Setup a Kubernetes Cluster
This is work in progress. We will add its sections in pieces. Your feedback is welcome at discuss.istio.io.
In this module, you set up a Kubernetes cluster that has Istio installed and a namespace to use throughout the tutorial.
If you are in a workshop and the instructors provide a cluster for you, proceed to setting up your local computer.
Ensure you have access to a Kubernetes cluster. You can use the Google Kubernetes Engine or the IBM Cloud Kubernetes Service.
Create an environment variable to store the name of a namespace that you will use when you run the tutorial commands. You can use any name, for example
tutorial
.$ export NAMESPACE=tutorial
Create the namespace:
$ kubectl create namespace $NAMESPACE
If you are an instructor, you should allocate a separate namespace per each participant. The tutorial supports work in multiple namespaces simultaneously by multiple participants.
Install Istio using the
demo
profile.The Kiali and Prometheus addons are used in this example and need to be installed. All addons are installed using:
$ kubectl apply -f @samples/addons@
If there are errors trying to install the addons, try running the command again. There may be some timing issues which will be resolved when the command is run again.
Create a Kubernetes Ingress resource for these common Istio services using the
kubectl
command shown. It is not necessary to be familiar with each of these services at this point in the tutorial.The
kubectl
command can accept an in-line configuration to create the Ingress resources for each service:$ kubectl apply -f - <<EOF
apiVersion: networking.k8s.io/v1beta1
kind: Ingress
metadata:
name: istio-system
namespace: istio-system
annotations:
kubernetes.io/ingress.class: istio
spec:
rules:
- host: my-istio-dashboard.io
http:
paths:
- path: /
pathType: Prefix
backend:
serviceName: grafana
servicePort: 3000
- host: my-istio-tracing.io
http:
paths:
- path: /
pathType: Prefix
backend:
serviceName: tracing
servicePort: 9411
- host: my-istio-logs-database.io
http:
paths:
- path: /
pathType: Prefix
backend:
serviceName: prometheus
servicePort: 9090
- host: my-kiali.io
http:
paths:
- path: /
pathType: Prefix
backend:
serviceName: kiali
servicePort: 20001
EOF
Create a role to provide read access to the
istio-system
namespace. This role is required to limit permissions of the participants in the steps below.$ kubectl apply -f - <<EOF
kind: Role
apiVersion: rbac.authorization.k8s.io/v1beta1
metadata:
name: istio-system-access
namespace: istio-system
rules:
- apiGroups: ["", "extensions", "apps"]
resources: ["*"]
verbs: ["get", "list"]
EOF
Create a service account for each participant:
$ kubectl apply -f - <<EOF
apiVersion: v1
kind: ServiceAccount
metadata:
name: ${NAMESPACE}-user
namespace: $NAMESPACE
EOF
Limit each participant’s permissions. During the tutorial, participants only need to create resources in their namespace and to read resources from
istio-system
namespace. It is a good practice, even if using your own cluster, to avoid interfering with other namespaces in your cluster.Create a role to allow read-write access to each participant’s namespace. Bind the participant’s service account to this role and to the role for reading resources from
istio-system
:$ kubectl apply -f - <<EOF
kind: Role
apiVersion: rbac.authorization.k8s.io/v1beta1
metadata:
name: ${NAMESPACE}-access
namespace: $NAMESPACE
rules:
- apiGroups: ["", "extensions", "apps", "networking.k8s.io", "networking.istio.io", "authentication.istio.io",
"rbac.istio.io", "config.istio.io", "security.istio.io"]
resources: ["*"]
verbs: ["*"]
---
kind: RoleBinding
apiVersion: rbac.authorization.k8s.io/v1beta1
metadata:
name: ${NAMESPACE}-access
namespace: $NAMESPACE
subjects:
- kind: ServiceAccount
name: ${NAMESPACE}-user
namespace: $NAMESPACE
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: Role
name: ${NAMESPACE}-access
---
kind: RoleBinding
apiVersion: rbac.authorization.k8s.io/v1beta1
metadata:
name: ${NAMESPACE}-istio-system-access
namespace: istio-system
subjects:
- kind: ServiceAccount
name: ${NAMESPACE}-user
namespace: $NAMESPACE
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: Role
name: istio-system-access
EOF
Each participant needs to use their own Kubernetes configuration file. This configuration file specifies the cluster details, the service account, the credentials and the namespace of the participant. The
kubectl
command uses the configuration file to operate on the cluster.Generate a Kubernetes configuration file for each participant:
This command assumes your cluster is named
tutorial-cluster
. If your cluster is named differently, replace all references with the name of your cluster.$ cat <<EOF > ./${NAMESPACE}-user-config.yaml
apiVersion: v1
kind: Config
preferences: {}
clusters:
- cluster:
certificate-authority-data: $(kubectl get secret $(kubectl get sa ${NAMESPACE}-user -n $NAMESPACE -o jsonpath={.secrets..name}) -n $NAMESPACE -o jsonpath='{.data.ca\.crt}')
server: $(kubectl config view -o jsonpath="{.clusters[?(.name==\"$(kubectl config view -o jsonpath="{.contexts[?(.name==\"$(kubectl config current-context)\")].context.cluster}")\")].cluster.server}")
name: ${NAMESPACE}-cluster
users:
- name: ${NAMESPACE}-user
user:
as-user-extra: {}
client-key-data: $(kubectl get secret $(kubectl get sa ${NAMESPACE}-user -n $NAMESPACE -o jsonpath={.secrets..name}) -n $NAMESPACE -o jsonpath='{.data.ca\.crt}')
token: $(kubectl get secret $(kubectl get sa ${NAMESPACE}-user -n $NAMESPACE -o jsonpath={.secrets..name}) -n $NAMESPACE -o jsonpath={.data.token} | base64 --decode)
contexts:
- context:
cluster: ${NAMESPACE}-cluster
namespace: ${NAMESPACE}
user: ${NAMESPACE}-user
name: ${NAMESPACE}
current-context: ${NAMESPACE}
EOF
Set the
KUBECONFIG
environment variable for the${NAMESPACE}-user-config.yaml
configuration file:$ export KUBECONFIG=$PWD/${NAMESPACE}-user-config.yaml
Verify that the configuration took effect by printing the current namespace:
$ kubectl config view -o jsonpath="{.contexts[?(@.name==\"$(kubectl config current-context)\")].context.namespace}"
tutorial
You should see the name of your namespace in the output.
If you are setting up the cluster for yourself, copy the
${NAMESPACE}-user-config.yaml
file mentioned in the previous steps to your local computer, where${NAMESPACE}
is the name of the namespace you provided in the previous steps. For example,tutorial-user-config.yaml
. You will need this file later in the tutorial.If you are an instructor, send the generated configuration files to each participant. The participants must copy their configuration file to their local computer.
Congratulations, you configured your cluster for the tutorial!
You are ready to setup a local computer.