How Do You Troubleshoot an Email when the Sender’s Spam Score May Be Bad or Good?

Problem scenario
The email sender may have a low spam score. What should you do to troubleshoot it?

Solution
Do other people get the sender's emails? If so, has it ever worked? If not, check the destination email address. Can the destination email address send an email to the first sender with the problem? You could then reply. Maybe you accidentally typed in the wrong email address.

If you think a "Domain Name System Block List" is affecting you, see this: https://www.spamhaus.org/faq/section/DNSBL%20Usage

To address the spam score issue (which may take days), see these links:

https://www.hihello.me/blog/why-is-my-email-going-to-spam-tips-to-lower-spam-score
https://captainverify.com/blog/improve-spam-score-emails.html
https://www.copernica.com/en/documentation/some-tips-to-lower-your-email-spam-score
https://moz.com/community/q/topic/61742/how-to-reduce-the-spam-score-of-the-website

Is It Valuable to Reflect on the Way a Solution Was Found?

Problem scenario
You are not sure if you should look at how a solution was found. Is it worthwhile to do this?

Answer
Yes. Gottfried Wilhelm Leibnitz said "Nothing is more important than to see the sources of invention which are, in my opinion, more interesting than the inventions themselves." (Page 123 of How to Solve It by Polya.)

Some people are so afflicted with Type A personality, that they need to realize the benefits of leisure. Jacques Ellul in Propaganda: The Formation of Men's Attitudes said it was useful to reflect to avoid the effects of propaganda. Abraham Lincoln said that all learning comes from reflection.

Sometimes Animals Help Members of Different Species

Sometimes animals help humans or distressed animals of different species. Here is a video demonstrating anthropomorphic and compassionate qualities:

Here is a video with a similar theme:

This video shows animals helping a different species of animal:

Birds can work cooperatively with honey badgers to consume honey.

How Do You Troubleshoot Not Having Enough IP Addresses?

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. You may need an extra IP address (besides one per node) to allow an endpoint to become available. Just as in programming with a swap of two variables, a third, temporary variable is needed. One extra IP address may be necessary for an operation that you are performing.

There may be a file or setting (e.g., in DHCP on a router) to allocate more IP addresses. Can you decrease the lease time of DHCP to reallocate an IP address more quickly? If you cannot simply change a file or a setting, subnets may need to be reconfigured. You may need to lease a public IP address. If you were doing maintenance, some endpoints may still be using IP addresses when you do not realize it.

How Do You Troubleshoot “Expected x selector labels” with Kubernetes?

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. Was one line commented out of one file? Could you have placed the stanza in an incorrect location in the YAML file?

Search the YAML file for "env" and "envFrom". Could the user running the command have fewer permissions than normal? Could some files be missing where the "kubectl" command was run from?

To learn more, see these postings:
https://medium.com/@zwhitchcox/matchlabels-labels-and-selectors-explained-in-detail-for-beginners-d421bdd05362
https://kubernetes.io/docs/concepts/overview/working-with-objects/labels/

If you are using OpenShift, or you want more information in general, this RedHat posting could help you: https://learn.redhat.com/t5/DO280-Red-Hat-OpenShift/Labels-and-Selectors/td-p/38276

MOAB: The Mother of All Breaches Happened on January 23rd 2024

January 23rd, 2024 is a day that will live in infamy. 26 billion records were stolen. To learn more, see these external websites:

https://nypost.com/2024/01/23/lifestyle/extremely-dangerous-leak-reveals-26-billion-account-records-stolen-from-twitter-linkedin-more-mother-of-all-breaches/

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

https://www.forbes.com/sites/daveywinder/2024/01/23/massive-26-billion-record-leak-dropbox-linkedin-twitterx-all-named/?sh=4a079d33ab58

Kubernetes Quiz 2

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. numoffailures
e. numfailures

2. Do custom controllers run inside or outside of the control plane?

a. Inside
b. Outside
c. Potentially either A or B
d. None of the above or unknown.

3. How do you view the API resources you have access to?

a. Use online documentation.
b. Run this command: kubectl api-resources
c. Run this command: kubectl config view
d. Run this command: kubeadm list apis
e. None of the above.

4. Which of the following is true?

a. A properly configured headless service always has a selector.
b. A properly configured headless service never has a selector.
c. A properly configured headless service can have a selector but does not need to.
d. There is no such thing as a properly configured headless service in Kubernetes.

5. What is the way of determining how to connect to a service called? Choose the best answer.

a. Service discovery
b. Path determination
c. Route determination
d. kube-proxy routing
e. Label selecting
f. Protocol selecting

6. In Kubernetes, what is a Headless service?
_______________________________________________

7. What container is essential to Heroku?

a. rkt
b. Podman
c. LXC
d. Dyno
e. None of the above

8. A StatefulSet YAML file is a Deployment YAML file with a PVC.

True
False

9. You can limit the CPU and RAM of a "kind: Job" the same way you do with a "kind: Deployment" or a "kind: Pod"

True
False

10. What is an Alpine image?

a. The most commonly used image in Docker or Kubernetes.
b. An image for Kubernetes pods to listen and perform networking functions.
c. A stripped-down Docker image based on Ubuntu Linux
d. A stripped-down Docker image based on Alpine Linux
e. A stripped-down Docker image based on Red Hat Linux
f. None of the above.

11. Roles in Kubernetes are

a. A type of resource
b. Capable of governing what actions can be taken on Kubernetes resources
c. A and B
d. None of the above

12. What should be plural in Kubernetes YAML files? Choose the best answer.

a. endpoints even when there is only one
b. resources even when there is only one
c. kind even when there is only one
d. All of the above
e. A and B
f. None of the above.

13. What is a job in Kubernetes? Choose the best answer.

a. An action that the scheduler assigns.
b. A resource for a discrete task.
c. A component of a Kubernetes operator.
d. The activity that utilizes a pod's computational resources (such as consuming CPU or RAM).
e. None of the above.

14. In Kubernetes a service does what? Choose the best answer.

a. Exposes a Pod as a TCP socket.
b. The Control Plane component that allocates pods.
c. A component of the controller manager.
d. Utilizes a pod to perform non-completable tasks such as listening -- no networking is involved.
e. None of the above.


To see the answers, click here.

Kubernetes Quiz 2 Answers

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. numoffailures
e. numfailures

Answer: A. backofflimit

2. Do custom controllers run inside or outside of the control plane?

a. Inside
b. Outside
c. Potentially either A or B
d. None of the above or unknown.

Answer: D. It is not clear. For Operators, the custom controllers would normally be outside of the control plane.

This quote shows that custom controllers run outside the control plane:

Kubernetes comes with a set of built-in controllers that run inside the kube-controller-manager.
...

You can find controllers that run outside the control plane, to extend Kubernetes. Or, if you want, you can write a new controller yourself. You can run your own controller as a set of Pods, or externally to Kubernetes. What fits best will depend on what that particular controller does.

https://kubernetes.io/docs/concepts/architecture/controller/

This picture also shows that custom controllers run outside the control plane.

The Controller will normally run outside of the control plane…

https://kubernetes.io/docs/concepts/extend-kubernetes/operator/

Kubernetes' out-of-the-box controllers are located in the control plane. However, it’s not allowed to deploy one’s own custom controllers there.

https://blog.frankel.ch/your-own-kubernetes-controller/1/

3. How do you view the API resources you have access to?

a. Use online documentation.
b. Run this command: kubectl api-resources
c. Run this command: kubectl config view
d. Run this command: kubeadm list apis
e. None of the above.

Answer: B. Source: The results of this command explain more: kubectl api-resources -h
You can also view https://stackoverflow.com/a/55358685

4. Which of the following is true?

a. A properly configured headless service always has a selector.
b. A properly configured headless service never has a selector.
c. A properly configured headless service can have a selector but does not need to.
d. There is no such thing as a properly configured headless service in Kubernetes.

Answer: C. Source: https://kubernetes.io/docs/concepts/services-networking/service/#headless-services

5. What is the way of determining how to connect to a service called? Choose the best answer.

a. Service discovery
b. Path determination
c. Route determination
d. kube-proxy routing
e. Label selecting
f. Protocol selecting

Answer: A

Service discovery is the actual process of figuring out how to connect to a service.

https://platform9.com/blog/kubernetes-service-discovery-principles-in-practice/

6. In Kubernetes, what is a Headless service?
_______________________________________________

Answer:

Simply put, a Headless service is the same as default ClusterIP service, but lacks load balancing or proxying. Allowing you to connect to a Pod directly.

https://stackoverflow.com/questions/52707840/what-is-a-headless-service-what-does-it-do-accomplish-and-what-are-some-legiti

7. What container is essential to Heroku?

a. rkt
b. Podman
c. LXC
d. Dyno
e. None of the above

Answer: D.

Dynos: the heart of the Heroku platform

https://www.heroku.com/dynos

8. A StatefulSet YAML file is a Deployment YAML file with a PVC.

True
False

Answer: False.

Deployments and ReplicationControllers are meant for stateless usage and are rather lightweight. StatefulSets are used when state has to be persisted.

https://stackoverflow.com/a/41707491

9. You can limit the CPU and RAM of a "kind: Job" the same way you do with a "kind: Deployment" or a "kind: Pod"

True
False

Answer: True.

Here are some examples:
https://docs.prefect.io/orchestration/execution/k8s_job_environment.html#examples

https://toil.readthedocs.io/en/latest/running/cloud/kubernetes.html#option-1-running-the-leader-inside-kubernetes

https://stackoverflow.com/questions/57697294/does-a-completed-kubernetes-pod-still-reserves-the-required-resources/57697957

10. What is an Alpine image?

a. The most commonly used image in Docker or Kubernetes.
b. An image for Kubernetes pods to listen and perform networking functions.
c. A stripped-down Docker image based on Ubuntu Linux
d. A stripped-down Docker image based on Alpine Linux
e. A stripped-down Docker image based on Red Hat Linux
f. None of the above.

Answer: E. The source says it is "[a] minimal Docker image based on Alpine Linux…" (taken from https://hub.docker.com/_/alpine).

11. Roles in Kubernetes are

a. A type of resource
b. Capable of governing what actions can be taken on Kubernetes resources
c. A and B
d. None of the above

Answer: C. Source: Page 358 of Kubernetes in Action.

12. What should be plural in Kubernetes YAML files? Choose the best answer.

a. endpoints even when there is only one
b. resources even when there is only one
c. kind even when there is only one
d. All of the above
e. A and B
f. None of the above.

Answer: E.
The source of A is Kubernetes.io. The source of B is page 358 of Kubernetes in Action.

13. What is a job in Kubernetes? Choose the best answer.

a. An action that the scheduler assigns.
b. A resource for a discrete task.
c. A component of a Kubernetes operator.
d. The activity that utilizes a pod's computational resources (such as consuming CPU or RAM).
e. None of the above.

Answer: B. Source is page 112 of Kubernetes in Action.

14. In Kubernetes a service does what? Choose the best answer.

a. Exposes a Pod as a TCP socket.
b. The Control Plane component that allocates pods.
c. A component of the controller manager.
d. Utilizes a pod to perform non-completable tasks such as listening -- no networking is involved.
e. None of the above.

Answer: A. Source: Inside cover of Kubernetes in Action.

See also the following:
A Kubernetes service can be described as "[a]n abstract way to expose an application running on a set of Pods as a network service." (This was taken from https://kubernetes.io/docs/concepts/services-networking/service/.) In computing, to abstract can mean to hide an implementation behind a facade (per page 21 of Designing Data-Intensive Applications by Kleppman).

A Kubernetes service can be described as "…a logical abstraction for a deployed group of pods in a cluster." (This was taken from VMware's website.)

Kubernetes services include ClusterIP, NodePort, LoadBalancer, ExtneralName (taken from VMware's website).

Streamlining Success: Tech-Related Outsourcing Tips for Small Business Owners

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.

Prioritize Communication When Outsourcing

Effective communication with hired tech professionals as a small business owner is key to achieving desired outcomes. When collaborating with graphic or web designers on design ideas, conveying precise feedback is essential. Utilizing a free PDF editor tool can streamline this process, particularly when dealing with large PDF files abundant in images. These tools enable the addition of text, sticky notes, highlights, and drawings directly onto the PDF, simplifying the specification of suggestions or changes without resorting to lengthy emails.  PDF editors can enhance communication and streamline feedback becomes an invaluable asset in ensuring clarity and efficiency in the creative process.

Leverage Data Analytics for Business Improvement

Understanding data can provide invaluable insights into customer behavior and business processes. But data analysis is complex and time consuming.

You might benefit from outsourcing this task to specialists in process mining, which employs algorithms to analyze your business workflow. Process mining can illuminate new avenues for operational efficiencies, providing a holistic improvement to your workflow and more. Consider this option for a tailored approach to data-driven business optimization if you're seeking a way to derive actionable insights from your data.

Unveil Visual Brilliance Through Graphic Design

Visual elements like logos, banners, and marketing collateral are crucial for creating a strong brand identity. Instead of spending countless hours trying to master graphic design software, outsourcing this task to a professional can yield high-quality results.

For instance, platforms that connect business owners with freelance graphic designers can quickly match you with a skilled individual capable of bringing your visual ideas to life.

Generate Captivating Content

Quality content is the cornerstone of any successful digital marketing strategy. Outsourcing to skilled writers can help in generating articles, social media updates, and email newsletters that resonate with your target audience. Tools like content management systems make the coordination between you and your outsourced writers seamless.

Elevate Your Digital Marketing Strategies

Hiring marketing professionals can be a game-changer for your small business. Experienced marketers bring a deep understanding of market trends, consumer behavior, and effective advertising channels. They can craft tailored campaigns that resonate with your target audience, optimize your budget allocation, and provide valuable insights through analytics.

Hire Out (or Learn) Coding

Hiring a skilled coder to assist with your website, software, or app development is a crucial step toward success in today's digital landscape. Their expertise can streamline the development process, ensuring a robust and user-friendly product.

Additionally, online resources are invaluable for project owners looking to grasp the basics of a successful web-based project. These resources offer insights into coding languages, design principles, and project management techniques, empowering you to communicate effectively with your coder and actively participate in the development process. 

Secure Your Online Assets Through Cybersecurity

In an era of increasing cyber threats, maintaining robust cybersecurity is essential. Outsourcing cybersecurity management to a qualified expert means that you benefit from the latest in security technology. Firewall management services, intrusion detection systems, and other technologies can help protect your business against unauthorized access and data breaches.

Optimize Financial Management

Keeping track of financial data, from invoicing to taxation, is a critical but often tedious part of running a small business. Financial experts can efficiently manage your financial records with accounting software to ensure you remain compliant and make well-informed financial decisions.

Enhance Outreach Through Email Marketing

Email campaigns are still an effective way to engage your customer base. Specialized software can automate the process of sending out emails, tracking open rates, and analyzing engagement. Outsourcing this aspect to a seasoned email marketer can optimize this channel for the best possible returns.

The Bottom Line

Outsourcing specialized tech-related tasks is an intelligent approach for small business owners looking to streamline their operations for maximum efficiency and growth. Delegating your graphic design, data analysis, digital marketing, and other activities to seasoned professionals gives you the margin to concentrate on your business's core objectives.

Start allocating your tasks strategically to free up valuable time and resources and pave the way for success in an increasingly competitive market. Your company will be better equipped to flourish for years to come.