A Technical I.T./DevOps Blog
Problem scenario
You want to use an Azure pipeline. You want it to perform a build. What should you do?
Solution
Prerequisites
i. You must have a supported code versioning system with certain files. As of 10/7/19 the options are Azure Repos Git, Bitbucket Cloud, GitHub, GitHub Enterprise Server, other Git repositories or Subversion. If you follow steps 1 through 4 of How Do You Build a Java Program with Maven?
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Continue reading “How Do You Create a Build Pipeline in Azure?”
Question
What is a Secret in Kubernetes?
Answer
It is a ConfigMap with sensitive data that is encoded in Base64 text. What is a ConfigMap? It is a .yaml with a special format. There is always a “data:” section that is part of the YAML definition of a ConfigMap. The key-value pairs in the “data” section will have keys that appear in regular text;
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Question
What is a ConfigMap in Kubernetes?
Answer
A ConfigMap is a mapping of configuration originally in YAML format that resides in etcd (partially taken from this external posting). A .yaml file will define the version of the Kubernetes API (e.g., version 1), data, and the “kind:” key will be set to “ConfigMap”.
The content of the ConfigMap is consumed by an application in Kubernetes.
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Question
What is an HPA in Kubernetes?
Answer
HPA stands for HorizontalPodAutoscaler. It is a concept and resource that allows clusters to scale out upon a certain condition being met. HPA can support a pod to scale based on certain amounts of CPU utilization. It natively supports granular CPU requests down to a single millicore. A .yaml file in Kubernetes has the key “kind”;
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Question
What is a deployment in Kubernetes?
Answer
A deployment is a resource that is designed for “deploying applications and updating them declaratively” (page 261 of Kubernetes in Action by Luksa). You may hear the phrase “Deployment controller.” This is a reference to a component of the Controller Manager in the Kubernetes Control Plane (page 262 of Kubernetes in Action by Luksa).
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Question
What is a difference between a readinessprobe and a livenessprobe besides how the corresponding fields are used in defining a Pod using YAML?
Answer
At most a failed liveness probe will result in the restarting of a container. At most a failed readiness probe will result in the removing a pod from the endpoint of a service (page 150 of Kubernetes in Action).
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Problem scenario
Kubernetes can use YAML files for configuration. The book Kubernetes in Action by Luksa refers to these files as manifests (pages 148), YAML manifests (page 155) or “pod manifests” (page 451). The Kubernetes website refers to this YAML file as “the PodSpec” here. Pod templates are defined inside these .yaml files (as a subset of the file itself). How do you use these YAML files?
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Continue reading “How Do You Use a YAML File or a YAML Manifest in Kubernetes?”
Question
What is the difference between these three two-word terms “pod label,” “label selector,” and “pod selector”?
Answer
This answer provides details on what these are and provides some information on how they are different.
pod label: It is an inherent attribute of the pod. It can be changed via a command like this: kubectl label pod new-podlabel version=5.5 These statements were based on Assistanz.com.
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Problem scenario
You want to use infrastructure as a code with Terraform and GCP. How do you use a .tf file to create a virtual machine in Google Cloud Platform?
Solution
Prerequisite
This assumes you have installed Terraform. If you need assistance with this, see this posting.
Procedures
1.
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Continue reading “How Do You Use Terraform to Create a Server in GCP?”
Updated 8/1/21
Problem scenario
An Ansible playbook appears to run with no errors or explicit failures. But the playbook is not working as you expect. There is no message indicating what could be wrong. What should you do to troubleshoot it so the intended effect(s) will happen?
Tips and Possible Solutions in Nearly Random Order
1. When you run the ansible-playbook command,
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