Where Can You Find a Complete List of the Reserved Words for Declarative Pipeline Syntax?

Problem scenario
You want to create a Jenksinfile for a pipeline. Where can you find a complete list of the reserved words for Declarative pipeline syntax?

Answer
This external page has something close. It does not go into into how “sh” works. Using “sh” you can run Linux commands. There are “bat” and “powershell” options too. Here is an example (taken from Jenkins’ website) :

pipeline {
agent any
stages {
stage(‘Build’) {
steps {
sh ‘echo “Hello World”‘
sh ”’
echo “Multiline shell steps works too”
ls -lah
”’
}
}
}
}  » Read more..

What is an HPA in Kubernetes?

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 Kubneretes has the key “kind”;

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How Do You Use the Docker Pipeline Plugin with Jenkins?

Problem scenario
You want to use the Docker Pipline (with the Jenkins ID of “docker-workflow”). What do you do?

Solution
Prerequisites
Jenkins needs to be installed. If you need assistance, see this posting if you are using a CentOS/RHEL/Fedora server; if you want to install Jenkins on a Debian/Ubuntu server, see this posting.

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What is Operational Readiness in I.T.?

Question
How would a DevOps engineer define operational readiness or what is operational readiness in I.T.?

Answer
“All things are ready, if our mind be so.” –William Shakespeare

While some people would say it is more of a state*, others may say it is more of a journey**. Operational readiness is having sufficient staff and automation to maintain the minimum level of service that the business requires for a given product or service.

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What is an Ingress Resource in Kubernetes?

Question
What is an Ingress resource in Kubernetes?

Answer
It is a Kubernetes technique of exposing services via an individual IP address (page 135 of Kubernetes in Action by Luksa). In TCP/IP networking, the Ingress port allows inbound traffic to route somewhere. Kubernetes supports other IP address to service mapping methods (e.g., NodePort or LoadBalancer). NodePort operates on layer 4 of the OSI seven-layer model (according to this posting).

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How Do You Install Splunk in a Docker Container?

Problem scenario
You want to run Splunk from a Docker container. What do you do?

Solution
Prerequisites
Install Docker. If you need assistance, see this posting.

Procedures
1. Run this command: docker pull splunk/splunk:latest

2. Run this command, but replace “simpleword” with the password that you want the administrator account for the web UI to have:

docker run -d -p 8000:8000 -e ‘SPLUNK_START_ARGS=–accept-license’ -e ‘SPLUNK_PASSWORD=simpleword’ splunk/splunk:latest

3.

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In Python Are Dictionaries Much Slower in Performance Compared to Lists or Tuples?

Problem scenario
You want to know how dictionaries perform as iterables in Python. In Python for printing the values of every key-value pair in a dictionary, is it faster or slower than printing every item in a list? How does it compare to a tuple?

Solution
For this example we use integer keys in the dictionary. Keys can be strings or other objects.

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What is a Deployment in Kubernetes?

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.” As far as we know this is a reference to the process that runs in the Kubernetes Control Plane (page 262 of Kubernetes in Action by Luksa).

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How Do You Install the Angular CLI on a Linux Server?

Problem scenario
You want to test out the Angular CLI on a Linux server. What should you do?

Solution

Prerequisite
Install node and npm. If you nsee assistance, see this posting How Do You Install node and npm on Any Distribution of Linux Server?.

Procedure
Run this command: sudo npm install -g @angular/cli

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What is Telemetry in I.T.?

Question
In the context of computers, what is telemetry?

Answer
Telemetry in I.T. is the logged system data transmitted from other servers.

A more detailed definition of telemetry is the utilization of a centralized system to automatically ingest log data from other sources to enable one or more of the following: redundant storage of critical log data, monitoring, data visualization, anomaly detection,

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