Labeling Ondat Objects

For more information regarding the Ondat Label Sync feature, see our Kubernetes Object Sync reference page.

Label Syncing

The Ondat API Manager handles cases where information from objects in your Kubernetes Cluster needs to be synced to your Ondat cluster.

Label Syncing on PVCs

The below guide shows how to apply a label to your PVCs, and how these labels sync through to your Ondat Volumes. This operation is used often - for example it is used here to add replicas to an Ondat Volume.

Create a PVC, following the instructions here. When you create a PVC, Ondat automatically provisions an Ondat volume for it. An example PVC and Ondat volume can be seen below. Note the labels app=mysql and env=prod under Labelsin the PVC description and the VolumeAttributesof the Ondat Volume.

$ kubectl describe pvc/data-mysql-0
Name:          data-mysql-0
Namespace:     default
StorageClass:  storageos
Status:        Bound
Volume:        pvc-2e6339f0-96f9-4098-a388-149fd0daa14f
Labels:        app=mysql
               env=prod
Annotations:   pv.kubernetes.io/bind-completed: yes
               pv.kubernetes.io/bound-by-controller: yes
               storageos.com/storageclass: 572794ab-2d02-4fec-9aaf-43cd725f498e
               volume.beta.kubernetes.io/storage-provisioner: csi.storageos.com
...

$ storageos describe volume pvc-2e6339f0-96f9-4098-a388-149fd0daa14f -oyaml
id: 286fd3a6-c8f8-480a-b5e1-d16896db0c72
name: pvc-2e6339f0-96f9-4098-a388-149fd0daa14f
...
labels:
    app: mysql
    csi.storage.k8s.io/pv/name: pvc-2e6339f0-96f9-4098-a388-149fd0daa14f
    csi.storage.k8s.io/pvc/name: data-mysql-0
    csi.storage.k8s.io/pvc/namespace: default
    env: prod
    storageos.com/nocompress: "true"
    storageos.com/replicas: "0"
...

Now, apply a label to the PVC.

kubectl label pvc data-mysql-0 storageos.com/replicas=3

By using the Ondat CLI, you can verify that the label applied has been synced through to our Ondat volume and the replicas are all present.

$ storageos describe volume pvc-2e6339f0-96f9-4098-a388-149fd0daa14f -oyaml
id: 286fd3a6-c8f8-480a-b5e1-d16896db0c72
name: pvc-2e6339f0-96f9-4098-a388-149fd0daa14f
description: ""
attachedOn: 72b50fa0-d870-4d57-95fc-980cc41ab951
attachedOnName: worker5
attachmentType: host
nfs:
    exports: []
    serviceendpoint: ""
namespaceID: d4eb1a29-39e1-477f-b57c-1c264b797575
namespaceName: default
labels:
    app: mysql
    csi.storage.k8s.io/pv/name: pvc-2e6339f0-96f9-4098-a388-149fd0daa14f
    csi.storage.k8s.io/pvc/name: data-mysql-0
    csi.storage.k8s.io/pvc/namespace: default
    env: prod
    storageos.com/nocompress: "true"
    storageos.com/replicas: "3"
filesystem: ext4
sizeBytes: 5368709120
master:
    id: 836d8bbc-d356-4ad1-89d2-b1da7f6a4e47
    nodeID: 72b50fa0-d870-4d57-95fc-980cc41ab951
    nodeName: worker5
    health: online
    promotable: true
replicas:
  - id: 46d9ef46-7572-4b23-80c9-097b77c4f7a0
    nodeID: b812eb26-f59e-4867-824f-152acfa70968
    nodeName: worker4
    health: ready
    promotable: true
  - id: 7876164b-b2f0-4148-9688-6b154dfa073a
    nodeID: 52a98f1a-4d33-41e6-891a-6931052c4ba3
    nodeName: worker1
    health: ready
    promotable: true
  - id: 3987e698-68c9-4e8b-adee-16d0f424a106
    nodeID: d2b8ca25-4ffb-43ae-90cc-e1bc68be12ee
    nodeName: worker6
    health: ready
    promotable: true
createdAt: 2021-05-06T14:57:58Z
updatedAt: 2021-05-06T16:47:26Z
version: Mzg

Label Syncing on Nodes

Some Ondat functionality is set by labeling nodes - for example setting a node to “compute-only” mode, as demonstrated here.

Note labels on the node that will be labeled and on the Ondat node corresponding to that Kubernetes node.

$ kubectl describe node worker1 
Name:               worker1
Roles:              worker
Labels:             beta.kubernetes.io/arch=amd64
            beta.kubernetes.io/os=linux
            cattle.io/creator=norman
            kubernetes.io/arch=amd64
            kubernetes.io/hostname=worker1
            kubernetes.io/os=linux
            node-role.kubernetes.io/worker=true
Annotations:        csi.volume.kubernetes.io/nodeid: {"csi.storageos.com":"52a98f1a-4d33-41e6-891a-6931052c4ba3"}
            flannel.alpha.coreos.com/backend-data: {"VtepMAC":"06:7b:af:b9:a5:2b"}
            flannel.alpha.coreos.com/backend-type: vxlan
            flannel.alpha.coreos.com/kube-subnet-manager: true
            flannel.alpha.coreos.com/public-ip: 212.71.244.105
            node.alpha.kubernetes.io/ttl: 0
            projectcalico.org/IPv4IPIPTunnelAddr: 10.42.2.1
            rke.cattle.io/external-ip: 212.71.244.105
            rke.cattle.io/internal-ip: 192.168.152.238
            volumes.kubernetes.io/controller-managed-attach-detach: true
CreationTimestamp:  Thu, 06 May 2021 13:28:30 +0100
...

$ kubectl describe -n storageos pod storageos-daemonset-6q4g8 
Name:                 storageos-daemonset-6q4g8
Namespace:            storageos
Priority:             2000001000
Priority Class Name:  system-node-critical
Node:                 worker1/192.168.152.238
Start Time:           Thu, 06 May 2021 15:53:34 +0100
Labels:               app=storageos
              app.kubernetes.io/component=storageos-daemonset
              app.kubernetes.io/instance=example-ondat
              app.kubernetes.io/managed-by=storageos-operator
              app.kubernetes.io/name=storageos
              app.kubernetes.io/part-of=storageos
              controller-revision-hash=f5dcf577d
              kind=daemonset
              pod-template-generation=1
              storageos_cr=example-ondat
Annotations:          kubectl.kubernetes.io/default-logs-container: storageos
Status:               Running
IP:                   192.168.152.238
IPs:
  IP:           192.168.152.238

Now, apply the label to the node.

kubectl label node worker1 storageos.com/computeonly=true

The label has synced to the node and it has been set to compute-only mode.

$ storageos describe node worker1
ID                                      52a98f1a-4d33-41e6-891a-6931052c4ba3    
Name                                    worker1                                 
Health                                  online                                  
Addresses:                            
  Data Transfer address                 192.168.152.238:5703                    
  Gossip address                        192.168.152.238:5711                    
  Supervisor address                    192.168.152.238:5704                    
  Clustering address                    192.168.152.238:5710                    
Labels                                  beta.kubernetes.io/arch=amd64,          
                    beta.kubernetes.io/os=linux,            
                    cattle.io/creator=norman,               
                    kubernetes.io/arch=amd64,               
                    kubernetes.io/hostname=worker1,         
                    kubernetes.io/os=linux,                 
                    node-role.kubernetes.io/worker=true,    
                    storageos.com/computeonly=true