Documentation

    PLEASE NOTE: This document applies to v0.9 version and not to the latest release v1.0

    Documentation for other releases can be found by using the version selector in the left bottom of any doc page.

    NFS Server CRD

    NFS Server can be created and configured using the nfsservers.nfs.rook.io custom resource definition (CRD). Please refer to the user guide walk-through for complete instructions. This page will explain all the available configuration options on the NFS CRD.

    Sample

    The parameters to configure the NFS CRD are demonstrated in the example below which is followed by a table that explains the parameters in more detail.

    Below is a very simple example that shows sharing a volume (which could be hostPath, cephFS, cephRBD, googlePD, EBS, etc.) using NFS, without any client or per export based configuration.

    For a PersistentVolumeClaim named googlePD-claim, which has Read/Write permissions and no squashing, the NFS CRD instance would look like the following:

    apiVersion: nfs.rook.io/v1alpha1
    kind: NFSServer
    metadata:
      name: nfs-vol
      namespace: rook
    spec:
      replicas: 1
      exports:
      - name: nfs-share
        server:
          accessMode: ReadWrite
          squash: none
        persistentVolumeClaim:
          claimName: googlePD-claim
    

    Settings

    The table below explains in detail each configuration option that is available in the NFS CRD.

    Parameter Description Default
    replicas The number of NFS daemon to start 1
    exports Parameters for creating an export <empty>
    exports.name Name of the volume being shared <empty>
    exports.server NFS server configuration <empty>
    exports.server.accessMode Volume access modes (Reading and Writing) for the share (Valid options are ReadOnly, ReadWrite and none) ReadWrite
    exports.server.squash This prevents root users connected remotely from having root privileges (valid options are none, rootId, root and all) none
    exports.server.allowedClients Access configuration for clients that can consume the NFS volume <empty>
    exports.server.allowedClients.name Name of the host/hosts <empty>
    exports.server.allowedClients.clients The host or network to which the export is being shared. Valid entries for this field are host names, IP addresses, netgroups, and CIDR network addresses. <empty>
    exports.server.allowedClients.accessMode Reading and Writing permissions for the client* (valid options are same as exports.server.accessMode) ReadWrite
    exports.server.allowedClients.squash Squash option for the client* (valid options are same as exports.server.squash) none
    exports.persistentVolumeClaim The PVC that will serve as the backing volume to be exported by the NFS server. Any PVC is allowed, such as host paths, CephFS, Ceph RBD, Google PD, Amazon EBS, etc.. <empty>
    exports.persistentVolumeClaim.claimName Name of the PVC <empty>

    *note: if exports.server.allowedClients.accessMode and exports.server.allowedClients.squash options are specified, exports.server.accessMode and exports.server.squash are overridden respectively.

    Description for volumes.allowedClients.squash valid options are:

    1. none (No user id squashing is performed)
    2. rootId (uid 0 and gid 0 are squashed to the anonymous uid and anonymous gid)
    3. root (uid 0 and gid of any value are squashed to the anonymous uid and anonymous gid)
    4. all (All users are squashed)

    The volume that needs to be exported by NFS must be attached to NFS server pod via PVC. Examples of volume that can be attached are Host Path, AWS Elastic Block Store, GCE Persistent Disk, CephFS, RBD etc. The limitations of these volumes also apply while they are shared by NFS. The limitation and other details about these volumes can be found here.

    Examples

    This section contains some examples for more advanced scenarios and configuration options.

    Single volume exported for access by multiple clients

    This example shows how to share a volume with different options for different clients accessing the share. The EBS volume (represented by a PVC) will be exported by the NFS server for client access as /nfs-share (note that this PVC must already exist). The following client groups are allowed to access this share:

    • group1 with IP address 172.17.0.5 will be given Read Only access with the root user squashed.
    • group2 includes both the network range of 172.17.0.5/16 and a host named serverX. They will all be granted Read/Write permissions with no user squash.
    apiVersion: nfs.rook.io/v1alpha1
    kind: NFSServer
    metadata:
      name: nfs-vol
      namespace: rook
    spec:
      replicas: 1
      exports:
      - name: nfs-share
        server:
          allowedClients:
          - name: group1
            clients: 172.17.0.5
            accessMode: ReadOnly
            squash: root
          - name: group2
            clients:
            - 172.17.0.0/16
            - serverX
            accessMode: ReadWrite
            squash: none
        persistentVolumeClaim:
          claimName: ebs-claim
    

    Multiple volumes

    This section provides an example of how to share multiple volumes from one NFS server. These volumes can all be different types (e.g., Google PD and Ceph RBD). Below we will share an Amazon EBS volume as well as a CephFS volume, using differing configuration for the two:

    • The EBS volume is named share1 and is available for all clients with Read Only access and no squash.
    • The CephFS volume is named share2 and is available for all clients with Read/Write access and no squash.
    apiVersion: nfs.rook.io/v1alpha1
    kind: NFSServer
    metadata:
      name: nfs-multi-vol
      namespace: rook
    spec:
      replicas: 1
      exports:
      - name: share1
        server:
          allowedClients:
          - name: ebs-host
            clients: all
            accessMode: ReadOnly
            squash: none
        persistentVolumeClaim:
          claimName: ebs-claim
      - name: share2
        server:
          allowedClients:
          - name: ceph-host
            clients: all
            accessMode: ReadWrite
            squash: none
        persistentVolumeClaim:
          claimName: cephfs-claim