Initail commit

.stestr.conf

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+[DEFAULT]
+test_path=./unit_tests
+top_dir=./

.zuul.yaml

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+- project:
+    templates:
+      - openstack-python3-ussuri-jobs
+      - openstack-cover-jobs

README.md

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+# Overview
+
+The cinder charm is the Openstack block storage (i.e: Volume) service, whereas the cinder-nfs charm works as a subordinate of cinder, implementing a NFS backend.
+
+# Usage
+
+## Configuration
+
+This section covers common and/or important configuration options. See file `config.yaml` for the full list of options, along with their descriptions and default values.
+
+### `nfs-shares`
+
+A list of nfs shares that NFS driver should attempt to provision new Cinder volumes into
+
+Multiple nfs shares can be provided, each on its own line, in a format of `<host>:<share path>`
+```
+  192.168.1.200:/storage
+  192.168.1.201:/storage
+```
+
+The content will be written to /etc/cinder/nfs_shares by default or the file specified in nfs-shares-config option
+
+### `nfs-shares-config`
+
+The file that contain a list of NFS shares.  Cinder-volume will read this file to get its NFS backend detail
+
+
+### `nfs-mount-options`
+
+Specify mount options. See section of the NFS man page for details.
+
+
+## Deployment
+
+This charm's primary use is as a backend for the cinder charm. To do so, add a relation betweeen both charms:
+
+```
+  juju add-relation cinder-nfs:storage-backend cinder:storage-backend
+```
+
+# Developing
+
+Create and activate a virtualenv with the development requirements:
+```
+  virtualenv -p python3 venv
+  source venv/bin/activate
+  pip3 install -r requirements.txt
+  pip3 install -r test-requirements.txt
+```
+
+# Documentation
+
+The OpenStack Charms project maintains two documentation guides:
+
+* [OpenStack Charm Guide][cg]: for project information, including development
+  and support notes
+* [OpenStack Charms Deployment Guide][cdg]: for charm usage information
+
+# Bugs
+
+Please report bugs on [Launchpad][lp-bugs-charm-cinder-netapp].
+
+[cg]: https://docs.openstack.org/charm-guide
+[cdg]: https://docs.openstack.org/project-deploy-guide/charm-deployment-guide
+[lp-bugs-charm-cinder-netapp]: https://bugs.launchpad.net/charm-cinder-nfs/+filebug

build-requirements.txt

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+# NOTES(lourot):
+# * We don't install charmcraft via pip anymore because it anyway spins up a
+#   container and scp the system's charmcraft snap inside it. So the charmcraft
+#   snap is necessary on the system anyway.
+# * `tox -e build` successfully validated with charmcraft 1.2.1
+
+cffi==1.14.6; python_version < '3.6'  # cffi 1.15.0 drops support for py35.

charmcraft.yaml

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+type: charm
+parts:
+  charm:
+    after:
+      - update-certificates
+    charm-python-packages:
+      # NOTE(lourot): see
+      # * https://github.com/canonical/charmcraft/issues/551
+      # * https://github.com/canonical/charmcraft/issues/632
+      - setuptools < 58
+    build-packages:
+      - git
+  update-certificates:
+    plugin: nil
+    # See https://github.com/canonical/charmcraft/issues/658
+    override-build: |
+      apt update
+      apt install -y ca-certificates
+      update-ca-certificates      
+bases:
+  - build-on:
+      - name: ubuntu
+        channel: "20.04"
+        architectures:
+          - amd64
+    run-on:
+      - name: ubuntu
+        channel: "20.04"
+        architectures: [amd64, s390x, ppc64el, arm64]
+      - name: ubuntu
+        channel: "22.04"
+        architectures: [amd64, s390x, ppc64el, arm64]

config.yaml

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+options:
+  volume-backend-name:
+    type: string
+    default: 'cinder-nfs'
+    description: |-
+      Service backend name to present to Cinder
+      If left empty, application's name will be used as backend name
+
+  nfs-shares:
+    type: string
+    default: ''
+    description: |-
+      'A list of nfs shares in format of <host>:<share>, each on their
+      own line, to which the driver should attempt to provision new
+      Cinder volumes into.
+
+      # example
+      192.168.1.200:/storage
+      192.168.1.201:/storage
+
+      Above content will be writtent to /etc/cinder/nfs_shares or the file
+      specified in nfs-shares-config option'
+
+  nfs-shares-config:
+    type: string
+    default: "/etc/cinder/nfs_shares"
+    description: |
+      The file name that contain a a list of nfs-shares
+
+  nfs-mount-point-base:
+    type: string
+    default: "/var/lib/cinder/nfs"
+    description: Directory where cinder-volume mounts all NFS shares.
+
+  nfs-mount-options:
+    type: string
+    default: ''
+    description: |-
+      Mount options passed to NFS client.
+      See NFS man page for available mount options
+
+  nfs-mount-attempts:
+    type: int
+    default: 3
+    description: |-
+       Number of attempts to mount NFS shares before raising an error.
+       At least one attempt will be made to mount an NFS share, regardless
+       of the value specified.
+  nfs-snapshot-support:
+    type: boolean
+    default: False
+    description: |
+       Enable support for snapshots on the NFS driver. 
+       Platforms using libvirt <1.2.7 will encounter issues with this feature.
+
+  nfs-qcow2-volumes:
+    type: boolean
+    default: False
+    description: |
+       Create volumes as QCOW2 files rather than raw files.
+
+  nfs-sparsed-volumes:
+    type: boolean
+    default: True
+    description: |
+       'Create volumes as sparsed files which take no space. 
+       If set to False volume is created as regular file. In such case volume 
+       creation takes a lot of time.'

copyright

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+Format: http://dep.debian.net/deps/dep5/
+
+Files: *
+Copyright: Copyright 2021-2022, Canonical Ltd., All Rights Reserved.
+License: Apache License 2.0
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
+ .
+     http://www.apache.org/licenses/LICENSE-2.0
+ .
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.

metadata.yaml

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+name: cinder-nfs
+summary:  NFS integration for OpenStack Block Storage
+maintainer: OpenStack Charmers <openstack-charmers@lists.ubuntu.com>
+description: |
+ Cinder is the block storage service for the Openstack project.
+ .
+ This charm provides a NFS backend for Cinder
+tags:
+  - openstack
+  - storage
+  - file-servers
+  - misc
+series:
+  - focal
+  - jammy
+subordinate: true
+provides:
+  storage-backend:
+    interface: cinder-backend
+    scope: container
+requires:
+  juju-info:
+    interface: juju-info
+    scope: container

osci.yaml

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+- project:
+    templates:
+      - charm-unit-jobs
+    vars:
+      needs_charm_build: true
+      build_type: charmcraft
+      charm_build_name: cinder-nfs

pip.sh

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+#!/usr/bin/env bash
+#
+# This file is managed centrally by release-tools and should not be modified
+# within individual charm repos.  See the 'global' dir contents for available
+# choices of tox.ini for OpenStack Charms:
+#     https://github.com/openstack-charmers/release-tools
+#
+# setuptools 58.0 dropped the support for use_2to3=true which is needed to
+# install blessings (an indirect dependency of charm-tools).
+#
+# More details on the beahvior of tox and virtualenv creation can be found at
+# https://github.com/tox-dev/tox/issues/448
+#
+# This script is wrapper to force the use of the pinned versions early in the
+# process when the virtualenv was created and upgraded before installing the
+# depedencies declared in the target.
+pip install 'pip<20.3' 'setuptools<50.0.0'
+pip "$@"

rename.sh

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+#!/bin/bash
+charm=$(grep "charm_build_name" osci.yaml | awk '{print $2}')
+echo "renaming ${charm}_*.charm to ${charm}.charm"
+echo -n "pwd: "
+pwd
+ls -al
+echo "Removing bad downloaded charm maybe?"
+if [[ -e "${charm}.charm" ]];
+then
+    rm "${charm}.charm"
+fi
+echo "Renaming charm here."
+mv ${charm}_*.charm ${charm}.charm

requirements.txt

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+# requirements
+ops
+git+https://github.com/juju/charm-helpers.git#egg=charmhelpers
+git+https://opendev.org/openstack/charm-ops-openstack#egg=ops_openstack
+git+https://opendev.org/openstack/charm-ops-interface-tls-certificates#egg=interface_tls_certificates

src/charm.py

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+#!/usr/bin/env python3
+# Copyright 2022 Canonical Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#  http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""Charm for deploying and maintaining the Cinder NFS backend driver."""
+
+from ops.main import main
+from ops.model import ActiveStatus, BlockedStatus
+from ops_openstack.plugins.classes import CinderStoragePluginCharm
+
+import os
+import io
+import shutil
+
+
+def _check_config(charm_config):
+    """
+    These checks are in addition to the parent class checks
+    for MANDATORY_CONFIG.
+    """
+    if not charm_config["nfs-shares"]:
+        return BlockedStatus("NFS shares not configured")
+
+    return ActiveStatus("Unit is ready")
+
+
+class CharmCinderNFSCharm(CinderStoragePluginCharm):
+    """Charm the Cinder NFS driver."""
+
+    PACKAGES = ["cinder-common"]
+
+    MANDATORY_CONFIG = [
+        "nfs-shares",
+        "nfs-shares-config",
+        "volume-backend-name",
+        "nfs-mount-point-base",
+        "nfs-mount-attempts",
+        "nfs-snapshot-support",
+        "nfs-qcow2-volumes",
+        "nfs-sparsed-volumes",
+    ]
+
+    def on_config(self, event):
+        status = _check_config(self.framework.model.config)
+        if not isinstance(status, ActiveStatus):
+            self.unit.status = status
+            return
+
+        super().on_config(event)
+
+    def cinder_configuration(self, charm_config):
+        options = []
+        nfs_shares = ""
+
+        volumedriver = "cinder.volume.drivers.nfs.NfsDriver"
+        options.append(("volume_driver", volumedriver))
+
+        for key, value in charm_config.items():
+            # if volume-backend-name is empty, set to application name
+            if key == "volume-backend-name" and not value:
+                value = self.framework.model.app.name
+
+            if key == "nfs-shares":
+                nfs_shares = os.linesep.join([s for s in value.splitlines() if s])
+                buff = io.StringIO(nfs_shares)
+                continue
+
+            if key == "nfs-shares-config":
+                path = value
+                with open(path, "w+") as f:
+                    print(buff.getvalue(), file=f)
+                os.chmod(path, 0o640)
+                shutil.chown(path, user="root", group="cinder")
+
+            options.append((key.replace("-", "_"), value))
+
+        return options
+
+
+if __name__ == "__main__":
+    main(CharmCinderNFSCharm)

test-requirements.txt

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+# This file is managed centrally.  If you find the need to modify this as a
+# one-off, please don't.  Intead, consult #openstack-charms and ask about
+# requirements management in charms via bot-control.  Thank you.
+charm-tools>=2.4.4
+coverage>=3.6
+mock>=1.2
+flake8>=4.0.1
+stestr>=2.2.0
+requests>=2.18.4
+psutil
+# oslo.i18n dropped py35 support
+oslo.i18n<4.0.0
+git+https://github.com/openstack-charmers/zaza.git#egg=zaza
+git+https://github.com/openstack-charmers/zaza-openstack-tests.git#egg=zaza.openstack
+pytz    # workaround for 14.04 pip/tox
+pyudev  # for ceph-* charm unit tests (not mocked?)

tests/bundles/focal-ussuri.yaml

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+series: focal
+variables:
+  openstack-origin: &openstack-origin distro
+machines:
+  '0':
+local_overlay_enabled: false
+relations:
+  - - cinder:storage-backend
+    - cinder-three-par:storage-backend
+applications:
+  cinder:
+    charm: ch:cinder
+    num_units: 1
+    options:
+      openstack-origin: *openstack-origin
+      block-device: None
+      overwrite: "true"
+      ephemeral-unmount: /mnt
+    to:
+      - '0'
+  cinder-three-par:
+    charm: ../../cinder-three-par.charm
+    options:
+      hpe3par-debug: False
+      driver-type: fc
+      san-ip: 127.0.0.1
+      san-login: admin
+      san-password: password
+      hpe3par-username: admin
+      hpe3par-password: password
+      hpe3par-api-url: https://127.0.0.1:8080/api/v1/
+      hpe3par-cpg: cpgname
+      hpe3par_cpg_snap: cpgname
+      use-multipath-for-image-xfer: True
+      enforce-multipath-for-image-xfer: True

tests/tests.yaml

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+charm_name: cinder-three-par
+
+target_deploy_status:
+  cinder:
+    workload-status: blocked
+    workload-status-message-prefix: "Missing relations:"
+
+tests:
+  - tests.tests_cinder_three_par.CinderThreeParTest
+
+configure: []
+gate_bundles:
+  - focal-ussuri
+smoke_bundles:
+  - focal-ussuri
+dev_bundles:
+  - focal-ussuri

tests/tests_cinder_nfs.py

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+#!/usr/bin/env python3
+
+# Copyright 2021 Canonical Ltd.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+
+import zaza.model
+from zaza.openstack.charm_tests.test_utils import BaseCharmTest
+
+
+class CinderNFSTest(BaseCharmTest):
+    """Encapsulate Cinder NFS tests."""
+
+    def test_cinder_config(self):
+        """Test that configuration options match our expectations."""
+        zaza.model.run_on_leader(
+            "cinder",
+            "sudo cp /etc/cinder/cinder.conf /tmp/",
+        )
+        zaza.model.block_until_oslo_config_entries_match(
+            "cinder",
+            "/tmp/cinder.conf",
+            {
+                "cinder-nfs": {
+                    # sanity test a few common params
+                    "volume_backend_name": ["cinder-nfs"],
+                    "nfs_share_config": ["/etc/cinder/nfs_shares"],
+                    "nfs_mount_point_base": ["/var/lib/cinder/nfs"],
+                    "nfs_mount_options": [""],
+                    "nfs_mount_attempt": [3],
+                }
+            },
+            timeout=2,
+        )

tox.ini

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+# Operator charm (with zaza): tox.ini
+[tox]
+envlist = pep8,py3
+skipsdist = True
+# NOTE: Avoid build/test env pollution by not enabling sitepackages.
+sitepackages = False
+# NOTE: Avoid false positives by not skipping missing interpreters.
+skip_missing_interpreters = False
+# NOTES:
+# * We avoid the new dependency resolver by pinning pip < 20.3, see
+#   https://github.com/pypa/pip/issues/9187
+# * Pinning dependencies requires tox >= 3.2.0, see
+#   https://tox.readthedocs.io/en/latest/config.html#conf-requires
+# * It is also necessary to pin virtualenv as a newer virtualenv would still
+#   lead to fetching the latest pip in the func* tox targets, see
+#   https://stackoverflow.com/a/38133283
+# * It is necessary to declare setuptools as a dependency otherwise tox will
+#   fail very early at not being able to load it. The version pinning is in
+#   line with `pip.sh`.
+requires = pip < 20.3
+           virtualenv < 20.0
+           setuptools < 50.0.0
+           tox < 4.0.0
+# NOTE: https://wiki.canonical.com/engineering/OpenStack/InstallLatestToxOnOsci
+minversion = 3.2.0
+[testenv]
+setenv = VIRTUAL_ENV={envdir}
+         PYTHONHASHSEED=0
+         CHARM_DIR={envdir}
+install_command =
+  pip install {opts} {packages}
+commands = stestr run --slowest {posargs}
+allowlist_externals =
+    git
+    add-to-archive.py
+    bash
+    charmcraft
+    rename.sh
+passenv = HOME TERM CS_* OS_* TEST_*
+deps = -r{toxinidir}/test-requirements.txt
+[testenv:py35]
+deps =
+basepython = python3.5
+# python3.5 is irrelevant on a focal+ charm.
+commands = /bin/true
+[testenv:py36]
+basepython = python3.6
+deps = -r{toxinidir}/requirements.txt
+       -r{toxinidir}/test-requirements.txt
+[testenv:py37]
+basepython = python3.7
+deps = -r{toxinidir}/requirements.txt
+       -r{toxinidir}/test-requirements.txt
+[testenv:py38]
+basepython = python3.8
+deps = -r{toxinidir}/requirements.txt
+       -r{toxinidir}/test-requirements.txt
+[testenv:py39]
+basepython = python3.9
+deps = -r{toxinidir}/requirements.txt
+       -r{toxinidir}/test-requirements.txt
+[testenv:py310]
+basepython = python3.10
+deps = -r{toxinidir}/requirements.txt
+       -r{toxinidir}/test-requirements.txt
+[testenv:py3]
+basepython = python3
+deps = -r{toxinidir}/requirements.txt
+       -r{toxinidir}/test-requirements.txt
+[testenv:pep8]
+basepython = python3
+deps = -r{toxinidir}/requirements.txt
+       -r{toxinidir}/test-requirements.txt
+commands = flake8 {posargs} src unit_tests tests
+[testenv:cover]
+# Technique based heavily upon
+# https://github.com/openstack/nova/blob/master/tox.ini
+basepython = python3
+deps = -r{toxinidir}/requirements.txt
+       -r{toxinidir}/test-requirements.txt
+setenv =
+    {[testenv]setenv}
+    PYTHON=coverage run
+commands =
+    coverage erase
+    stestr run --slowest {posargs}
+    coverage combine
+    coverage html -d cover
+    coverage xml -o cover/coverage.xml
+    coverage report
+[coverage:run]
+branch = True
+concurrency = multiprocessing
+parallel = True
+source =
+    .
+omit =
+    .tox/*
+    */charmhelpers/*
+    unit_tests/*
+[testenv:venv]
+basepython = python3
+commands = {posargs}
+[testenv:build]
+basepython = python3
+deps = -r{toxinidir}/build-requirements.txt
+commands =
+    charmcraft clean
+    charmcraft -v pack 
+    {toxinidir}/rename.sh
+[testenv:func-noop]
+basepython = python3
+commands =
+    functest-run-suite --help
+[testenv:func]
+basepython = python3
+commands =
+    functest-run-suite --keep-model
+[testenv:func-smoke]
+basepython = python3
+commands =
+    functest-run-suite --keep-model --smoke
+[testenv:func-dev]
+basepython = python3
+commands =
+    functest-run-suite --keep-model --dev
+[testenv:func-target]
+basepython = python3
+commands =
+    functest-run-suite --keep-model --bundle {posargs}
+[flake8]
+# Ignore E902 because the unit_tests directory is missing in the built charm.
+ignore = E402,E226,E902
+

unit_tests/__init__.py

@@ -0,0 +1,16 @@
+# Copyright 2022 Canonical Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#  http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import ops.testing
+ops.testing.SIMULATE_CAN_CONNECT = True

unit_tests/test_charm.py

@@ -0,0 +1,104 @@
+# Copyright 2022 Canonical Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#  http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import unittest
+import json
+
+from ops.model import Relation, BlockedStatus, ActiveStatus
+from ops.testing import Harness
+from src.charm import CharmCinderNFSCharm
+
+
+class TestCharm(unittest.TestCase):
+    maxDiff = None
+
+    def setUp(self):
+        self.harness = Harness(CharmCinderNFSCharm)
+        self.addCleanup(self.harness.cleanup)
+        self.harness.begin()
+        self.harness.set_leader(True)
+        self.model = self.harness.model
+        self.storage_backend = self.harness.add_relation("storage-backend", "cinder")
+        self.harness.add_relation_unit(self.storage_backend, "cinder/0")
+        self.harness.update_config(
+            {
+                "volume-backend-name": "cinder-nfs",
+                "nfs-shares": "172.18.18.61:/srv/test",
+                "nfs-mount-point-base": "/var/lib/cinder/nfs",
+                "nfs-mount-options": "vers=3",
+                "nfs-mount-attempts": 3,
+            }
+        )
+
+    def _get_sub_conf(self):
+        rel = self.model.get_relation("storage-backend", 0)
+        self.assertIsInstance(rel, Relation)
+        rdata = rel.data[self.model.unit]
+        rdata = json.loads(rdata["subordinate_configuration"])
+        return dict(
+            rdata["cinder"]["/etc/cinder/cinder.conf"]["sections"]["cinder-nfs"]
+        )
+
+    def test_backend_name_in_data(self):
+        rel = self.model.get_relation("storage-backend", 0)
+        rdata = rel.data[self.model.unit]
+        self.assertEqual(rdata["backend_name"], "cinder-nfs")
+
+    def test_config_changed(self):
+        self.harness.update_config(
+            {
+                "nfs-mount-point-base": "/var/lib/cinder/nfsmount",
+                "nfs-mount-options": "vers=4.1,proto=tcp,retry=4,",
+                "nfs-mount-attempts": 4,
+            }
+        )
+        self.assertEqual(
+            self._get_sub_conf(),
+            {
+                "volume_driver": "cinder.volume.drivers.nfs.NfsDriver",
+                "nfs_mount_point_base": "/var/lib/cinder/nfsmount",
+                "nfs_mount_options": "vers=4.1,proto=tcp,retry=4,",
+                "nfs_mount_attempts": 4,
+            },
+        )
+
+    def test_blocked_status(self):
+        self.harness.update_config(unset=["nfs-shares"])
+        self.assertIsInstance(self.harness.charm.unit.status, BlockedStatus)
+        message = self.harness.charm.unit.status.message
+        self.assertIn("NFS shares not configured", message)
+
+    def test_status_with_mandatory_config(self):
+        self.assertEqual(self.harness.charm.unit.status.message, "Unit is ready")
+        self.assertIsInstance(self.harness.charm.unit.status, ActiveStatus)
+        self.harness.update_config(
+            unset=["nfs-shares-config"],
+        )
+        self.assertEqual(
+            self.harness.charm.unit.status.message,
+            "Missing option(s): nfs-shares-config",
+        )
+        self.assertIsInstance(self.harness.charm.unit.status, BlockedStatus)
+
+    def test_volume_backend_name_config(self):
+        self.assertEqual(self._get_sub_conf().get("volume_backend_name"), "cinder-nfs")
+
+        self.harness.update_config(
+            {
+                "volume-backend-name": "test-backend",
+            }
+        )
+        self.assertEqual(
+            self._get_sub_conf().get("volume_backend_name"), "test-backend"
+        )