OKE

This section shows how to create a Container Engine for Kubernetes cluster.

Assuming that you already had created a Virtual Cloud Network with the pre-requisites to create an OKE cluster, and that you have the OCI-CLI configured, you can continue to create a cluster. We use the following characteristics which you might change:

  • Compartment: Select or create a compartment to allocate the deployment
  • Cluster name: stackgres
  • Kubernetes version: v1.21.5
  • Node Shape: VM.Standard.E4.Flex
  • OCPU per node: 1
  • Memory per node: 8 GB
  • Number of nodes: 3
  • Disk size: 50 GB
  • VCN with 3 different subnets: Kubernetes Endpoint Subnet; Load Balancer Subnet; Node Pool Subnet

This is an example to create a OKE cluster into a single AD

Create the necessary environment variables and replace the values with your tenancy information:

export compartment_id=[compartment-OCID]
export vnc_id=[VNC-OCID]
export endpoint_subnet_id=[endpoint-subnet-OCID]
export lb_subnet_id=[loadbalancer-subnet-OCID]
export nodes_subnet_id=[nodes-subnet-OCID]

Create the Kubernetes Cluster:

oci ce cluster create \
 --compartment-id $compartment_id \
 --kubernetes-version v1.21.5 \
 --name stackgres \
 --vcn-id $vnc_id \
 --endpoint-subnet-id $endpoint_subnet_id \
 --service-lb-subnet-ids '["'$lb_subnet_id'"]' \
 --endpoint-public-ip-enabled true \
 --persistent-volume-freeform-tags '{"stackgres" : "OKE"}'

The output will be similar to this:

   {
  ""opc-work-request-id": "ocid1.clustersworkrequest.oc1.[OCI-Regions].aaaaaaaa2p26em5geexn...""
   }

After the Cluster creation, create the node pool for the Kubernetes worker nodes:

oci ce node-pool create \
 --cluster-id $(oci ce cluster list --compartment-id $compartment_id --name stackgres --lifecycle-state ACTIVE --query data[0].id --raw-output) \
 --compartment-id $compartment_id \
 --kubernetes-version v1.21.5 \
 --name Pool1 \
 --node-shape VM.Standard.E4.Flex \
 --node-shape-config '{"memoryInGBs": 8.0, "ocpus": 1.0}' \
 --node-image-id $(oci compute image list --operating-system 'Oracle Linux' --operating-system-version 7.9 --sort-by TIMECREATED --compartment-id $compartment_id --query data[1].id --raw-output) \
 --node-boot-volume-size-in-gbs 50 \
 --size 3 \
 --placement-configs '[{"availabilityDomain": "'$(oci iam availability-domain list --compartment-id $compartment_id --query data[0].name --raw-output)'", "subnetId": "'$nodes_subnet_id'"}]'

The output will be similar to this:

   {
  "opc-work-request-id": "ocid1.clustersworkrequest.oc1.[OCI-Regions].aaaaaaaa2p26em5geexn..."
   }

After the cluster provisioning, it is highly recommend to change the default Kubernetes storage class:

kubectl patch storageclass oci -p '{"metadata": {"annotations":{"storageclass.beta.kubernetes.io/is-default-class":"false"}}}'
kubectl patch storageclass oci-bv -p '{"metadata": {"annotations":{"storageclass.beta.kubernetes.io/is-default-class":"true"}}}'

To clean up the Kubernetes cluster you can issue following:

Delete the node pool:

oci ce node-pool delete \
 --node-pool-id $(oci ce node-pool list --cluster-id $(oci ce cluster list --compartment-id $compartment_id --name stackgres --lifecycle-state ACTIVE --query data[0].id --raw-output) --compartment-id $compartment_id --query data[0].id --raw-output) \
 --force

Delete the Kubernetes cluster:

oci ce cluster delete \
 --cluster-id $(oci ce cluster list --compartment-id $compartment_id --name stackgres --lifecycle-state ACTIVE --query data[0].id --raw-output) \
 --force

You may also want to clean up compute disks used by persistence volumes that may have been created:

This code terminates all Block Volumes with the Free Form Tag {“stackgres”:“OKE”}, if you had provisioned more than one cluster in the same compartment with the code above, this may delete all your PV data.

oci bv volume list \
 --compartment-id $compartment_id \
 --lifecycle-state AVAILABLE \
 --query 'data[?"freeform-tags".stackgres == '\''OKE'\''].id' \
  | jq -r .[] | xargs -r -n 1 -I % oci bv volume delete --volume-id % --force