Implement NFS multi backend support

The NFS implementation based off cinder_nfs_client
does not support per cinder backend configuration,
separating NFS mounts per backend.
This fix removes cinder_nfs_client in favor of
fully supporting multi cinder backends over the
cinder_backends stanza.

Closes-Bug #1657203

Change-Id: I817ff372c2d58e999a89496fce3d25dc617216f0

defaults/main.yml

@@ -205,16 +205,6 @@ cinder_quota_backup_gigabytes: 1000
 # cinder_backend_lvm_inuse: True if current host has an lvm backend
 cinder_backend_lvm_inuse: '{{ (cinder_backends|default("")|to_json).find("lvm") != -1 }}'
 
-## Define nfs information for cinder. When the cinder_nfs_client dictionary is defined,
-## it will enable nfs shares.  The value ``nfs_shares_config`` is the path on the disk
-## where the NFS export will live. The ``shares`` value is a list of dictionaries that
-## must have the IP address of the NFS server and the location where the export will be.
-# cinder_nfs_client:
-#   nfs_shares_config: /etc/cinder/nfs_shares
-#   shares:
-#     - ip: "127.0.0.1"
-#       share: "/vol/cinder"
-
 ## Policy vars
 # Provide a list of access controls to update the default policy.json with. These changes will be merged
 # with the access controls in the default policy.json. E.g.

doc/source/configure-cinder.rst

@@ -30,15 +30,29 @@ Edit ``/etc/openstack_deploy/openstack_user_config.yml`` and configure
 the NFS client on each storage node if the NetApp backend is configured to use
 an NFS storage protocol.
 
-#. Add the ``cinder_backends`` stanza (which includes
-   ``cinder_nfs_client``) under the ``container_vars`` stanza for
-   each storage node:
+#. For each storage node, add one ``cinder_backends`` block underneath
+   the a new ``container_vars`` section. ``container_vars`` are used to
+   allow container/host individualized configuration. Each cinder back end
+   is defined with a unique key. For example, ``nfs-volume1``.
+   This later represents a unique cinder backend and volume type.
 
    .. code-block:: yaml
 
        container_vars:
          cinder_backends:
-           cinder_nfs_client:
+           nfs-volume1:
+
+#. Configure the appropriate cinder volume backend name:
+
+   .. code::
+
+      volume_backend_name: NFS_VOLUME1
+
+#. Configure the appropriate cinder NFS driver:
+
+   .. code::
+
+      volume_driver: cinder.volume.drivers.nfs.NfsDriver
 
 #. Configure the location of the file that lists shares available to the
    block storage service. This configuration file must include
@@ -46,21 +60,43 @@ an NFS storage protocol.
 
    .. code-block:: yaml
 
-       nfs_shares_config: SHARE_CONFIG
+       nfs_shares_config: FILENAME_NFS_SHARES
 
-   Replace ``SHARE_CONFIG`` with the location of the share
-   configuration file. For example, ``/etc/cinder/nfs_shares``.
+   Replace ``FILENAME_NFS_SHARES`` with the location of the share
+   configuration file. For example, ``/etc/cinder/nfs_shares_volume1``.
+
+#. Define mount options for the NFS mount. For example:
+
+   .. code::
+
+      nfs_mount_options: "rsize=65535,wsize=65535,timeo=1200,actimeo=120"
 
 #. Configure one or more NFS shares:
 
    .. code-block:: yaml
 
        shares:
-          - { ip: "NFS_HOST", share: "NFS_SHARE" }
+          - { ip: "HOSTNAME", share: "PATH_TO_NFS_VOLUME" }
 
-   Replace ``NFS_HOST`` with the IP address or hostname of the NFS
-   server, and the ``NFS_SHARE`` with the absolute path to an existing
-   and accessible NFS share.
+   Replace ``HOSTNAME`` with the IP address or hostname of the NFS
+   server, and the ``PATH_TO_NFS_VOLUME`` with the absolute path to an
+   existing and accessible NFS share (excluding the IP address or hostname).
+
+The following is a full configuration example of a cinder NFS backend
+named NFS1. The cinder playbooks will automatically add a custom
+``volume-type`` and ``nfs-volume1`` as in this example:
+
+   .. code::
+
+     container_vars:
+       cinder_backends:
+         nfs-volume1:
+           volume_backend_name: NFS_VOLUME1
+           volume_driver: cinder.volume.drivers.nfs.NfsDriver
+           nfs_shares_config: /etc/cinder/nfs_shares_volume1
+           nfs_mount_options: "rsize=65535,wsize=65535,timeo=1200,actimeo=120"
+           shares:
+           - { ip: "1.2.3.4", share: "/vol1" }
 
 Backup
 ~~~~~~
@@ -407,9 +443,9 @@ each storage node that will use it.
 
    .. code-block:: yaml
 
-       nfs_shares_config: SHARE_CONFIG
+       nfs_shares_config: FILENAME_NFS_SHARES
 
-   Replace ``SHARE_CONFIG`` with the location of the share
+   Replace ``FILENAME_NFS_SHARES`` with the location of the share
    configuration file. For example, ``/etc/cinder/nfs_shares``.
 
 #. Configure the server:

releasenotes/notes/cinder-nfs-multibackend-df133e8fff374da4.yaml

@@ -0,0 +1,5 @@
+---
+upgrade:
+  - The global override ``cinder_nfs_client`` is replaced
+    in favor of fully supporting multi backends
+    configuration via the cinder_backends stanza.

tasks/cinder_post_install.yml

@@ -68,10 +68,13 @@
 - name: Create nfs shares export file
   template:
     src: nfs_shares.j2
-    dest: "{{ cinder_nfs_client.nfs_shares_config }}"
+    dest: "{{ item.value.nfs_shares_config }}"
+  with_dict: "{{ cinder_backends }}"
   when:
-    - cinder_nfs_client is defined
+    - item.value.nfs_shares_config is defined
     - inventory_hostname in groups['cinder_volume']
+  tags:
+    - cinder-nfs
 
 - name: Drop sudoers file
   template:

templates/cinder.conf.j2

@@ -102,9 +102,6 @@ enabled_backends={% for backend in cinder_backends|dictsort %}{{ backend.0 }}{%
 {% for key, value in backend_section.1.items() if key != 'extra_volume_types' %}
 {{ key }}={{ value }}
 {% endfor %}
-{% if cinder_nfs_client is defined %}
-nfs_shares_config={{ cinder_nfs_client.nfs_shares_config }}
-{% endif %}
 
 {% endfor %}
 {% endif %}

templates/nfs_shares.j2

@@ -1,5 +1,4 @@
 # {{ ansible_managed }}
-
-{% for share in cinder_nfs_client.shares %}
+{% for share in item.value.shares %}
 {{ share.ip }}:{{ share.share }}
 {% endfor %}