Posts

Kubernetes Cert Manager for Letsencrypt Based Certificates With Nginx Ingress

Cert Manager cert manager stores certificates in kubernetes secret store and we can configure the nginx-ingress to use these certificates. cert-manager.yaml wget https://github.com/jetstack/cert-manager/releases/download/v0.15.1/cert-manager.yaml kubectl apply --validate=false -f cert-manager.yaml cert-manager.crds.yaml wget https://github.com/jetstack/cert-manager/releases/download/v0.15.1/cert-manager.crds.yaml kubectl apply --validate=false -f cert-manager.crds.yaml using the ClusterIssuer allows us to create certificates across all namespaces letsencrypt-issuer.yaml apiVersion: cert-manager.io/v1alpha2 kind: ClusterIssuer metadata: name: letsencrypt-prod spec: acme: # The ACME server URL server: https://acme-v02.api.letsencrypt.org/directory # Email address used for ACME registration email: loeken@internetz.

June 13, 2020 Read

Kubernetes Create Images in Google Container Registry

create a user and a project we ll be using the command line tool pacaur -S google-cloud-sdk create a GCP service account; format of account is email address SA_EMAIL=$(gcloud iam service-accounts --format='value(email)' create k8s-gcr-auth-ro) create the json key file and associate it with the service account and save it in k8s-gcr-auth-ro.json gcloud iam service-accounts keys create k8s-gcr-auth-ro.json --iam-account=$SA_EMAIL get the project id PROJECT=$(gcloud config list core/project --format='value(core.project)') add the IAM policy binding for the defined project and service account

June 12, 2020 Read

Kubernetes Prometheus & Grafana

Kubernetes & Prometheus Prometheus by defaults pulls info from the hosts via an http endpoint by default this is the /metrics endpoint Data exposed on this /metrics endpoint needs to support the prometheus endpoint. Exporter is a standalone tool that gathers data and exposes it on the /metrics endpoint These exporters are also available via docker ( can be used as sidecar containers ) Promotheus Server Data Retrieval Worker ( pulls metrics data) Time Series Database ( stores time series metrics data ) Api ( to access this stored data ) View Data Prometheus Web Ui Grafana Terms Targets: anything monitored Units: a subset of whats monitored

June 11, 2020 Read

Kubernetes Nodejs Postgresql Example With Nginx Ingress

Kubernetes nodejs postgresl example with nginx ingress Download Image Markup this would be an example to create an ingress that points to our internal node service apiVersion: v1 kind: Ingress metadata: name: node-ingress spec: rules: - host: nodeexample.com http: paths: - test: serviceName: node-service servicePort: 1337 Let’s now combine this with our last two node and postgres deployments we wrote and create a new deployment for node/postgresql using the ingress with an internal service vs using the external service for the node app.

June 10, 2020 Read

Kubernetes Namespaces

Kubernetes namespaces Imagine two teams build similar apps running in the same cluster. in order to avoid duplicated names etc and in order to group resources namespaces can be used to logically separate things. You could also use it to separate staging/production You could also use it if you want to run multiple different production environments. Notes: ConfigMap and Secrets can only be used inside a namespace Namespaces can be used to limit access to namespaces Namespaces can be used to limit resources to namespaces ( cpu / mem / storage ) the default namespaces kubectl get namespaces NAME STATUS AGE default Active 5d14h kube-system Active 5d14h kube-public Active 5d14h kube-node-lease Active 5d14h kubernetes-dashboard Active 5d14h manage namespaces via command line kubectl create namespace mynamespace namespace/mynamespace created kubectl get namespaces NAME STATUS AGE default Active 5d14h kube-system Active 5d14h kube-public Active 5d14h kube-node-lease Active 5d14h kubernetes-dashboard Active 5d14h mynamespace Active 6s kubectl delete namespace mynamespace namespace "mynamespace" deleted to use namespaces in yaml markup simply add:

June 10, 2020 Read

Kubernetes Nodejs Postgresql Example

Deployment example with nodejs / postgresql Download Image Markup In this demo example we’ll be deploying the app from the previous docker example which consists of one node and one postgresql container. In the docker example we used a hardcoded username/password combination - which is bad practise: this time we ll be working cleaner by moving the username/password for PG into environmental variables We are going to create a deployment that uses a Secret and a ConfigMap to define values for these 2 environmental variables.

June 9, 2020 Read

Kubernetes Create Images in Azure Container Registry

Creating a Container registry @ azure For this we’ll be using the azure container registry, alternatively you can use docker.io or google/aws based services. I will name my registry demoregistry this guide will get you started dependencies for azure registry: now we login via the azure cli pacaur -S azure-cli az login az acr login --name demoregistry after the az login it will show now let’s package up the node app

June 9, 2020 Read

Kubernetes Yaml Configuration Deployment and Service

Deployment & Service Configuration Download Image Markup Connecting Deployments with Services and Pods. Every configuration in k3s has 3 types metadata spec status ( created/managed by k8/3s - differntiating between desired and actual state ) the current status is held by the k3s cluster. the attributes of each of those 3 type have different options example for deployment nginx-deployment.yaml apiVersion: apps/v1 # kind defines the type kind: Deployment # this is the metadata section metadata: name: nginx-deployment labels: # here we define a key/value pair this has to match the selector below services also reference this label app: nginx # this is the spec section spec: replicas: 3 selector: matchLabels: app: nginx # the following part is basically a configuration file inside a configuration file ( has its own metadata/spec sections ) # this is bascially the part of the configuration file that defines the pod template: metadata: # same functionality as with the label above labels: app: nginx spec: containers: - name: nginx image: nginx:1.

June 8, 2020 Read

Kubernetes K3s Cluster Using K3sup Multi Master

getting started information Terminology kubernetes: Full blown container orchestration tool minicube: a 1 node kubernetes cluster running inside a vm ( good for local testing ) k3s a lightweight alternative to Kubernetes with a lot of unneeded code removed k3sup a small extra tool that helps you getting your k3s cluster going quickly What is this docker/kuberentes stuff? *{padding:0;margin:0;overflow:hidden}html,body{height:100%}img,span{position:absolute;width:100%;top:0;bottom:0;margin:auto}span{height:1.5em;text-align:center;font:48px/1.5 sans-serif;color:white;text-shadow:0 0 0.5em black}▶" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture"

June 8, 2020 Read

Kubernetes Getting Started

Kubernetes Download Image Markup all following tutorials are done with k3s version: k3s version v1.17.2+k3s1 (cdab19b0) Node Worker Node A server - a physical or virtual machine. pods are running here. https://stackoverflow.com/questions/21889053/what-is-the-runtime-performance-cost-of-a-docker-container Master Node Manages Pods on all Worker and Master nodes Pod Abstraction ontop of a docker container. Creates running environment. Abstracting away the runtime/technology ( replace docker/containerd etc ) expect pods to be ephemeral. Service/Network each pod gets a virtual ip / internal ip.

June 7, 2020 Read

Docker Nodejs Postgresql Example

example postgresql/nodejs in two containers Download Image Markup first we need to grab the postgresql image docker pull postgres docker network ls NETWORK ID NAME DRIVER SCOPE 62e4019570d2 bridge bridge local c1aeefb374e7 host host local 608568a867c3 none null local docker network create testnetwork1 577e8e0c44c4ca0c0b1d855a70536e875bf77ec0010fdbfaf5db1d131ddabd69 docker network ls NETWORK ID NAME DRIVER SCOPE 62e4019570d2 bridge bridge local c1aeefb374e7 host host local 608568a867c3 none null local 577e8e0c44c4 testnetwork1 bridge local docker volumes: docker containers dont have persistent storage out of the box.

June 6, 2020 Read

Docker Create Images in a Private Self Hosted Registry

first we need a docker registry where we can push our own application to in this demo we ll be using a self hosted ( unsecured ) docker registry running inside docker: docker run -d -p 5000:5000 --restart=always --name registry registry:2 Unable to find image 'registry:2' locally 2: Pulling from library/registry 486039affc0a: Pull complete ba51a3b098e6: Pull complete 8bb4c43d6c8e: Pull complete 6f5f453e5f2d: Pull complete 42bc10b72f42: Pull complete Digest: sha256:7d081088e4bfd632a88e3f3bcd9e007ef44a796fddfe3261407a3f9f04abe1e7 Status: Downloaded newer image for registry:2 8c6960c8d64962c1054f617e0b141bcdbb8f234ebf3b03c9c52411b3c3062a40 then we tell docker to login: just type any username you want and an emtpy password.

June 5, 2020 Read