The car alarm could go off. Some anti-theft devices sound an alarm if the car stereo is tampered with.
You do not want the airbags to potentially inflate suddenly causing injury to you. They may have a capacitor or way of inflating without the car battery; be careful. The Supplemental Restraint System (which controls and includes airbags), aka SRS, should be disabled before working near the SRS components or wiring (per page 12-23 of the Haynes Repair Manual for the Toyota Corolla and Geo/Chevrolet Prizm 1993 thru 2002). For a Geo Prizm or Toyota Corolla 1993 through 2002, you can disconnect the battery for two minutes and put the key in and turn to "LOCK" to disable the airbag. Other makes and models of vehicles may have different methods for disabling the airbags.
The car alarm may have its own battery. If you disconnect the main battery and something is tampered with, the car alarm could start going off.
Screws could fall into the chassis or the area behind the stereo. (Sometimes there are screws if there is a mounting bracket. This can be common in smaller cars.)
You may want to buy a battery-powered headlamp (as the car battery may be unplugged or there may be insufficient light in the areas you need to see).
You will likely need two "keys" (that can come in an automotive radio removal kit). Car radio keys are not that expensive. What could work are two strips of plumber's straps (or Simpson Strong ties) or flathead screw drivers to insert on the left and righthand sides of the radio when you are facing it. This will make the radio release.
To remove the plastic panels inside (to fully access the radio as it may enclose the radio on the perimeter), you may need a flat head screwdriver.
Generally, not that many things go wrong. You can have limited knowledge of cars, and it will not be that difficult. You want to be careful of the things mentioned above (and possibly other things if your car has customization).
Problem scenario
From a PowerShell prompt, you run a "bcdboot" command, but you see the message "Failure when attempting to copy boot files".
Solution
1. Open PowerShell as an Administrator
2. Run the command again.
It is 15 questions and the answers are available. Click here for the Security Quiz.
1. Most security vulnerabilities are from new or previously unknown problems. True or False?
2. What is one of the protocols IPsec uses to secure IP layer communications?
_________________________________________
3. What is defense in depth (or DiD)?
a. A type of highly-secure cryptography for data at rest.
b. A type of highly-secure cryptography for data in transit.
c. Both of the above.
d. The implementation of a combination of security measures that may be disparate and redundant for achieving security from a pragmatic perspective.
e. A certified protocol recognized by a third party auditing company.
f. None of the above.
Choose the best answer.
4. What does ISMS stand for? ____________________
5. How long does it take for a security breach to be detected usually?
a. Within 60 seconds
b. Within one day
c. Within one week
d. More than 180 days
6. Who usually finds a security breach?
a. The hacker tells the enterprise about what he/she did (e.g., for ransom).
b. The company's internal auditing/security team of professionals.
c. A third party hired by the company that had the breach.
d. The U.S. government.
e. The company's internal auditing/security monitoring tools.
Choose the best answer.
7. What is spear phishing?
a. Phishing against random people.
b. Phishing where the malicious actor knows the target.
c. Phishing against large numbers of people who are part of businesses.
d. Phishing for consumer credit cards.
e. Phishing where the emails fraudulently look like they are from a trusted source.
8. How does SSH work in detail?
_______________________________________________________
9. What does DSA stand for?
a. Defense Shamir Adleman
b. Delay Shamir Adelman
c. Digital Signature Algorithm
d. Direct Symmetric Algorithm
e. None of the above
10. What does the file named "secure" normally have in Red Hat distributions? (It could be found with this command "sudo find / -name secure -type f".) Choose the best answer.
a. Login and access messages.
b. Configuration settings related to Kerberos, Active Directory, Novel, OpenLDAP, NIS, etc.
c. Server-wide configuration settings related to SSH
d. None of the above
11. What is smishing?
________________________
12. What is vishing?
________________________
13. It is acceptable to run OS shell commands from Node.js programs. True or False?
14. What packages are more likely to be updated, Python or Ruby?
15. Secure random number generation (e.g., for computations related to cryptographic keys) is preferably performed with seeding a number via which of the following? Choose the best answer.
a) The Mod or modulo arithmetical function
b) A sequence of unique numbers fixed in the code
c) The system clock
d) The quantified duration between keystrokes
e) All of the above
f) None of the above
For the answers to this quiz, click here.
1. Most security vulnerabilities are from new or previously unknown problems.
True
False
Answer: False. Source page 1 of this PDF.
2. What is one of the protocols IPsec uses to secure IP layer communications?
_________________________________________
Answer: Either AH (Authentication Header) or ESP (Encapsulating Security Payload). Source is juniper.net.
3. What is defense in depth (or DiD)?
a. A type of highly-secure cryptography for data at rest.
b. A type of highly-secure cryptography for data in transit.
c. Both of the above.
d. The implementation of a combination of security measures that may be disparate and redundant for achieving security from a pragmatic perspective.
e. A certified protocol recognized by a third party auditing company.
f. None of the above.
Choose the best answer.
Answer: D. Source: https://www.forcepoint.com/cyber-edu/defense-depth
4. What does ISMS stand for?
Answer: Information Security Management System. ISO 27001 specifies ISMS formally. Source: https://www.iso27001security.com/html/27001.html
5. How long does it take for a security breach to be detected usually?
a. Within 60 seconds
b. Within one day
c. Within one week
d. More than 180 days
Answer: D. Source: https://dev.to/shostarsson/what-is-the-owasp-why-you-should-rely-on-it-1akg
6. Who usually finds a security breach?
a. The hacker tells the enterprise about what he/she did (e.g., for ransom).
b. The company's internal auditing/security team of professionals.
c. A third party hired by the company that had the breach.
d. The U.S. government.
e. The company's internal auditing/security monitoring tools.
Choose the best answer.
Answer: C. Source: https://dev.to/shostarsson/what-is-the-owasp-why-you-should-rely-on-it-1akg
7. What is spear phishing?
a. Phishing against random people.
b. Phishing where the malicious actor knows the target.
c. Phishing against large numbers of people who are part of businesses.
d. Phishing for consumer credit cards.
e. Phishing where the emails fraudulently look like they are from a trusted source.
Answer: E. Source: https://www.dictionary.com/browse/spear-phish
8. How does SSH work in detail?
Here is one possible answer.
9. What does DSA stand for?
a. Defense Shamir Adleman
b. Delay Shamir Adelman
c. Digital Signature Algorithm
d. Direct Symmetric Algorithm
e. None of the above
Answer: C. Source: Page 648 of RHCSA/RHCE Linux Certification Study Guide Sixth Edition by Jang (McGrawHill).
10. What does the file named "secure" normally have in Red Hat distributions? (It could be found with this command "sudo find / -name secure -type f".) Choose the best answer.
a. Login and access messages.
b. Configuration settings related to Kerberos, Active Directory, Novel, OpenLDAP, NIS, etc.
c. Server-wide configuration settings related to SSH
d. None of the above
Answer: A
Source: It is a log file that lists the login and access messages according to page 552 of RHCSA/RHCE Linux Certification Study Guide Sixth Edition by Jang (McGrawHill)
11. What is smishing?
________________________
Answer: SMS phishing. This is the act of sending to cell phones a text message in an attempt to get sensitive information.
Source: https://www.dictionary.com/browse/smish
12. What is vishing?
________________________
Answer: Voice phishing. This is the act of social engineering. You get a phone call and the person is trying to get sensitive information.
Source: https://www.dictionary.com/browse/vish
13. It is acceptable to run OS shell commands from Node.js programs.
True
False
Answer: False. Page 76 of Node.js Security by Liran Tal.
14. What packages are more likely to be updated, Python or Ruby?
Answer: Python. Source: https://www.cpomagazine.com/cyber-security/open-source-security-flaws-exist-in-70-of-applications-80-of-libraries-are-never-updated/
15. Secure random number generation (e.g., for computations related to cryptographic keys) is preferably performed with seeding a number via which of the following? Choose the best answer.
a) The Mod or modulo arithmetical function
b) A sequence of unique numbers fixed in the code
c) The system clock
d) The quantified duration between keystrokes
e) All of the above
f) None of the above
Answer: D. Source: https://www.geeksforgeeks.org/random-vs-secure-random-numbers-java/