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Measure Raspberry Pi temperature using Telegraf, Influxdb, Grafana on k3s

Measure Raspberry Pi temperature using Telegraf, Influxdb, Grafana on k3s.

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January 1, 2020

k3s cluster with Raspberry-Pi, Traefik

Walk through on setting up K3S cluster on raspberry pi and traefik ingress with cloudfare.

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December 31, 2019

Permission denied pushing to OpenShift Registry

Permission denied on pushing build images into OpenShift internal registry

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December 18, 2019

Basic Authentication in Go with Gin

Basic user authentication with gin web framework in Golang

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December 16, 2019

Create and add NFS storage to RHV

Set up NFS shares that will serve as storage domains on a Red Hat Enterprise Linux server. Add a firewall rule to RHEL server. firewall-cmd --permanent --add-service nfs firewall-cmd --permanent --add-service mountd firewall-cmd --reload Create and add group kvm; set the ownership of your exported directories to 36:36, which gives vdsm:kvm ownership; change the director’s permission so that read and write access is granted to the owner.

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November 2, 2019

Configuring couchbase SSL for dynamic certificates in OpenShift

Couchbase SSL Suppose you have followed dynamic creation of java keystores in OpenShift post and wondered how to use similar concepts for couchbase database and a java application. This post will help you. Couchbase setup Here is the couchbase documentation for configuring server-side certificates, we are interested in last few steps since OpenShift will generate key and cert by adding an annotation to the couchbase service.

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August 28, 2019

TektonCD on OpenShift

Recently I came across tektoncd project, The Tekton Pipelines project provides Kubernetes-style resources for declaring CI/CD-style pipelines caught my attention, and I started playing with it. Basic Concepts To create a Tekton pipeline, one does the following: Create custom or install existing reusable Tasks Create a Pipeline and PipelineResources to define your application’s delivery pipeline Create a PipelineRun to instantiate and invoke the pipeline Installing Tekton on OpenShift Log in as a user with cluster-admin privileges.

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August 9, 2019

Go JWT Authentication with Keycloak

I recently worked on a React project with Go backend using Gin web framework. Keycloak was the authentication mechanism for the front end; I also wanted to secure the back end using JSON Web Tokens, which Keycloak provided on every login. JWT verification setup in the Go application was easy. First, copy the RS256 algorithm public key value from Keycloak. Send the token as an Authorization header. axios .get(BACKEND_URL.concat("sampleendpoint"), { headers: { Authorization: this.state.token } }) .then(res => {}); Now Go-backend setup; let’s install the jwt-go, gin-cors libraries:

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July 27, 2019

React App with RedHat SSO or keycloak

This post will show you how to secure a React app using RedHat SSO (upstream Keycloak). In this case, OpenID-connect is my identity provider. Install the official Keycloak js adapter npm i keycloak-js --save Add host and port information to the client; in my case, it’s localhost:9000

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July 25, 2019

Heketi JWT token expired error

Recently I encountered a JWT token expired error on the heketi pod in the OpenShift cluster. [jwt] ERROR 2019/07/16 19:17:14 heketi/middleware/jwt.go:66:middleware.(*HeketiJwtClaims).Valid: exp validation failed: Token is expired by 1h48m59s After a lot of google searches, I synchronized clocks across the pod running heketi and the master nodes, which solved the issue

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July 16, 2019