MinIO Operator

MinIO is a Kubernetes-native high performance object store with an S3-compatible API. The MinIO Kubernetes Operator supports deploying MinIO Tenants onto private and public cloud infrastructures ("Hybrid" Cloud).

This README provides a high level description of the MinIO Operator and quickstart instructions. See https://docs.min.io/minio/k8s/ for complete documentation on the MinIO Operator.

Table of Contents

• Architecture
  • MinIO Console
  • MinIO Operator and kubectl Plugin
• Deploy the MinIO Operator and Create a Tenant
  • Prerequisites
  • Procedure

Architecture

Each MinIO Tenant represents an independent MinIO Object Store within the Kubernetes cluster. The following diagram describes the architecture of a MinIO Tenant deployed into Kubernetes:

MinIO provides multiple methods for accessing and managing the MinIO Tenant:

MinIO Console

The MinIO Console provides a graphical user interface (GUI) for interacting with MinIO Tenants. The MinIO Operator installs and configures the Console for each tenant by default.

Administrators of MinIO Tenants can perform a variety of tasks through the Console, including user creation, policy configuration, and bucket replication. The Console also provides a high level view of Tenant health, usage, and healing status.

For more complete documentation on using the MinIO Console, see the MinIO Console Github Repository.

MinIO Operator and kubectl Plugin

The MinIO Operator extends the Kubernetes API to support deploying MinIO-specific resources as a Tenant in a Kubernetes cluster.

The MinIO kubectl minio plugin wraps the Operator to provide a simplified interface for deploying and managing MinIO Tenants in a Kubernetes cluster through the kubectl command line tool.

Deploy the MinIO Operator and Create a Tenant

This procedure installs the MinIO Operator and creates a 4-node MinIO Tenant for supporting object storage operations in a Kubernetes cluster.

Prerequisites

Kubernetes 1.19 or Later

Starting with Operator v4.0.0, MinIO requires Kubernetes version 1.19.0 or later. Previous versions of the Operator supported Kubernetes 1.17.0 or later. You must upgrade your Kubernetes cluster to 1.19.0 or later to use Operator v4.0.0+.

This procedure assumes the host machine has kubectl installed and configured with access to the target Kubernetes cluster.

MinIO Tenant Namespace

MinIO supports no more than one MinIO Tenant per Namespace. The following kubectl command creates a new namespace for the MinIO Tenant.

kubectl create namespace minio-tenant-1

The MinIO Operator Console supports creating a namespace as part of the Tenant Creation procedure.

Tenant Storage Class

The MinIO Kubernetes Operator automatically generates Persistent Volume Claims (PVC) as part of deploying a MinIO Tenant.

The plugin defaults to creating each PVC with the default Kubernetes Storage Class. If the default storage class cannot support the generated PVC, the tenant may fail to deploy.

MinIO Tenants require that the StorageClass sets volumeBindingMode to WaitForFirstConsumer. The default StorageClass may use the Immediate setting, which can cause complications during PVC binding. MinIO strongly recommends creating a custom StorageClass for use by PV supporting a MinIO Tenant.

The following StorageClass object contains the appropriate fields for supporting a MinIO Tenant using MinIO DirectCSI-managed drives:

apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
    name: direct-csi-min-io
provisioner: kubernetes.io/no-provisioner
volumeBindingMode: WaitForFirstConsumer

Tenant Persistent Volumes

The MinIO Operator generates one Persistent Volume Claim (PVC) for each volume in the tenant plus two PVC to support collecting Tenant Metrics and logs. The cluster must have sufficient Persistent Volumes that meet the capacity requirements of each PVC for the tenant to start correctly. For example, deploying a Tenant with 16 volumes requires 18 (16 + 2). If each PVC requests 1TB capacity, then each PV must also provide at least 1TB of capacity.

MinIO recommends using the MinIO DirectCSI Driver to automatically provision Persistent Volumes from locally attached drives. This procedure assumes MinIO DirectCSI is installed and configured.

For clusters which cannot deploy MinIO DirectCSI, use Local Persistent Volumes. The following example YAML describes a local persistent volume:

The following YAML describes a local PV:

apiVersion: v1
kind: PersistentVolume
metadata:
   name: <PV-NAME>
spec:
   capacity:
      storage: 1Ti
   volumeMode: Filesystem
   accessModes:
   - ReadWriteOnce
   persistentVolumeReclaimPolicy: Retain
   storageClassName: local-storage
   local:
      path: </mnt/disks/ssd1>
   nodeAffinity:
      required:
         nodeSelectorTerms:
         - matchExpressions:
            - key: kubernetes.io/hostname
              operator: In
              values:
              - <NODE-NAME>

Replace values in brackets <VALUE> with the appropriate value for the local drive.

You can estimate the number of PVC by multiplying the number of minio server pods in the Tenant by the number of drives per node. For example, a 4-node Tenant with 4 drives per node requires 16 PVC and therefore 16 PV.

MinIO strongly recommends using the following CSI drivers for creating local PV to ensure best object storage performance:

• MinIO DirectCSI
• Local Persistent Volume

Procedure

1) Install the MinIO Operator

Run the following commands to install the MinIO Operator and Plugin using the Kubernetes krew plugin manager:

kubectl krew update
kubectl krew install minio

See the krew installation documentation for instructions on installing krew.

Run the following command to verify installation of the plugin:

kubectl minio version

As an alternative to krew, you can download the kubectl-minio plugin from the Operator Releases Page. Download the kubectl-minio package appropriate for your operating system and extract the contents as kubectl-minio. Set the kubectl-minio binary to be executable (e.g. chmod +x) and place it in your system PATH.

For example, the following code downloads the latest stable version of the MinIO Kubernetes Plugin and installs it to the system $PATH. The example assumes a Linux operating system:

wget -qO- https://github.com/minio/operator/releases/latest/download/kubectl-minio_linux_amd64.zip | sudo bsdtar -xvf- -C /usr/local/bin
sudo chmod +x /usr/local/bin/kubectl-minio

Run the following command to verify installation of the plugin:

kubectl minio version

Run the following command to initialize the Operator:

kubectl minio init

Run the following command to verify the status of the Operator:

kubectl get pods -n minio-operator

The output resembles the following:

NAME                              READY   STATUS    RESTARTS   AGE
console-6b6cf8946c-9cj25          1/1     Running   0          99s
minio-operator-69fd675557-lsrqg   1/1     Running   0          99s

The console-* pod runs the MinIO Operator Console, a graphical user interface for creating and managing MinIO Tenants.

The minio-operator-* pod runs the MinIO Operator itself.

2) Access the Operator Console

Run the following command to create a local proxy to the MinIO Operator Console:

kubectl minio proxy -n minio-operator

The output resembles the following:

kubectl minio proxy
Starting port forward of the Console UI.

To connect open a browser and go to http://localhost:9090

Current JWT to login: TOKENSTRING

Open your browser to the provided address and use the JWT token to log in to the Operator Console.

Click + Create Tenant to open the Tenant Creation workflow.

3) Build the Tenant Configuration

The Operator Console Create New Tenant walkthrough builds out a MinIO Tenant. The following list describes the basic configuration sections.

• Name - Specify the Name, Namespace, and Storage Class for the new Tenant.

  The Storage Class must correspond to a Storage Class that corresponds to Local Persistent Volumes that can support the MinIO Tenant.

  The Namespace must correspond to an existing Namespace that does not contain any other MinIO Tenant.

  Enable Advanced Mode to access additional advanced configuration options.

• Tenant Size - Specify the Number of Servers, Number of Drives per Server, and Total Size of the Tenant.

  The Resource Allocation section summarizes the Tenant configuration based on the inputs above.

  Additional configuration inputs may be visible if Advanced Mode was enabled in the previous step.

• Preview Configuration - summarizes the details of the new Tenant.

After configuring the Tenant to your requirements, click Create to create the new tenant.

The Operator Console displays credentials for connecting to the MinIO Tenant. You must download and secure these credentials at this stage. You cannot trivially retrieve these credentials later.

You can monitor Tenant creation from the Operator Console.

4) Connect to the Tenant

Use the following command to list the services created by the MinIO Operator:

kubectl get svc -n NAMESPACE

Replace NAMESPACE with the namespace for the MinIO Tenant. The output resembles the following:

NAME                             TYPE            CLUSTER-IP        EXTERNAL-IP   PORT(S)      
minio                            LoadBalancer    10.104.10.9       <pending>     443:31834/TCP
minio-tenant-1-console           LoadBalancer    10.104.216.5      <pending>     9443:31425/TCP
minio-tenant-1-hl                ClusterIP       None              <none>        9000/TCP
minio-tenant-1-log-hl-svc        ClusterIP       None              <none>        5432/TCP
minio-tenant-1-log-search-api    ClusterIP       10.102.151.239    <none>        8080/TCP
minio-tenant-1-prometheus-hl-svc ClusterIP       None              <none>        9090/TCP

Applications internal to the Kubernetes cluster should use the minio service for performing object storage operations on the Tenant.

Administrators of the Tenant should use the minio-tenant-1-console service to access the MinIO Console and manage the Tenant, such as provisioning users, groups, and policies for the Tenant.

MinIO Tenants deploy with TLS enabled by default, where the MinIO Operator uses the Kubernetes certificates.k8s.io API to generate the required x.509 certificates. Each certificate is signed using the Kubernetes Certificate Authority (CA) configured during cluster deployment. While Kubernetes mounts this CA on Pods in the cluster, Pods do not trust that CA by default. You must copy the CA to a directory such that the update-ca-certificates utility can find and add it to the system trust store to enable validation of MinIO TLS certificates:

cp /var/run/secrets/kubernetes.io/serviceaccount/ca.crt /usr/local/share/ca-certificates/
update-ca-certificates

For applications external to the Kubernetes cluster, you must configure Ingress or a Load Balancer to expose the MinIO Tenant services. Alternatively, you can use the kubectl port-forward command to temporarily forward traffic from the local host to the MinIO Tenant.

License

Use of MinIO Operator is governed by the GNU AGPLv3 or later, found in the LICENSE file.

Explore Further

MinIO Hybrid Cloud Storage Documentation

• Deploy MinIO Operator on Kubernetes
• Deploy a MinIO Tenant using the MinIO Plugin
• Configure TLS/SSL for MinIO Tenants

Github Resources

• Examples for MinIO Tenant Settings
• Custom Hostname Discovery.
• Apply PodSecurityPolicy.
• Deploy MinIO Tenant with Console.
• Deploy MinIO Tenant with KES.
• Tenant API Documentation