metadata.labels, selector.matchLabels, template.metadata.labels – Kubernetes Deployments Explained

There are a lot of label and selectors being placed all around deployment yaml files inside Kubernetes deployments and this gets people confused. Let me try to shed some light on this and clear your confusion. Let’s start with an

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VirtualBox Problem on Windows 10 – raw-mode unavailable courtesy of Hyper-V

You may see this message while trying to run VirtualBox on Windows 10: raw-mode unavailable courtesy of Hyper-V. To solve this problem follow these steps: Open the command prompt as an Administrator. Run the command with no argument: bcdedit. You will

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Installing and configuring PACEMAKER as a Cluster Manager – CentOS7

how to install and configure pacemaker

In this post, I will try to document the steps needed to set up and install Pacemaker as a cluster manager on CentOS7. Relate this post to the one that is about DRBD and combine them to get yourself a

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Installing and Configuring DRBD for High Availability – DRBD for Apache Server

DRBD example setup and configuration

DRBD stands for Distributed Replicated Block Device. DRBD is a distributed replicated storage system for the Linux platform which is implemented as a kernel driver. The main configuration file for DRBD is /etc/drbd.conf.   include “drbd.d/global_common.conf”   include “drbd.d/*.res” DRBD configuration

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Clearing the OpenShift log data using the curator pod (OpenShift 3.6)

openshift

In our test OpenShift cluster, we had this space problem with the infra node. See the numbers below. Previously: Filesystem Size Used Avail Use% Mounted on /dev/mapper/rhel-root 50G 2.0G 49G 4% / devtmpfs 7.8G 0 7.8G 0% /dev /dev/sdd2 50G

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SonarQube 6.5 Resetting admin Password on CentOS7

Install pgAdmin on centos7 (GNOME environment) – yum install pgadmin4-desktop-gnome check the config file of sonarqube – /opt/sonarqube/conf/sonar.properties – sonar.jdbc.url=jdbc:postgresql://localhost/sonar – sonar.jdbc.username=sonar – sonar.jdbc.password=Password1 start pgAdmin by simply running “pgadmin4” command OR Applications -> Programming -> pgAdmin 4 Under Quick

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Introduction to Persistent Storage In OpenShift

openshift persistent volumes

Not all the containers in your cluster will be non-persistent or ephemeral. Most of the time you will need persistent containers running all around the place to hold some sort of data. To store the data independent of the lifetime

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Adding Jenkins Slaves (Linux/ CentOS7)

This is a post I have been thinking about writing for some time and I finally had the time to do that. In the beginning, it could be enough to use just a single Jenkins instance (master), but sooner or later

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OpenShift – See the Contents of Your Deployed Jar Inside a Running Pod

openshift

You can follow the steps below to see the contents of your deployed jar archive inside a running pod in your OpenShift cluster: 1- Login to master 2- Browse to namespace/project 3- oc get pods 4- oc rsh {pod_name} 5- cd to

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OpenShift – Simple Bash Script to Periodically Check Node Status

openshift

This is a very basic example bash script that I wrote. Using this script you can check the node status of your OpenShift cluster periodically on your master node. Take it as a basis and expand it to your needs. Bash version: GNU

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