Tutorial

How to set up shared file system (ReadWriteMany, RWX) persistent volumes on Kubernetes with Quobyte

Shared file systems in Kubernetes are great for data hungry stateful applications like analytics, machine learning or dev workloads like compile and test. This 5 minute tutorial shows you how to connect your Kubernetes cluster to Quobyte and serve persistent volumes.

Contents

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Quobyte is a software-only distributed file system that runs on almost any x86 server, either as an application on the host or in containers itself. In this tutorial, we’ll show you how to configure your Kubernetes cluster to use an external Quobyte cluster to provide persistent volumes.

Quobyte’s software storage handles your data as flexibly as containers and provides a simple storage management solution. Quobyte is built to run and integrate seamlessly with Kubernetes.

This tutorial shows how to connect a Kubernetes cluster to a Quobyte storage cluster and how you can use it for dynamic provisioning of volumes.

This example does not assume that your Quobyte cluster runs on Kubernetes; although it can be an option. For the scope of this tutorial, we are going to focus on integrating your Kubernetes cluster with Quobyte, totally agnostic of where and how the Quobyte cluster is running.

Step-by-Step Tutorial

  1. Kubernetes Cluster

    We start with a freshly created k8s cluster:

    [jan@jan quobyte-k8s-helm]$ kubectl get nodes
    NAME                                    STATUS   ROLES    AGE   VERSION
    gke-bbtest-default-pool-dcc88ad3-mr6m   Ready       62s   v1.16.15-gke.4300
    gke-bbtest-default-pool-dcc88ad3-pn68   Ready       62s   v1.16.15-gke.4300
    gke-bbtest-default-pool-dcc88ad3-t6f8   Ready       61s   v1.16.15-gke.4300
  2. Quobyte Cluster

    On the other hand, we need a Quoybte Cluster to connect to - the Free Edition is totally sufficient; you can follow the instructions to download and install it here.

    Next, we need information to configure the Quobyte Helm chart to connect successfully to our Quobyte cluster:

    1. Quobyte API endpoint address
    2. All the registry addresses
    3. A valid pair of Quobyte credentials (username/ password in this example)
  3. Fetch API service overview
    deploy@smallscale-coreserver0:~$ qmgmt service list | grep AP
    smallscale-coreserver0.c.quobyte-eng.internal  API Proxy (A)  316ce70a-3838-4872-95aa-5ff546a0f5c8  *             
    smallscale-coreserver1.c.quobyte-eng.internal  API Proxy (A)  8e953778-670d-4871-bc91-b5ce0a011257  *             
    smallscale-coreserver2.c.quobyte-eng.internal  API Proxy (A)  7c59eed9-3716-4f8f-89ef-38db3cef21a7  *             
    smallscale-coreserver3.c.quobyte-eng.internal  API Proxy (A)  d2496866-3744-4170-8675-061024a6f377  *
  4. Get the Quobyte registry addresses

    Here we have a Quobyte cluster with four nodes, the registry, and also the API service running potentially on all of them.

    deploy@smallscale-coreserver0:~$ grep ^registry /etc/quobyte/host.cfg 
    registry=10.138.0.43,10.138.0.45,10.138.0.46,10.138.0.49
  5. Create a dedicated Quobyte user for Kubernetes

    Note: With a fully licensed Quobyte version you can benefit from different roles/ true multi-tenancy; this is skipped in this tutorial since our scope is limited to the free version of Quobyte.

    deploy@smallscale-coreserver0:~$ qmgmt user config add jan-kubernaut jan.peschke@quobyte.com SUPER_USER password change-me_later
    Success. Added user 'jan-kubernaut'
  6. Kubernetes Cluster

    Now that you have a Quobyte cluster up and running, we switch to setting up the Kubernetes cluster. We assume that kubectl is working, and Helm is installed and usable.

  7. Check out the Quobyte Helm chart:
    $ git clone https://github.com/quobyte/quobyte-k8s-helm.git
    $ cd quobyte-k8s-helm
  8. Modify "values.yaml" to not install the Quobyte cluster into our k8s cluster
  9. Encode secret + username to base64:
    [jan@jan quobyte-k8s-helm]$ echo -n "change-me_later" | base64 
    Y2hhbmdlLW1lX2xhdGVy
    [jan@jan quobyte-k8s-helm]$ echo -n "jan-kubernaut" | base64 
    amFuLWt1YmVybmF1dA==
  10. Add these credentials also into values.yaml
    [jan@jan quobyte-k8s-helm]$ vi values.yaml 
    [jan@jan quobyte-k8s-helm]$ cat values.yaml 
    # Enables the Quobyte CSI plugin if set to true.
    # Please configure the CSI plugin in charts/quobyte-csi/values.yaml
    csi_enabled: true
    # Enables automatic Quobyte client deployments if set to true.
    # Must be enabled and configured when using the CSI plugin.
    # Please configure in charts/quobyte-client/values.yaml
    client_enabled: true 
    # Enables the provisioning of Quobyte services if set to true.
    # Please consult the readme for requirements for running
    # the Quobyte services on Kubernetes.
    # Please configure in charts/quobyte-core/values.yaml
    core_enabled: false 
    # configure client:
    #
    quobyte-client:
      quobyte:
        clientImage: gcr.io/eda-eval/quobyte-client:3.0.pre8
        registry: 10.138.0.43,10.138.0.45,10.138.0.46,10.138.0.49 
    # configure CSI plugin:
    #
    quobyte-csi:
      quobyte: 
        quobyteTenant: "My Tenant"
        quobyteUser: amFuLWt1YmVybmF1dA== 
        quobytePassword: Y2hhbmdlLW1lX2xhdGVy 
        apiURL: http://10.138.0.43:7860
  11. After the values.yaml looks like the one above it is time to install the helm chart:
    $ helm install client-and-csi . -f values.yaml --debug
  12. Verification

    We can now verify that we have a setup without any recent restarting pods.

    • Any csi- and quobyte-client pods should run without any errors.

    [jan@jan quobyte-k8s-helm]$ kubectl get pods -A
    NAMESPACE     NAME                                                        READY   STATUS    RESTARTS   AGE
    default       quobyte-client-ds-5bj8x                                     1/1     Running   0          2m34s
    default       quobyte-client-ds-f9xbr                                     1/1     Running   0          2m34s
    default       quobyte-client-ds-qjnqc                                     1/1     Running   0          2m34s
    kube-system   event-exporter-gke-77cccd97c6-6qctn                         2/2     Running   0          67m
    kube-system   fluentd-gke-95bsm                                           2/2     Running   0          65m
    kube-system   fluentd-gke-lhwkf                                           2/2     Running   0          65m
    kube-system   fluentd-gke-scaler-54796dcbf7-mz99l                         1/1     Running   0          67m
    kube-system   fluentd-gke-wzdqg                                           2/2     Running   0          66m
    kube-system   gke-metrics-agent-59rbs                                     1/1     Running   0          67m
    kube-system   gke-metrics-agent-5ps8j                                     1/1     Running   0          67m
    kube-system   gke-metrics-agent-dwlmp                                     1/1     Running   0          67m
    kube-system   kube-dns-7bb4975665-j2fqx                                   4/4     Running   0          67m
    kube-system   kube-dns-7bb4975665-l58d6                                   4/4     Running   0          67m
    kube-system   kube-dns-autoscaler-645f7d66cf-r2h49                        1/1     Running   0          67m
    kube-system   kube-proxy-gke-bbtest-default-pool-dcc88ad3-mr6m            1/1     Running   0          67m
    kube-system   kube-proxy-gke-bbtest-default-pool-dcc88ad3-pn68            1/1     Running   0          67m
    kube-system   kube-proxy-gke-bbtest-default-pool-dcc88ad3-t6f8            1/1     Running   0          67m
    kube-system   l7-default-backend-678889f899-t4nz7                         1/1     Running   0          67m
    kube-system   metrics-server-v0.3.6-64655c969-k5gd9                       2/2     Running   0          67m
    kube-system   prometheus-to-sd-2l4wc                                      1/1     Running   0          67m
    kube-system   prometheus-to-sd-rw296                                      1/1     Running   0          67m
    kube-system   prometheus-to-sd-w429c                                      1/1     Running   0          67m
    kube-system   quobyte-csi-controller-csi-quobyte-com-0                    5/5     Running   0          2m34s
    kube-system   quobyte-csi-node-csi-quobyte-com-4l47v                      2/2     Running   0          2m34s
    kube-system   quobyte-csi-node-csi-quobyte-com-gj5dq                      2/2     Running   0          2m34s
    kube-system   quobyte-csi-node-csi-quobyte-com-gjnsx                      2/2     Running   0          2m34s
    kube-system   stackdriver-metadata-agent-cluster-level-756cbb8bb5-f7999   2/2     Running   1          67m
    
  13. Go!Go!Go!

    Create an example PVC to see if claiming works:

    [jan@jan quobyte-k8s-helm]$ cat example-pvc.yaml 
    kind: PersistentVolumeClaim
    apiVersion: v1
    metadata:
      name: quobyte-csi-test
    spec:
      accessModes:
      - ReadWriteOnce
      resources:
        requests:
          storage: 1Gi
      storageClassName: quobyte-rf3
  14. Apply it to your Kubernetes cluster:
    [jan@jan quobyte-k8s-helm]$ kubectl apply -f example-pvc.yaml 
    persistentvolumeclaim/quobyte-csi-test created
    [jan@jan quobyte-k8s-helm]$ kubectl get pvc
    NAME               STATUS   VOLUME                                     CAPACITY   ACCESS MODES   STORAGECLASS   AGE
    quobyte-csi-test   Bound    pvc-8da51d22-2400-49d3-ba73-dfdc4e97b8be   1Gi        RWO            quobyte-rf3    7s
    [jan@jan quobyte-k8s-helm]$ kubectl apply -f example-pvc.yaml
  15. Quobyte view

    Switch back to your storage cluster and see what happened:

    deploy@smallscale-coreserver0:~$ qmgmt volume list
    WARNING: Existing session cookie was no longer valid and had to be deleted.
    WARNING: Could not fetch credentials from environment 
    Username: jan-quobyte
    Password: 
    Name                                      Tenant     Logical Usage  File Count  Configuration  S3 buckets  Mirrored From  /     
    pvc-8da51d22-2400-49d3-ba73-dfdc4e97b8be  My Tenant  0 bytes        -           BASE           -           -              -
  16. As you can see the Volume is getting created and usable from Kubernetes now!

Talk to Us

Quobyte can do a lot more for you than what you’ve seen so far.

To find out what, contact us to set up a quick demo.