A Technical I.T./DevOps Blog
Problem scenario
You get an error about insufficient IP addresses. You have exhausted a pool of IP addresses but you do not understand why. What could be wrong when you have no spare IP address, or you get a message related to this problem when you do not think that there is a shortage?
Possible Solution
You were doing an upgrade with a “rolling” option such that there was no downtime.
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Continue reading “How Do You Troubleshoot Not Having Enough IP Addresses?”
Problem scenario
You run a kubectl command on a YAML (.yml) file. But you get “Expected X selector labels”. What do you do?
Solution
Go to the “labels” and “matchlabels” sections of corresponding YAML files. Do you see “app:” or “environment:” stanzas? Are these consistently used in your YAML files? This error can happen if the YAML files are inconsistent with their “app:” and “environment:” stanzas.
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Continue reading “How Do You Troubleshoot “Expected x selector labels” with Kubernetes?”
January 23rd, 2024 is a day that will live in infamy. 26 billion records were stolen. To learn more, see these external websites:
https://cybernews.com/security/billions-passwords-credentials-leaked-mother-of-all-breaches/
https://mashable.com/article/mother-of-all-breaches-leak-26-billion-cybersecurity
https://www.techopedia.com/mother-of-all-breaches-everything-you-need-to-know
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Continue reading “MOAB: The Mother of All Breaches Happened on January 23rd 2024”
This is a quiz about containers, Docker, and Kubernetes — but mostly about Kubernetes. You can test yourself before a job interview. You may also want to see this list of Kubernetes books.
1. To set a maximum number of failures threshold, which of the following key words would you use (for a Kubernetes application to try a pod)?
a. backofflimit
b. maxnumretries
c. retriesmax
d.
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This is a quiz about containers, Docker, and Kubernetes — but mostly about Kubernetes. You can test yourself before a job interview. You may also want to see this list of Kubernetes books.
1. To set a maximum number of failures threshold, which of the following key words would you use (for a kubernetes application to try a pod)?
a. backofflimit
b. maxnumretries
c. retriesmax
d.
…
Image via Freepik
In today’s dynamic business environment, small business owners are often tasked with a myriad of responsibilities, juggling various roles to ensure the wheels keep turning. Balancing every aspect of business management can be overwhelming, and there’s an undeniable advantage in delegating specialized tasks to experts.
Doing so not only improves efficiency but also allows you to focus on the core aspects of your business. The following article from bizhelpportal.com explains which tech-related tasks are prime candidates for outsourcing.
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Continue reading “Streamlining Success: Tech-Related Outsourcing Tips for Small Business Owners”
Problem scenario
You are not sure if an email address is associated with spam. Someone make comments on your blog. You are not sure if they are legitimate comments or if it is someone trying to spam a website or create a message that is an advertisement. What should you do to check-in on the email address?
Solution
Try https://cleantalk.org/blacklists/
On cleantalk.org you can search for IP addresses,
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Problem scenario
You have a file that is too big to fit into memory. How can Python read the file?
Possible Solution #1
You can use the “open” method and the “read()” or “readlines()” methods. Avoid using read() because that will read the entire file into memory. The readline() and readlines() methods can be given a byte number as an argument. They will retrieve only a portion of the file.
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Continue reading “How Do You Write a Python Program to Process a Large File?”
Problem Scenario
You run an HDFS command, but you get this message: “ERROR: Hadoop common not found”
What should you do?
Solution
As the hduser or user that runs hdfs, log in. Run echo $HADOOP_HOME
That directory should have a libexec directory with a file called hadoop-config.sh.
Run this: ls -lh $HADOOP_HOME/libexec
One way to create it is this: 1) find a hadoop-config.sh file (e.g.,
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Continue reading “How Do You Troubleshoot “ERROR: Hadoop common not found” when Running Hadoop?”