# GKE cluster creation and cloud shell access

> https://cloud.google.com/kubernetes-engine/docs/quickstart
> https://rafay.co/the-kubernetes-current/getting-started-with-google-kubernetes-engine-gke-0/

## connect with cloud shell, configure the environment

```
tseed@NieX0:~$ gcloud cloud-shell ssh --authorize-session
Starting your Cloud Shell machine...
Waiting for your Cloud Shell machine to start...done.
Warning: Permanently added '[34.76.250.222]:6000' (RSA) to the list of known hosts.
Welcome to Cloud Shell! Type "help" to get started.
Your Cloud Platform project in this session is set to influenzanet-321116.
Use “gcloud config set project [PROJECT_ID]” to change to a different project.
toby_n_seed@cloudshell:~ (influenzanet-321116)$

toby_n_seed@cloudshell:~ (influenzanet-321116)$ gcloud config list project
[core]
project = influenzanet-321116

toby_n_seed@cloudshell:~ (influenzanet-321116)$ gcloud config set project influenzanet-321116
Updated property [core/project].

toby_n_seed@cloudshell:~ (influenzanet-321116)$ gcloud config set compute/zone europe-west2-b
Updated property [compute/zone].
```

## build quick cluster

> API reference
> https://cloud.google.com/sdk/gcloud/reference/container/clusters/create

> available GKE versions
> https://cloud.google.com/kubernetes-engine/versioning

> single zone, multi-zone and regional cluster - we will create a single zone cluster for ease
> https://cloud.google.com/kubernetes-engine/docs/how-to/creating-a-zonal-cluster


#### Find the default version and default version for a channel for a channel

```
gcloud container get-server-config --format="yaml(defaultClusterVersion)" --zone europe-west2-b
gcloud container get-server-config --flatten="channels" --filter="channels.channel=REGULAR" --format="yaml(channels.channel,channels.validVersions)" --zone europe-west2-b
```

#### Find versions in regular channel, there are rapid and stable channels
 
```
gcloud container get-server-config --flatten="channels" --filter="channels.channel=RAPID" --format="yaml(channels.channel,channels.validVersions)" --zone europe-west2-b
```

#### Find valid image types and default image

```
gcloud container get-server-config --format="yaml(validImageTypes)" --zone europe-west2-b
gcloud container get-server-config --format="yaml(defaultImageType)" --zone europe-west2-b
```

#### Find instance types

e2-medium is the smallest recommended size for k8s nodes, this is the default.

```
gcloud compute machine-types list --filter="zone:( europe-west2-a europe-west2-b europe-west2-c )"
gcloud compute machine-types list --filter="zone:( europe-west2-b )"
```

### Create the cluster

The command is as if you'd created a cluster with defaults in a single zone.
It features a smaller ssd disk and only a single node, no scaling by node or pod is enabled.

```
gcloud container clusters create influenzanet \
--release-channel=regular \
--cluster-version=1.20.8-gke.900 \
--image-type=COS \
--num-nodes=1 \
--machine-type=e2-medium \
--disk-size=50GB \
--disk-type=pd-ssd \
--zone=europe-west2-b
```

### Delete the cluster

```
toby_n_seed@cloudshell:~ (influenzanet-321116)$ gcloud config set compute/zone europe-west2-b
Updated property [compute/zone].

toby_n_seed@cloudshell:~ (influenzanet-321116)$ gcloud container clusters list
NAME          LOCATION        MASTER_VERSION  MASTER_IP       MACHINE_TYPE  NODE_VERSION    NUM_NODES  STATUS
influenzanet  europe-west2-b  1.20.8-gke.900  35.234.142.111  e2-medium     1.20.8-gke.900  1          RUNNING

toby_n_seed@cloudshell:~ (influenzanet-321116)$ gcloud container clusters delete influenzanet
The following clusters will be deleted.
 - [influenzanet] in [europe-west2-b]

Do you want to continue (Y/n)?  y

Deleting cluster influenzanet...⠼
```

## Connect to the cluster and test ability to create workload

```
gcloud cloud-shell ssh --authorize-session

toby_n_seed@cloudshell:~ (influenzanet-321116)$ gcloud config list project
[core]
project = influenzanet-321116

toby_n_seed@cloudshell:~ (influenzanet-321116)$ gcloud config set project influenzanet-321116
Updated property [core/project].

toby_n_seed@cloudshell:~ (influenzanet-321116)$ gcloud container clusters list
NAME          LOCATION        MASTER_VERSION   MASTER_IP       MACHINE_TYPE   NODE_VERSION     NUM_NODES  STATUS
influenzanet  europe-west2-b  1.19.9-gke.1900  34.105.199.155  n1-standard-1  1.19.9-gke.1900  2          RUNNING

toby_n_seed@cloudshell:~ (influenzanet-321116)$ gcloud container clusters describe influenzanet
ERROR: (gcloud.container.clusters.describe) One of [--zone, --region] must be supplied: Please specify location.

toby_n_seed@cloudshell:~ (influenzanet-321116)$ gcloud config set compute/zone europe-west2-b
Updated property [compute/zone].

#display cluster info
toby_n_seed@cloudshell:~ (influenzanet-321116)$ gcloud container clusters describe influenzanet

#set as default cluster
toby_n_seed@cloudshell:~/cluster-management (influenzanet-321116)$ gcloud config set container/cluster influenzanet
Updated property [container/cluster].

#this is where the kubectl json creds file is auto created - very handy
toby_n_seed@cloudshell:~/cluster-management (influenzanet-321116)$ gcloud container clusters get-credentials influenzanet
Fetching cluster endpoint and auth data.
kubeconfig entry generated for influenzanet.

#test connectivity with kubectl
toby_n_seed@cloudshell:~ (influenzanet-321116)$ kubectl cluster-info
Kubernetes control plane is running at https://35.197.223.199
GLBCDefaultBackend is running at https://35.197.223.199/api/v1/namespaces/kube-system/services/default-http-backend:http/proxy
KubeDNS is running at https://35.197.223.199/api/v1/namespaces/kube-system/services/kube-dns:dns/proxy
Metrics-server is running at https://35.197.223.199/api/v1/namespaces/kube-system/services/https:metrics-server:/proxy

To further debug and diagnose cluster problems, use 'kubectl cluster-info dump'.
```