Using kubernetes velero.io with clickhouse.altinity.com

Question

Pulumi · Accepted Answer

Velero is a tool used to back up and restore Kubernetes cluster resources and persistent volumes. It works by creating a Velero server instance within your Kubernetes cluster, which you then can use to manage backup operations. These backups can be stored in a cloud provider's object storage, such as AWS S3, Google Cloud Storage, or Azure Blob Storage.

ClickHouse, on the other hand, is an open-source column-oriented database management system that allows for generating analytical data reports in real-time. Altinity offers enterprise ClickHouse solutions and services, such as managed ClickHouse instances or support for ClickHouse deployments on Kubernetes.

To integrate Velero with a ClickHouse setup in Kubernetes, you would first need to set up Velero in your Kubernetes cluster and configure it to back up to a storage location that you've designated. Assuming you have a ClickHouse installation running on Kubernetes managed by Altinity, or you're using the ClickHouse Kubernetes operator from Altinity, you might want to ensure that your Velero installation includes appropriate backup hooks or scripts to properly handle the state of the ClickHouse databases during backup operations.

Here's a high-level TypeScript program using Pulumi and the Kubernetes provider to deploy Velero to a Kubernetes cluster with a storage location configured for AWS S3 (similar setups could be created for GCP or Azure). We will illustrate this with infrastructure as code, ensuring that we have a Kubernetes cluster to deploy these services in.

First, we're going to create a Kubernetes cluster, then install Velero along with its dependencies, and ensure it's configured correctly to back up ClickHouse data. Note that for this setup, we'll assume that you have the necessary cloud provider credentials configured in Pulumi and `kubectl` configured to communicate with your cluster.

Before you run this program, you must have Pulumi installed and configured with the appropriate cloud provider credentials—for AWS in this case. You'll also need to replace `bucketName` and `backupLocationConfig` with actual values suitable for your environment.

```typescript
import * as pulumi from "@pulumi/pulumi";
import * as aws from "@pulumi/aws";
import * as kubernetes from "@pulumi/kubernetes";

// Create an S3 bucket for Velero backups.
const backupsBucket = new aws.s3.Bucket("velero-backups", {
    acl: "private",
    forceDestroy: true, // Enable this to allow pulumi to delete bucket even if it contains objects. Exercise with caution.
});

// Create an IAM user for Velero.
const veleroUser = new aws.iam.User("velero", {});

// Attach policies to the user so it can access the bucket.
const accessPolicy = new aws.iam.Policy("access-policy", {
    policy: backupsBucket.arn.apply(arn => JSON.stringify({
        Version: "2012-10-17",
        Statement: [
            {
                Action: ["s3:GetObject", "s3:PutObject"],
                Effect: "Allow",
                Resource: `${arn}/*`,
            },
            {
                Action: ["s3:ListBucket"],
                Effect: "Allow",
                Resource: arn,
            },
        ],
    })),
});
new aws.iam.PolicyAttachment("access-policy-attachment", {
    users: [veleroUser.name],
    policyArn: accessPolicy.arn,
});

// Kubernetes cluster setup goes here (e.g., using EKS, AKS, GKE, etc.)
// This example assumes the `kubeconfig` is already configured.

// Configuration for the Velero Helm chart
const veleroChart = new kubernetes.helm.v3.Chart("velero", {
    chart: "velero",
    version: "2.23.6", // Ensure you use the correct chart version
    fetchOpts: { repo: "https://vmware-tanzu.github.io/helm-charts" },
    values: {
        configuration: {
            provider: "aws",
            backupStorageLocation: {
                name: "aws",
                bucket: backupsBucket.bucket,
                config: {
                    region: aws.config.region,
                },
            },
            volumeSnapshotLocation: {
                name: "aws",
                config: {
                    region: aws.config.region,
                },
            },
        },
        credentials: {
            useSecret: true,
            existingSecret: veleroUser.name,  // We will need to create a Kubernetes secret for this
        },
        // You need to set up serviceAccount.server.create to true, allowing it to manage cluster resources.
        serviceAccount: {
            server: {
                create: true,
            }
        },
        // In your real-world usage, the tolerations, nodeSelector, and affinity would depend on your cluster setup.
    },
});

// Export the name of the bucket
export const bucketName = backupsBucket.bucket;
```

This program sets up Velero in AWS, along with an S3 bucket for storing backups. When adapting this code, you should securely handle your IAM user credentials and possibly use more restricted IAM roles, depending on your organization's security practices.

The Helm chart configuration for Velero includes sections where you can specify your cloud provider and backup locations. Note that the actual backup process of ClickHouse data would depend on how ClickHouse is set up in your cluster, as you might need custom hooks or scripts to ensure consistency of backups.

In a real-world scenario, your Pulumi program would also include the logic to deploy ClickHouse, likely using the Helm chart provided by Altinity or your custom Kubernetes manifests. It is important to ensure that the data backup process managed by Velero is aware of ClickHouse's data and that proper backup hooks are in place to guarantee data consistency.

Please replace `chart`, `version`, and any `values` configurations to match the actual setup you require. The above is an example showing the structure and concepts but would need adjustments for a production setup.