Backup Azure Blob Storage content to secondary region

Question

Pulumi · Accepted Answer

Backing up Azure Blob Storage content to a secondary region helps to ensure data durability and availability in case of regional failures or disasters. In this Pulumi TypeScript program, we will create two Azure Storage accounts, one in a primary region and another in a secondary region. Then, we will use Azure Blob Storage's built-in asynchronous replication feature called Geo-Redundant Storage (GRS) to automatically replicate the blobs from the primary storage account to the secondary storage account in a different region.

Here's how we can accomplish this task:

1. Create a primary Azure Storage Account with the GRS replication option.
2. Create a secondary Azure Storage Account in a different region with the GRS replication option.
3. Enable the replication feature on the primary storage account, which will take care of backing up the data to the secondary storage account.

The `azure-native.storage.StorageAccount` resource is used here because it provides the capabilities to create a Storage Account with various geo-redundancy options, such as GRS.

Let's go through the code to achieve this:

```typescript
import * as pulumi from "@pulumi/pulumi";
import * as azure_native from "@pulumi/azure-native";

// Replace these variables with the appropriate location for your primary and secondary regions
const primaryRegion = "East US";
const secondaryRegion = "West US";

// Create a primary storage account with GRS for geo-redundant storage
const primaryStorageAccount = new azure_native.storage.StorageAccount("primaryStorageAccount", {
    // This defaults to 'StorageV2' (general-purpose v2), which supports GRS
    kind: "StorageV2",
    sku: {
        name: "Standard_GRS", // 'GRS' stands for Geo-Redundant Storage
    },
    resourceGroupName: "myResourceGroup", // Replace with the name of your resource group
    location: primaryRegion,
});

// Create a secondary storage account in a different region
// We also use GRS here as a redundancy strategy to protect against regional unavailability
const secondaryStorageAccount = new azure_native.storage.StorageAccount("secondaryStorageAccount", {
    kind: "StorageV2",
    sku: {
        name: "Standard_GRS", // 'GRS' stands for Geo-Redundant Storage
    },
    resourceGroupName: "myResourceGroup", // Replace with the name of your resource group
    location: secondaryRegion,
});

// Export the primary and secondary account names
export const primaryStorageAccountName = primaryStorageAccount.name;
export const secondaryStorageAccountName = secondaryStorageAccount.name;
```

Explanation of the code:

- We import the necessary Pulumi packages to interact with Azure.
- We define our primary and secondary regions. It's essential to select regions supported by Azure and far enough apart to provide the required geographic redundancy.
- We create two instances of `StorageAccount`, one for the primary region and the other for the secondary region. Both use the `Standard_GRS` SKU, which enables Geo-Redundant Storage.
- The kind of the storage account is set to 'StorageV2' which is a general-purpose v2 storage account and supports features like GRS.
- We specify the resource group name, which should be created beforehand in each region to hold the corresponding storage account.
- The `location` property refers to the Azure region in which the storage account will be created, respectively for each account.
- We export the storage account names so that they can be retrieved after the deployment is completed. This allows you to confirm that the resources were created and reference them later if necessary.

After deploying this Pulumi program, you will have two storage accounts with Geo-Redundant Storage enabled, which means the content from the primary account will automatically be replicated to the secondary account across regions.

Remember to replace `myResourceGroup` with your own resource group's name where you want your storage accounts to reside. To run this Pulumi program, you will need to install Pulumi, set up the Azure provider, and have the appropriate permissions to create resources within your Azure subscription.