HelmChat

 

What is helm?

Helm is a Kubernetes package and operations manager,  A Helm chart will usually contain at least a Deployment and a Service, but it can also contain an Ingress, Persistent Volume Claims, or any other Kubernetes object. Helm charts are used to deploy an application, or one component of a larger application

 

Helm can be useful in different scenarios

• Find and use popular software packaged as Kubernetes charts
• Share your own applications as Kubernetes charts
• Create reproducible builds of your Kubernetes applications
• Intelligently manage your Kubernetes object definitions
• Manage releases of Helm packages

 

 

 

 

Making Kubernetes Cluster

In this lesson we will do a quick review of getting a Kubernetes cluster up and running. This will be the basis for all of the future work that we do using Helm. We will also cover the installation of the Rook volume provisioner. All of this takes place on our Cloud Playground servers using the Cloud Native Kubernetes image.

During the installation you might see a warning message in the pre-flight checks indicating that the version of Docker is not validated. It is safe to ignore this warning, the version of Docker that is installed works correctly with the installed Kubernetes version

We will be installing version 1.13.12 of Kubernetes using the following commands on all servers/nodes.

apt install -y docker.io

systemctl enable docker

curl -s https://packages.cloud.google.com/apt/doc/apt-key.gpg | apt-key add -

cat <<EOF >/etc/apt/sources.list.d/kubernetes.list

deb http://apt.kubernetes.io/ kubernetes-xenial main

EOF

apt-get update

apt-get install -y kubeadm=1.13\* kubectl=1.13\* kubelet=1.13\* kubernetes-cni=0.7\*

On the master node we will run the init command for the version of Kubernetes that we are installing. The following commands are run only on the master node.

kubeadm init --kubernetes-version stable-1.13 --token-ttl 0 --pod-network-cidr=10.244.0.0/16

be sure that you run the token command on the worker nodes, also you need to run the post install commands to make the .kube directory and cp the config and chown it.

Then install flannel,

kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml

Make sure that you get the correct version of rook, in this course we are using rook 0.9

git clone https://github.com/linuxacademy/content-kubernetes-helm.git ./rook

cd ./rook/cluster/examples/kubernetes/ceph

 

 

kubectl create -f operator.yaml

Once the agent, operator and discover pods are started in the rook-ceph-system namespace then setup the cluster

kubectl create -f cluster.yaml

Once this is run wait for the appearance of the OSD pods in the name space rook-ceph

kubectl get pods -n rook-ceph

Create a storage class so that we can attach to it.

kubectl create -f storageclass.yaml

 

 

 

 

 

 

 

 

 

 

 

 

Installing helm and triller:

 

In this lesson, we will look at installing Helm using available packages. These methods include package management with Snap and installing from binaries that are precompiled.
As some commands have changed in recent versions, please ensure that you are installing the same version that is being installed in the video.

We will explore the commands:

helm init

as well as:

helm init --upgrade

 

 

 

Installing Helm and Tiller part 2

 

In this lesson we continue with the installation of Helm and Tiller as we compile the Helm binaries from source code. We will also quickly cover in setup of the golang environment required to compile Helm. Once we have the binaries available we will install Helm and Tiller. Then we'll discuss service accounts and ensure that our installation is able to create a release.

The installation for golang can be found at :

https://golang.org/doc/install

The glide project is located at:

https://github.com/Masterminds/glide

The official helm repo is located at

https://github.com/helm/helm

Here is a command reference for this lesson:

Build command for Helm:

make bootstrap build

Kubernetes service account:

kubectl create serviceaccount --namespace kube-system tiller

kubectl create clusterrolebinding tiller-cluster-rule --clusterrole=cluster-admin --serviceaccount=kube-system:tiller

kubectl patch deploy --namespace kube-system tiller-deploy -p '{"spec":{"template":{"spec":{"serviceAccount":"tiller"}}}}'