In the ever-evolving landscape of cloud computing, businesses are increasingly relying on cloud file storage solutions to ensure accessibility, scalability and data security. One crucial aspect of optimizing your cloud storage strategy is replication, which is set to help with your business continuity, disaster recovery, data migration and expansion by providing seamless, asynchronous replication for all your file shares—adding an extra layer of redundancy to your data.

Understanding replication

Replication is the process of duplicating data across multiple storage locations to ensure data availability, fault tolerance and reliability. This replication process involves creating and maintaining an identical copy of your file share in a different availability zone (AZ) within a multi-zone region (MZR), allowing for data access in the event of an AZ failure. The key objectives include improving data durability, minimizing downtime and enhancing overall system resilience.

Cross-region replication involves duplicating your data to a different MZR; this redundancy ensures that even if a region experiences downtime or a catastrophic event, your data remains accessible from another region. Cross-region replication serves as a robust disaster recovery (DR) strategy. In the event of a natural disaster, outage or any other unforeseen circumstance, your data remains intact and accessible.

When the initial replication is complete, any changes that are made on the source share are automatically replicated to the replica share on the target region in frequent intervals, asynchronously. The time between each replication event (recovery point objective, or RPO) on the replica share can be as low as one hour. The replica share on the target region is always available and you can fail over within the recovery time objective (RTO) of a minute or less. RTO ensures that your workloads that depend on the replica can use it quickly on a different region upon a disaster.

Cross-region replication plays a pivotal role in both disaster recovery and geo-migration strategies. In the event of an unforeseen disruption rendering the primary region inaccessible, cross-region replication facilitates a seamless failover to another region by utilizing a replica. This unplanned failover becomes imperative for maintaining business continuity during critical times.

Conversely, in the context of strategic geo migration, cross-region replication plays a crucial role in executing a planned relocation of your data to a different region. Businesses can achieve a seamless transfer with minimal downtime by creating a replica in the target region. This proactive approach ensures minimal disruption to ongoing operations, allowing for a systematic migration of the database.

How to create a cross-region replica

Creating a replica—be it in a different AZ within the same MZR as the file share or in a completely separate and different region—is fairly simple, and you can create and manage your replicas from UI, CLI, API or with Terraform. (Terraform support is expected in the first quarter of 2024.) The following steps will show you how to create a cross-region replica within the IBM Cloud console. It is assumed that you already created a file share that will be the source of your replica.

1. Within the VPC Infrastructure section in the IBM Cloud console, access the File storage shares subsection, which will show the list of your file shares. Go ahead and click on the file share you want to replicate, and it will take you to your share details page. In this example, I’m going to create a replica of ‘demo-share’:

2. On the Actions button within your file share details page, click on Create replica—this will open a new replica provisioning page:

3. The source share details will be pre-loaded on the replica provisioning page:

4. You can select a different AZ within the same region, or you can select a different AZ in a different MZR. In this example, I’m going to replicate from WDC2 to DAL1:

5. After you select the MZR and add a name for your replica, you will be asked to enter the IOPS for the replica share. Since this will be a replica, it is suggested that you keep the IOPS at the minimum as it will impact the replica share pricing:

6. Lastly, select the desired sync frequency (the time between each replication event) and click on Create file share:

Things to keep in mind when using cross-region replication

• Availability: This feature is available in all MZRs, but cross-region replication is restricted to the same geography. Cross-geography replication is not supported—refer to About file share replication for supported region pairs.
• Billing: The data transferred between regions (gigabytes transmitted) is charged at $0.02/GB/mo (data transferred price is the same in all target regions). Standard file share billing applies for the replica.
• Data residency: When you replicate data across regions, consider the local data residency laws because moving data across borders can have legal implications.

Getting started with IBM Cloud File Storage for VPC

If you are not already an IBM Cloud customer, it’s easy to sign up and get started. If you are already a customer, you can now provision VPC file shares using the IBM Cloud Console, API or CLI.

Get up to USD 1,000 in credits for new VPC file shares and VPC infrastructure by using the code VPC1000 at the time of provisioning or through the billing and usage section in the IBM Cloud Console.

Learn more

For more information about IBM Cloud File Storage for VPC, see the File Storage for VPC documentation.