k8s

Originally kubernetes offered Kompose, which lets you quickly ramp up to Kubernetes by turning your existing docker-compose.yml file into Kubernetes resources. At the end of 2018 docker announced Compose on Kubernetes. The Kompose team state that they’ll continue to support Kompose.

az group create -n myGroup
az configure --defaults group=myGroup
az acr create -n myRegistry --sku basic
az acr login -n myRegistry
az aks create -n myCluster \
    --node-count 1 \
    --node-vm-size Standard_B2s \
    --load-balancer-sku basic \
    --node-osdisk-size 32 \
    --attach-acr myRegistry
az aks get-credentials --name myCluster

Because I often get the following;

Operation failed with status: ‘Bad Request’. Details: The credentials in ServicePrincipalProfile were invalid. Please see https://aka.ms/aks-sp-help for more details. (Details: adal: Refresh request failed. Status Code = ‘400’. Response body: {“error”:”unauthorized_client”,”error_description”:”AADSTS700016: Application with identifier > ‘' was not found in the directory ''. This can happen if the application has not been installed by the administrator of the tenant or consented to by any user in the tenant. You may have sent your authentication request to the wrong tenant.

Instead I do this;

az ad sp create-for-rbac --skip-assignment -n mySP
az aks create -n tye --generate-ssh-keys --node-count 1 --node-vm-size Standard_B2s --service-principal <appId-from-previous-command> --client-secret <password-from-previous-command>

Github issue

Set the KUBE_EDITOR environment variable to code -w. Then you can do stuff like

kubectl edit deployment -n kube-system kube-dns-v20

Don’t install go, instead build it inside the go container;

docker run --rm -v %CD%:/go/src/github.com/prometheus/prometheus -w /go/src/github.com/prometheus/prometheus golang:1.10 make build

Run it inside that docker container too!

docker run --rm -v %CD%:/go/src/github.com/prometheus/prometheus -w /go/src/github.com/prometheus/prometheus -p 9090:9090 golang:1.10 ./prometheus

Note: I executed the following to have it use a test config;

copy ./config/testdata/conf.good.yml ./prometheus.yml

kubectl create clusterrolebinding kubernetes-dashboard --clusterrole=cluster-admin --serviceaccount=kube-system:kubernetes-dashboard
az aks browse -n myCluster

Docs

Follow docs on cert-manager

kubectl create job --from=cronjob/postgres-backup-digital-icebreakers backup-now-$(date +"%Y-%m-%d")

Kill pod

kubectl delete pod <name-of-pod> --grace-period=0 --force

Review node resource allocation

kubectl describe node

Delete all errored pods

kubectl get pod | grep Error | awk '{print $1}' | xargs kubectl delete pod

Edit manifest in-place

kubectl edit deployments <name-of-deployment>