CSI Proxy

CSI Proxy is a binary that exposes a set of gRPC APIs around storage operations over named pipes in Windows. A container, such as CSI node plugins, can mount the named pipes depending on operations it wants to exercise on the host and invoke the APIs.

Each named pipe will support a specific version of an API (e.g. v1alpha1, v2beta1) that targets a specific area of storage (e.g. disk, volume, file, SMB, iSCSI).

Overview

CSI drivers are recommended to be deployed as containers. Node plugin containers need to run with privileges to perform storage related operations. However, Windows does not support privileged containers currently. With CSIProxy, the node plugins can now be deployed as unprivileged pods that use the proxy to perform privileged storage operations on the node. Kubernetes administrators will need to install and maintain csi-proxy.exe on all Windows nodes in a manner similar to kubelet.exe.

Compatibility

Recommended K8s Version: 1.18

Feature status

CSI-proxy is currently in Alpha status

Installation

csi-proxy.exe can be installed and run as binary or run as a Windows service on each Windows node. See the following as an example to run CSI Proxy as a web service.

    $flags = "-windows-service -log_file=\etc\kubernetes\logs\csi-proxy.log -logtostderr=false"
    sc.exe create csiproxy binPath= "\etc\kubernetes\node\bin\csi-proxy.exe $flags"
    sc.exe failure csiproxy reset= 0 actions= restart/10000
    sc.exe start csiproxy

If you are using kube-up to start a Windows cluster, node startup script will automatically run csi-proxy as a service. For GKE 1.18+, csi-proxy will be installed automatically.

Usage

Command line options

• --kubelet-csi-plugins-path: This is the prefix path of the Kubelet plugin directory in the host file system (C:\var\lib\kubelet is used by default).

• --kubelet-pod-path: This is the prefix path of the kubelet pod directory in the host file system (C:\var\lib\kubelet is used by default).

Setup for CSI Driver Deployment

Deploy and start csiproxy.exe on all Windows hosts in the cluster. Next, the named pipes can be mounted in a CSI node plugin DaemonSet YAML in the following manner:

kind: DaemonSet
apiVersion: apps/v1
metadata:
  name: csi-storage-node-win
spec:
  selector:
    matchLabels:
      app: csi-driver-win
  template:
    metadata:
      labels:
        app: csi-driver-win
    spec:
      serviceAccountName: csi-node-sa
      tolerations:
      - key: "node.kubernetes.io/os"
        operator: "Equal"
        value: "win1809"
        effect: "NoSchedule"
      nodeSelector:
        kubernetes.io/os: windows
      containers:
        - name: csi-driver-registrar
          image: gke.gcr.io/csi-node-driver-registrar:win-v1
          args:
            - "--v=5"
            - "--csi-address=unix://C:\\csi\\csi.sock"
            - "--kubelet-registration-path=C:\\var\\lib\\kubelet\\plugins\\pd.csi.storage.gke.io\\csi.sock"
          env:
            - name: KUBE_NODE_NAME
              valueFrom:
                fieldRef:
                  fieldPath: spec.nodeName
          volumeMounts:
            - name: plugin-dir
              mountPath: C:\csi
            - name: registration-dir
              mountPath: C:\registration
        - name: csi-driver
          image: org/csi-driver:win-v1
          args:
            - "--v=5"
            - "--endpoint=unix:/csi/csi.sock"
          volumeMounts:
            - name: kubelet-dir
              mountPath: C:\var\lib\kubelet
            - name: plugin-dir
              mountPath: C:\csi
            - name: csi-proxy-disk-pipe
              mountPath: \\.\pipe\csi-proxy-disk-v1alpha1
            - name: csi-proxy-volume-pipe
              mountPath: \\.\pipe\csi-proxy-volume-v1alpha1
            - name: csi-proxy-filesystem-pipe
              mountPath: \\.\pipe\csi-proxy-filesystem-v1alpha1
            - name: csi-proxy-iscsi-pipe
              mountPath: \\.\pipe\csi-proxy-iscsi-v1alpha1
      volumes:
        - name: csi-proxy-disk-pipe
          hostPath:
            path: \\.\pipe\csi-proxy-disk-v1alpha1
            type: ""
        - name: csi-proxy-volume-pipe
          hostPath:
            path: \\.\pipe\csi-proxy-volume-v1alpha1
            type: ""
        - name: csi-proxy-filesystem-pipe
          hostPath:
            path: \\.\pipe\csi-proxy-filesystem-v1alpha1
            type: ""
        - name: csi-proxy-iscsi-pipe
          hostPath:
            path: \\.\pipe\csi-proxy-iscsi-v1alpha1
            type: ""
        - name: registration-dir
          hostPath:
            path: C:\var\lib\kubelet\plugins_registry\
            type: Directory
        - name: kubelet-dir
          hostPath:
            path: C:\var\lib\kubelet\
            type: Directory
        - name: plugin-dir
          hostPath:
            path: C:\var\lib\kubelet\plugins\csi.org.io\
            type: DirectoryOrCreate

Community, discussion, contribution, and support

Learn how to engage with the Kubernetes community on the community page.

You can reach the maintainers of this project at:

• Slack channel
• Mailing list

Supported CSI Drivers

• SMB CSI Driver

• Azure Disk CSI Driver

• Azure File CSI Driver

• Google Compute Engine Persistent Disk CSI Driver

Code of conduct

Participation in the Kubernetes community is governed by the Kubernetes Code of Conduct.