Introduction

What is Democratic-CSI?

Democratic-CSI implements the CSI (Container Storage Interface) specifications providing storage for various container orchestration systems (ie: Kubernetes, Nomad, OpenShift).

The current focus is providing storage via iSCSI or NFS from ZFS-based storage systems, predominantly TrueNAS / FreeNAS and ZoL on Ubuntu.
The current drivers implement the depth and breadth of the csi specifications, so you have access to resizing, snapshots, clones, etc functionality.

What can Democratic-CSI offer?

Several implementations of CSI drivers
▶️ freenas-nfs (manages zfs datasets to share over nfs)
▶️ freenas-iscsi (manages zfs zvols to share over iscsi)
▶️ freenas-smb (manages zfs datasets to share over smb)
▶️ freenas-api-nfs experimental use with SCALE only (manages zfs datasets to share over nfs)
▶️ freenas-api-iscsi experimental use with SCALE only (manages zfs zvols to share over iscsi)
▶️ freenas-api-smb experimental use with SCALE only (manages zfs datasets to share over smb)
▶️ zfs-generic-nfs (works with any ZoL installation...ie: Ubuntu)
▶️ zfs-generic-iscsi (works with any ZoL installation...ie: Ubuntu)
▶️ zfs-local-ephemeral-inline (provisions node-local zfs datasets)
▶️ synology-iscsi experimental (manages volumes to share over iscsi)
▶️ lustre-client (crudely provisions storage using a shared lustre share/directory for all volumes)
▶️ nfs-client (crudely provisions storage using a shared nfs share/directory for all volumes)
▶️ smb-client (crudely provisions storage using a shared smb share/directory for all volumes)
▶️ node-manual (allows connecting to manually created smb, nfs, lustre, and iscsi volumes, see sample PVs in the examples directory)

Development
▶️ Framework for developing CSI drivers

If you have any interest in providing a CSI driver, simply open an issue to discuss. The project provides an extensive framework to build and making it relatively easy to implement new drivers.

Community Guides

Using TrueNAS to provide persistent storage for Kubernetes
Migrating from NFS-client-provisioner to democratic-CSI
Migrating between storage classes using Velero

Installation

Predominantly 3 prerequisites are needed:

• Nodes preperation (ie: Kubernetes cluster nodes)
• Storage server preperation
• Deployment of the driver into the cluster (helm chart provided with sample values.yaml)

🔧 Node preperation

Alright, you have chosen your driver. Let's start by configuring the prerequisites for your Node.
You can choose to use either NFS or iSCSI or both.

NFS configuration

---

RHEL / CentOS

sudo yum install -y nfs-utils

Ubuntu / Debian

sudo apt-get install -y nfs-common

iSCSI configuration

---

RHEL / CentOS
Install the following system packages:

sudo yum install -y lsscsi iscsi-initiator-utils sg3_utils device-mapper-multipath

Enable multipathing:

sudo mpathconf --enable --with_multipathd y

Ensure that iscsid and multipathd are running:

sudo systemctl enable iscsid multipathd && sudo systemctl start iscsid multipathd

Start and enable iSCSI:

sudo systemctl enable iscsi && sudo systemctl start iscsi

Ubuntu / Debian
Install the following system packages:

sudo apt-get install -y open-iscsi lsscsi sg3-utils multipath-tools scsitools

Multipathing

Multipath is supported for the iSCSI-based drivers. Simply setup multipath to your liking and set multiple portals in the config as appropriate.
NOTE: If you are running Kubernetes with Rancher/RKE please see the following:
Support host iscsi simultaneously with kubelet iscsi (pvc)

Add the mutlipath configuration:

sudo tee /etc/multipath.conf <<-'EOF'
defaults {
    user_friendly_names yes
    find_multipaths yes
}
EOF

Enable the multipath-tools service and restart to load the configuration:

sudo systemctl enable multipath-tools && sudo service multipath-tools restart

Ensure that open-iscsi and multipath-tools are enabled and running:

sudo systemctl status multipath-tools
sudo systemctl enable open-iscsi.service
sudo service open-iscsi start
sudo systemctl status open-iscsi

FreeNAS-SMB

---

If using with Windows based machines you may need to enable guest access (even if you are connecting with credentials)

Set-ItemProperty HKLM:\SYSTEM\CurrentControlSet\Services\LanmanWorkstation\Parameters AllowInsecureGuestAuth -Value 1 ; Restart-Service LanmanWorkstation -Force

ZFS-local-ephemeral-inline

---

This driver provisions node-local ephemeral storage on a per-pod basis. Each node should have an identically named ZFS pool created and avaialble to the driver.
NOTE: This is NOT the same thing as using the docker ZFS storage driver (although the same pool could be used). No other requirements are necessary. More regarding to this can be found here: Pod Inline Volume Support

🔧 Storage server preperation

Storage server preperation depends slightly on which driver you are using. The recommended version of FreeNAS / TrueNAS is 12.0-U2 or higher, however the driver should work with much older versions as well.

TrueNAS / FreeNAS (freenas-nfs, freenas-iscsi, freenas-smb, freenas-api-nfs, freenas-api-iscsi, freenas-api-smb)

API without SSH

---

Configuration templates can be found HERE
The various freenas-api-* drivers are currently EXPERIMENTAL and can only be used with SCALE 21.08+. Fundamentally these drivers remove the need for ssh connections and do all operations entirely with the TrueNAS api. With that in mind, any ssh/shell/etc requirements below can be safely ignored. Also note the following known issues:

• Additional middleware changes to support Democratic CSI use of native API
• TrueNAS Scale 21.08 - Could not log into all portals
• Pure api based truenas driver (ssh dependency removed)

Continue configuration

API with SSH

---

Configuration templates can be found HERE

Continue configuration

Service configuration

Ensure the following services are configured, running and starting automatically:

SSH configuration

---

• When creating a custom user (e.g., CSI):

  • Ensure ZSH, BASH, or SH is set as shell, CSH gives false errors due to quoting (also applicable when using root)
     

  • Ensure that user has passwordless sudo privileges:
    NOTE: This could get reset by FreeNAS if you alter the user via the GUI later

    • On TrueNAS CORE 12.0-u3 or higher, open the Shell:

      cli
      

      After you enter the truenas cli and are at that prompt:

      account user query select=id,username,uid,sudo_nopasswd
      

      find the id of the user you want to update (note, this is distinct from the uid)

      account user update id=<id> sudo=true
      

      account user update id=<id> sudo_nopasswd=true
      

      (Optional) If you want to enable passwordless authentication via CLI:

      account user update id=<id> password_disabled=true
      

      Exit the CLI by pressing ctrl-d

    • On other versions add the user to the sudoers file:

      visudo
      

      <username> ALL=(ALL) NOPASSWD:ALL
      

      Confirm sudoers file is appropriate:

      cat /usr/local/etc/sudoers
      

  • CSI has a homefolder, this is used to store its SSH Public Key  

  • Add the user to wheel or create/use a group that will be used for permissions later on

NFS configuration

---

• Bind the network interface to the NFS service
• It is recommended to use NFS 3

iSCSI configuration

---

NOTE: (Fixed in 12.0-U2+) when using the FreeNAS API concurrently, the /etc/ctl.conf file on the server can become invalid, some sample scripts are provided in the contrib directory to clean things up ie:
Copy the script to the server and directly and run - ./ctld-config-watchdog-db.sh | logger -t ctld-config-watchdog-db.sh &
Please read the scripts and set the variables appropriate for your server.

• Ensure you have pre*emptively created portals, initatior groups, auths
  • Make note of the respective IDs (the true ID may not reflect what is visible in the UI)
  • IDs can be visible by clicking the the Edit link and finding the ID in the browser address bar
  • Optionally you may use the following to retrieve appropiate IDs:
    • curl --header "Accept: application/json" --user root:<password> 'http(s)://<ip>/api/v2.0/iscsi/portal'
    • curl --header "Accept: application/json" --user root:<password> 'http(s)://<ip>/api/v2.0/iscsi/initiator'
    • curl --header "Accept: application/json" --user root:<password> 'http(s)://<ip>/api/v2.0/iscsi/auth'

SMB configuration

---

• Bind the network interface to the SMB service

ZoL (zfs-generic-nfs, zfs-generic-iscsi)

---

Ensure ssh and zfs is installed on the nfs/iscsi server and that you have installed targetcli.

sudo yum install targetcli -y

sudo apt-get -y install targetcli-fb

Synology (synology-iscsi)

---

Ensure iSCSI Manager has been installed and is generally setup/configured.

🔧 YAML Values configuration

---

Instruct Democratic-CSI to use sudo by uncommenting the following in your configuration template:

zfs:
  cli:
    sudoEnabled: true

As you read at the Storage server preperation, YAML configuration comes in two flavours. With and without API configuration.

Starting with TrueNAS CORE 12 it is also possible to use an apiKey instead of the user/root password for the HTTP connection. The apiKey can be generated by clicking on the Settings icon -> API Keys -> ADD

Issues to review:
ixsystems NAS-108519
ixsystems NAS-108520
ixsystems NAS-108521
ixsystems NAS-108522
ixsystems NAS-107219

🔧 Helm Installation

---

Copy proper example Values file from the examples:
API without SSH
API with SSH

Add the Democratic-CSI Helm repository:

helm search repo democratic-csi/

Update your Helm repository to get latest charts:

helm repo update

Helm V3

---

Install Democratic-CSI with your configured values. Helm V3 requires that you --create-namespace

helm install zfs-nfs democratic-csi/democratic-csi --values truenas-isci.yaml --create-namespace democratic-csi

Update/Upgrade Values:

helm upgrade <name> democratic-csi/democratic-csi --values <freenas-*>.yaml --namespace <namespace>

Helm V2

---

Install Democratic-CSI with your configured values.

helm upgrade \
--install \
--values freenas-nfs.yaml \
--namespace democratic-csi \
zfs-nfs democratic-csi/democratic-csi

On non standard Kubelet paths

Some distrobutions, such as minikube and microk8s use a non-standard kubelet path. In such cases it is ecessary to provide a new kubelet host path, microk8s example below:

microk8s helm upgrade \
  --install \
  --values freenas-nfs.yaml \
  --set node.kubeletHostPath="/var/snap/microk8s/common/var/lib/kubelet"  \
  --namespace democratic-csi \
  zfs-nfs democratic-csi/democratic-csi

• microk8s - /var/snap/microk8s/common/var/lib/kubelet
• pivotal - /var/vcap/data/kubelet

OpenShift

Democratic-CSI generally works fine with openshift. Some special parameters need to be set with helm (support added in chart version 0.6.1):

NOTE: for sure required

--set node.rbac.openshift.privileged=true

--set node.driver.localtimeHostPath=false

NOTE: Unlikely, but in special circumstances may be required

--set controller.rbac.openshift.privileged=true

Nomad

Democratic-CSI works with Nomad in a functioning but limted capacity. See the Nomad docs for details.

🔧 Multiple Deployments

You may install multiple deployments of each/any driver. It requires the following:

• Use a new helm release name for each deployment
• Make sure you have a unique csiDriver.name in the values file
• Use unqiue names for your storage classes (per cluster)
• Use a unique parent dataset (ie: don't try to use the same parent across deployments or clusters)

🔧 Snapshot Support

External-snapshotter CRD
Install beta (v1.17+) CRDs (one per cluster):

kubectl apply -f snapshot.storage.k8s.io_volumesnapshotclasses.yaml

kubectl apply -f snapshot.storage.k8s.io_volumesnapshotcontents.yaml

kubectl apply -f snapshot.storage.k8s.io_volumesnapshots.yaml

External-snapshotter Controller
Install snapshot controller (once per cluster):
Add --namespace references to your need.

kubectl apply -f rbac-snapshot-controller.yaml

kubectl apply -f setup-snapshot-controller.yaml

Install Democratic-CSI with volumeSnapshotClasses appropriatly defined.

Volume-snapshots
External-snapshotter Usage
Democratic-CSI Issue

🔧 Migrating from freenas-provisioner and freenas-iscsi-provisioner

It is possible to migrate all volumes from the non-csi freenas provisioners to Democratic-CSI.

Copy the contrib/freenas-provisioner-to-democratic-csi.sh script from the project to your workstation. Read the script in detail, and edit the variables to your needs to start migrating!

🏆 Sponsors

A special shout out to the wonderful sponsors of this project!

Related

Freenas provisioner
Freenas iSCSI provisioner
Welcome TrueNAS Core container storageprovider Truenas CSI
Synology CSI