Container Service for Kubernetes:Use volumes

Usage notes

OSS and NAS volumes are suitable for different use scenarios. The following table describes the details:

Each volume type has specific limitations and guidelines, and they may also incur associated resource costs. For more information, see the following topics:

• OSS volumes: OSS volumes, Mount a statically provisioned OSS volume

• NAS volumes: NAS volumes, Mount a statically provisioned NAS volume

Use OSS volumes

1. Use the following sample code to create an OSS volume.

   For more information, see Mount a statically provisioned OSS volume.

   apiVersion: v1
   kind: Secret
   metadata:
     name: oss-secret
     namespace: argo
   stringData:
     akId: <yourAccessKey ID> # Replace with the actual AccessKey ID.
     akSecret: <yourAccessKey Secret> # Replace with the actual AccessKey Secret.
   ---
   apiVersion: v1
   kind: PersistentVolume
   metadata:
     name: pv-oss
     namespace: argo
     labels:
       alicloud-pvname: pv-oss
   spec:
     capacity:
       storage: 5Gi
     accessModes:
       - ReadWriteMany
     persistentVolumeReclaimPolicy: Retain
     csi:
       driver: ossplugin.csi.alibabacloud.com
       volumeHandle: pv-oss   # Specify the name of the persistent volume (PV).
       nodePublishSecretRef:
         name: oss-secret
         namespace: argo
       volumeAttributes:
         bucket: <your bucket name> # Replace with the actual bucket name.
         url: "oss-<your region id>-internal.aliyuncs.com" # Replace <your region id> with the region ID of OSS. For example, the region ID of China (Beijing) is oss-cn-beijing-internal.aliyuncs.com.
         otherOpts: "-o max_stat_cache_size=0 -o allow_other -o multipart_size=30 -o parallel_count=20" # -o max_stat_cache_size=0
         path: "/"  # Mount the root directory of the bucket. You can also set this parameter to mount a subdirectory under the bucket, such as path: "testdir/testdir1".
   ---
   apiVersion: v1
   kind: PersistentVolumeClaim
   metadata:
     name: pvc-oss
     namespace: argo
   spec:
     accessModes:
       - ReadWriteMany
     resources:
       requests:
         storage: 5Gi
     selector:
       matchLabels:
         alicloud-pvname: pv-oss

   Optional parameter

   You can configure custom parameters in the -o *** -o *** format for the OSS volume. Example: -o umask=022 -o max_stat_cache_size=0 -o allow_other.

   Parameter	Description
   umask	Modifies the permissions for ossfs accessing files. For example, if you set umask=022, the permissions for ossfs files will change to 755. Files uploaded through OSS SDK or console have a default permission of 640 in ossfs. Therefore, we recommend that you specify the umask parameter if you want to split the read and write permissions.
   max_stat_cache_size	The maximum number of files whose metadata can be cached. Metadata caching can accelerate ls operations. However, if you modify files by using methods such as OSS SDKs, console, and ossutil, the cached metadata of the files is not synchronously updated. As a result, the cached metadata becomes outdated, and the results of ls operations may be inaccurate.
   allow_other	Allows other users to access the mounted directory. However, these users cannot access the files in the directory.

   For more information about other parameters, see Options supported by ossfs.

2. Use the following YAML template to create a workflow that uses a volume:

   apiVersion: argoproj.io/v1alpha1
   kind: Workflow
   metadata:
     generateName: volumes-existing-
     namespace: argo
   spec:
     entrypoint: volumes-existing-example
     volumes:
     # Pass the existing volume workdir to the volumes-existing-example template.
     # The syntax follows the same structure as Kubernetes pod specifications.
     - name: workdir
       persistentVolumeClaim:
         claimName: pvc-oss
   
     templates:
     - name: volumes-existing-example
       steps:
       - - name: generate
           template: whalesay
       - - name: print
           template: print-message
   
     - name: whalesay
       container:
         image: mirrors-ssl.aliyuncs.com/busybox:latest
         command: [sh, -c]
         args: ["echo generating message in volume; echo hello world | tee /mnt/vol/hello_world.txt"]
         volumeMounts:
         - name: workdir
           mountPath: /mnt/vol
   
     - name: print-message
       container:
         image: mirrors-ssl.aliyuncs.com/alpine:latest
         command: [sh, -c]
         args: ["echo getting message from volume; find /mnt/vol; cat /mnt/vol/hello_world.txt"]
         volumeMounts:
         - name: workdir
           mountPath: /mnt/vol

Use NAS volumes

1. Use the following YAML template to create a NAS volume.

   For more information, see Mount a statically provisioned NAS volume.

   apiVersion: v1
   kind: PersistentVolume
   metadata:
     name: pv-nas
     namespace: argo
     labels:
       alicloud-pvname: pv-nas
   spec:
     capacity:
       storage: 100Gi
     accessModes:
       - ReadWriteMany
     csi:
       driver: nasplugin.csi.alibabacloud.com
       volumeHandle: pv-nas   # Specify the name of the PV.
       volumeAttributes:
         server: "<your nas filesystem id>.cn-beijing.nas.aliyuncs.com"
         path: "/"
     mountOptions:
     - nolock,tcp,noresvport
     - vers=3
   ---
   kind: PersistentVolumeClaim
   apiVersion: v1
   metadata:
     name: pvc-nas
     namespace: argo
   spec:
     accessModes:
       - ReadWriteMany
     resources:
       requests:
         storage: 100Gi
     selector:
       matchLabels:
         alicloud-pvname: pv-nas

2. Use the following YAML template to mount and use a NAS volume in the workflow:

   apiVersion: argoproj.io/v1alpha1
   kind: Workflow
   metadata:
     generateName: volumes-existing-
     namespace: argo
   spec:
     entrypoint: volumes-existing-example
     volumes:
     # Pass the existing volume workdir to the volumes-existing-example template.
     # The syntax follows the same structure as Kubernetes pod specifications.
     - name: workdir
       persistentVolumeClaim:
         claimName: pvc-nas
   
     templates:
     - name: volumes-existing-example
       steps:
       - - name: generate
           template: whalesay
       - - name: print
           template: print-message
   
     - name: whalesay
       container:
         image: mirrors-ssl.aliyuncs.com/busybox:latest
         command: [sh, -c]
         args: ["echo generating message in volume; echo hello world | tee /mnt/vol/hello_world.txt"]
         volumeMounts:
         - name: workdir
           mountPath: /mnt/vol
   
     - name: print-message
       container:
         image: mirrors-ssl.aliyuncs.com/alpine:latest
         command: [sh, -c]
         args: ["echo getting message from volume; find /mnt/vol; cat /mnt/vol/hello_world.txt"]
         volumeMounts:
         - name: workdir
           mountPath: /mnt/vol