There are a few ways to handle data persistence on Kubernetes. Today we will dive into configuration of the OSS OpenEBS project.
Workshop attendees will receive an email with the instance info prior to the workshop.
Notice that training cloud instances will be available only during the workshop and will be terminated 12-24 hours later. If you are in our workshop, we recommend using the provided cloud instance; we have you covered: the prerequisites are installed.
⚡ IMPORTANT NOTE:
Everywhere in this repository you see <YOURADDRESS> replace with the URL for the instance you were given.
- [Presentation](PDF OF SLIDES HERE)
- Discord chat
| Title | Description |
|---|---|
| 1 - Getting Connected | Instructions |
| 2 - Setting up OpenEBS | Instructions |
| 3 - Create a Storage Class | Instructions |
| 4 - Create a Persistent Volume Claim | Instructions |
| 5 - Create a Pod and Attach the PVC | Instructions |
| 6 - Verify Everything | Instructions |
| 7 - Spin it All Down | Instructions |
| 8 - Resources | Instructions |
✅ Step 1a: The first step in the section.
In your browser window, navigate to the url :3000 where your address is the one emailed to you before the session.
When you arrive at the webpage you should be greeted by something similar to this.
Click in the Terminal menu from the top of the page and select new terminal as shown below
Once you have opened the terminal run
kubectl get nodes📃output
NAME STATUS ROLES AGE VERSION
learning-cluster-master Ready master 49m v1.19.4
learning-cluster-worker-0 Ready <none> 49m v1.19.4
learning-cluster-worker-1 Ready <none> 49m v1.19.4
ubuntu@learning-cluster-master:~/workshop$ If you see the above output you are ready for the lab.
✅ Step 1: Check what Pods are running currently.
kubectl get pods --all-namespaces📃output
NAMESPACE NAME READY STATUS RESTARTS AGE
kube-system coredns-f9fd979d6-fbhvf 1/1 Running 0 97m
kube-system coredns-f9fd979d6-p95s2 1/1 Running 0 97m
kube-system etcd-learning-cluster-master 1/1 Running 0 97m
kube-system kube-apiserver-learning-cluster-master 1/1 Running 0 97m
kube-system kube-controller-manager-learning-cluster-master 1/1 Running 0 97m
kube-system kube-flannel-ds-kg2rb 1/1 Running 0 96m
kube-system kube-flannel-ds-kjhh5 1/1 Running 0 96m
kube-system kube-flannel-ds-ztdjh 1/1 Running 0 96m
kube-system kube-proxy-nrqmf 1/1 Running 0 97m
kube-system kube-proxy-p45s8 1/1 Running 0 97m
kube-system kube-proxy-stqtm 1/1 Running 0 97m
kube-system kube-scheduler-learning-cluster-master 1/1 Running 0 97m✅ Step 2: Get the operator yaml file and deploy it.
wget https://openebs.github.io/charts/openebs-operator.yaml
kubectl apply -f openebs-operator.yaml📃output
namespace/openebs created
serviceaccount/openebs-maya-operator created
...
clusterrolebinding.rbac.authorization.k8s.io/openebs-maya-operator created
deployment.apps/maya-apiserver created
service/maya-apiserver-service created
deployment.apps/openebs-provisioner created
deployment.apps/openebs-snapshot-operator created
configmap/openebs-ndm-config created
daemonset.apps/openebs-ndm created
deployment.apps/openebs-ndm-operator created
deployment.apps/openebs-admission-server created
deployment.apps/openebs-localpv-provisioner created✅ Step 3: Check to see the new OpenEBS pods.
kubectl get pods --all-namespaces📃output
NAMESPACE NAME READY STATUS RESTARTS AGE
kube-system coredns-f9fd979d6-ln2v7 1/1 Running 0 9m49s
kube-system coredns-f9fd979d6-qmddk 1/1 Running 0 9m49s
kube-system etcd-learning-cluster-0-master 1/1 Running 0 10m
kube-system kube-apiserver-learning-cluster-0-master 1/1 Running 0 10m
kube-system kube-controller-manager-learning-cluster-0-master 1/1 Running 0 10m
kube-system kube-flannel-ds-bf4fw 1/1 Running 0 2m40s
kube-system kube-flannel-ds-lzwfg 1/1 Running 0 2m40s
kube-system kube-flannel-ds-sklwv 1/1 Running 0 2m40s
kube-system kube-proxy-4n8z5 1/1 Running 0 3m
kube-system kube-proxy-f8kf2 1/1 Running 0 2m47s
kube-system kube-proxy-ld922 1/1 Running 0 9m49s
kube-system kube-scheduler-learning-cluster-0-master 1/1 Running 0 10m
openebs maya-apiserver-64b7cfd966-ts7wg 0/1 Running 3 74s
openebs openebs-admission-server-dfcc899d4-kq6lq 1/1 Running 0 73s
openebs openebs-localpv-provisioner-7f5c4cd4cf-kkvgl 1/1 Running 0 73s
openebs openebs-ndm-9cdcx 1/1 Running 0 73s
openebs openebs-ndm-flt9m 1/1 Running 0 73s
openebs openebs-ndm-operator-85bb97d5f7-x5bkq 1/1 Running 0 73s
openebs openebs-provisioner-fc4f45bbb-rvv69 1/1 Running 0 74s
openebs openebs-snapshot-operator-856d75cbb9-vj2r6 2/2 Running 0 74s✅ Step 1: Look at the drives we have connected to our nodes.
ssh worker0
lsblk -f📃output
NAME FSTYPE LABEL UUID MOUNTPOINT
loop0 squashfs /snap/core/9993
loop1 squashfs /snap/amazon-ssm-agent
loop2 squashfs /snap/core/10823
loop3 squashfs /snap/core18/1988
loop4 squashfs /snap/amazon-ssm-agent
nvme1n1
nvme0n1
└─nvme0n1p1 ext4 cloudimg-rootfs 4dc427d0-74d1-4d90-a452-2cfdb7538e46 /Notice the NVMe drives connected. To exit the worker node simply run
exit✅ Step 1: Tag Block Devices.
First we need to see what block devices we have access to.
kubectl get blockdevice -n openebs📃output
NAME NODENAME SIZE CLAIMSTATE STATUS AGE
blockdevice-00a153d28d33527f7614abfeb2700329 learning-cluster-0-worker-0 75000000000 Unclaimed Active 66m
blockdevice-0b4e70565b4d5193724c1c97e59d9ed2 learning-cluster-0-worker-1 75000000000 Unclaimed Active 66mkubectl label bd -n openebs BLOCKDEVICENAMEHERE openebs.io/block-device-tag=learning
kubectl label bd -n openebs BLOCKDEVICENAMEHERE openebs.io/block-device-tag=learning✅ Step 2: Setup the Storage Class.
kubectl apply -f local-device-sc.yaml📃output
storageclass.storage.k8s.io/local-device created✅ Step 3: Verify the Storage Class created.
kubectl get sc local-device📃output
NAME PROVISIONER RECLAIMPOLICY VOLUMEBINDINGMODE ALLOWVOLUMEEXPANSION AGE
local-device openebs.io/local Delete WaitForFirstConsumer false 4m28s✅ Step 1: Setup the Persistant Volume Claim.
wget https://openebs.github.io/charts/examples/local-device/local-device-pvc.yaml
kubectl apply -f local-device-pvc.yaml📃output
persistentvolumeclaim/local-device-pvc created✅ Step 2: Verify the PVC is in a pending state.
kubectl get pvc local-device-pvc📃output
NAME STATUS VOLUME CAPACITY ACCESS MODES STORAGECLASS AGE
local-device-pvc Pending local-device 30s✅ Step 1: Setup the pod.
wget https://openebs.github.io/charts/examples/local-device/local-device-pod.yaml
kubectl apply -f local-device-pod.yaml📃output
pod/hello-local-device-pod created✅ Step 2: Verify our configuration starting with our new pod.
kubectl get pod hello-local-device-pod📃output
NAME READY STATUS RESTARTS AGE
hello-local-device-pod 1/1 Running 0 2m55s✅ Step 3: Verify the pod is using the Local PV Device we setup.
kubectl describe pod hello-local-device-pod📃output
Name: hello-local-device-pod
Namespace: default
Priority: 0
Node: learning-cluster-0-worker-0/10.0.1.66
Start Time: Mon, 15 Feb 2021 05:43:23 +0000
Labels: <none>
Annotations: <none>
Status: Running
...
Events:
Type Reason Age From Message
---- ------ ---- ---- -------
Normal Scheduled 3m34s default-scheduler Successfully assigned default/hello-local-device-pod to learning-cluster-0-worker-0
Normal Pulling 3m34s kubelet Pulling image "busybox"
Normal Pulled 3m33s kubelet Successfully pulled image "busybox" in 608.838949ms
Normal Created 3m33s kubelet Created container hello-container
Normal Started 3m33s kubelet Started container hello-container✅ Step 1: Look at the configuration of the Persistant Volume Claim.
kubectl get pvc local-device-pvc📃output
NAME STATUS VOLUME CAPACITY ACCESS MODES STORAGECLASS AGE
local-device-pvc Bound pvc-1d1e53c2-897e-48dc-aeb3-485bc2a593a6 5G RWO local-device 4m41s✅ Step 2: Check your PVC configuration.
Use the id under the VOLUME column in the output of the previous step in place of YOURPVCID
kubectl get pv YOURPVCID -o yaml📃output
apiVersion: v1
kind: PersistentVolume
metadata:
annotations:
local.openebs.io/blockdeviceclaim: bdc-pvc-1d1e53c2-897e-48dc-aeb3-485bc2a593a6
pv.kubernetes.io/provisioned-by: openebs.io/local
creationTimestamp: "2021-02-15T05:43:22Z"
finalizers:
- kubernetes.io/pv-protection
...
status:
phase: Bound✅ Step 3: Get the name of the block device.
kubectl get bdc -n openebs bdc-YOURPVCID📃output
NAME BLOCKDEVICENAME PHASE AGE
bdc-pvc-1d1e53c2-897e-48dc-aeb3-485bc2a593a6 blockdevice-00a153d28d33527f7614abfeb2700329 Bound 10m✅ Step 4: Check the block device config.
kubectl get bd -n openebs YOURBLOCKDEVICENAME -o yaml📃output
apiVersion: openebs.io/v1alpha1
kind: BlockDevice
metadata:
annotations:
internal.openebs.io/uuid-scheme: gpt
creationTimestamp: "2021-02-15T04:30:10Z"
finalizers:
- openebs.io/bd-protection
generation: 2
labels:
kubernetes.io/hostname: learning-cluster-0-worker-0
ndm.io/blockdevice-type: blockdevice
ndm.io/managed: "true"
openebs.io/block-device-tag: learning
managedFields:
- apiVersion: openebs.io/v1alpha1
...
devlinks:
- kind: by-id
links:
- /dev/disk/by-id/nvme-Amazon_EC2_NVMe_Instance_Storage_AWS283E87F715A24F5CC
- /dev/disk/by-id/nvme-nvme.1d0f-4157533238334538374637313541323446354343-416d617a6f6e20454332204e564d6520496e7374616e63652053746f72616765-00000001
- kind: by-path
links:
- /dev/disk/by-path/pci-0000:00:1f.0-nvme-1
filesystem: {}
nodeAttributes:
nodeName: learning-cluster-0-worker-0
partitioned: "No"
path: /dev/nvme1n1
status:
claimState: Claimed
state: Active✅ Step 1: Delete everything.
kubectl delete pod hello-local-device-pod
kubectl delete pvc local-device-pvc
kubectl delete sc local-device✅ Step 2: Check the PV.
kubectl get pv📃output
No resources foundFor further reading go to the OpenEBS Docs Check out our new Discord server Invite Get into more with the Data On Kubernetes Community DOKc Many more workshops to come so Please subscribe to the YouTube Channel to be notified.