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3 Techniques to Minimize Downtime During a Data Migration Process

Source: Kerem Gülen/Midjourney

Don’t let data migration downtime get you down

Transferring data during the cloud migration process can be a formidable challenge that requires proven strategies to minimize downtime. Where your data is stored during the migration plays a crucial role in determining the performance of your application. Delay and bandwidth problems may arise if you migrate your services without concurrently migrating the data. This can lead to a situation where your data is accessed over a significant distance between your on-premises and cloud data centers.

Achieving and maintaining data integrity, synchronization, and self-consistency throughout the transfer is a daunting task that requires meticulous coordination. The migration team might encounter big technical challenges when trying to achieve strict correlation. Forcing application downtime may not be possible for company operations.

For optimal performance of your applications, migrating both the data and the associated services simultaneously is crucial. However, determining the timing and method of data migration concerning the services can be a challenging decision. To ensure a successful cloud migration, companies often enlist the expertise of a migration architect, who can significantly impact the outcome.

Selecting the relevant data for migration

Collaboration with system, database, and application development experts as well as the business leaders can aid in identifying the potential data sources that may not be required to be migrated to the cloud. Determining which data sets should be transferred is a critical decision that requires thorough analysis. It is essential to ask pertinent questions to determine the data sources for migration, such as: 

  • Is it necessary to migrate the entire database or only a section of it?
  • Are there any redundant data archives that can be discarded?
  • Does any of the data require processing to reduce data volumes or enhance data quality before the migration?

Careful examination of present data resources and the rationale behind transferring them to the cloud can aid in reducing the quantity of data requiring migration. Taking this type of approach can significantly reduce the duration of the migration process and potentially avoid any hiccups or hold-ups that often surface during the migration of vast data sets.

How to minimize downtime during a data migration process

Whether you have an in-house cloud architect or not, there are three primary types of data migrations to move application data to the cloud:

  • System blackout migration
  • Dynamic replica migration
  • Synchronized migration

Each of these strategies necessitates a distinct amount of effort, impacts the availability of your application differently, and poses varying levels of risk to your business, regardless of whether you’re moving a SQL database, a NoSQL database, or raw data files. While you might find some similarities between the different migration methods, the variances lie in the specifics.

First technique: System blackout migration

In a system blackout migration, you bring down your on-premise application, transfer the data from the on-premise database to the cloud-based database, and then bring your application back online in the cloud. Although this method is simple, easy, and secure, it requires shutting down your application, which can result in significant downtime if you have a large dataset. This downtime can also adversely affect your customers and business operations.

With most applications, the amount of downtime during a System Blackout Migration is generally unacceptable. However, if your dataset is manageable, and your business can tolerate some downtime, this approach is the easiest, least expensive, and least risky way to move your data to the cloud.

Second technique: Dynamic migration

The dynamic migration approach aims to minimize downtime while keeping the data migration process relatively straightforward. First users begin with the master version of their database running in their on-prem data center. Next, users need to set up a read replica copy of their database in their cloud with one-way data synchronization from their on-prem master to their cloud replica. This type of master-replica model is standard with most database systems.

During the migration process, all data updates and changes are still made to the on-premise master, and the master replicates these changes to the cloud-based replica. Even after migrating and deploying your application in the cloud, you will continue to make data writes to the on-premise master. At a predetermined time, you will “switch over” and swap the master/read replica roles. The replica in the cloud takes over as the primary, while the on-prem master becomes a replica for reading. All write access is then moved from your on-premise database to your cloud database.

While a short downtime is necessary during the switchover, it is considerably less than the downtime required for the offline copy method. However, downtime is still downtime, and it’s crucial to evaluate how much downtime your business can handle.

Third technique: Synchronized migration

Out of the three data migration strategies, synchronized migration is the most intricate and poses the highest risk. Nevertheless, if executed correctly, this approach can facilitate seamless data migration without any application downtime.

To do this, users need to create a replica of their on-premise database master in the cloud and establish bi-directional synchronization between the two masters. This allows for the synchronization of all data from the on-premise database to the cloud and vice versa, resulting in a multi-master database configuration.

Once both databases are configured, you can access and edit data from either the on-premise or cloud database, and both will remain synchronized. This flexibility enables you to move your applications and services independently, based on your schedule, without having to worry about data migration challenges.

In order to minimize downtime during the data migration process, you can run instances of your application both on-prem and in your cloud and redirect your application’s traffic to your cloud minimizing any downtime. In case of any issues, you could switch back to the on-premise version of your database while you troubleshoot the problem.

Once the migration is complete, you can switch off your on-premise master and use your cloud master as your database. However, it is important to note that this method comes with its own set of complexities. A multi-master database setup can be challenging and may lead to skewed data and other unfavorable outcomes if not managed properly.

For instance, simultaneous data updates in both masters can cause issues, and reading data from one master before the other master has synchronized the data can also lead to problems. Therefore, this approach is only feasible if your application’s data access patterns and management strategies can support it. You will also need application-specific synchronization and sync resolution routines to tackle any synchronization-related issues that may arise.

If your application, data, and business can handle this migration method, this is the most streamlined and straightforward of the three strategies.

Don’t get caught off guard

Data migration is a complex process that requires careful planning, execution, and management. Despite best efforts, unforeseen issues may arise, such as inaccurate estimations of the required time to complete the migration or the amount of downtime incurred. The consequences of these unexpected problems can be significant, leading to data loss, application downtime, and potential business disruption.

Therefore, having strategies in place to minimize downtime during a data migration process is critical to ensuring that businesses can maintain operational continuity, avoid financial losses, and safeguard their reputation. Organizations must leverage sophisticated strategies and tools to mitigate risks and address issues as they arise, ultimately ensuring a seamless and successful data migration process.

How GRAX can help minimize downtime during application data migrations

GRAX provides organizations with a flexible and secure Salesforce data backup and restore service, which enables users to own and deploy data protection to their preferred on-premises or cloud infrastructure for Salesforce backup. With GRAX’s Bring Your Own Infrastructure model, businesses can have complete ownership and control over their historical Salesforce data and achieve enhanced security posture for Salesforce data protection. They can also benefit from continuous hourly backups, which run without any manual intervention, ensuring high-frequency backups for all their data objects.

This approach empowers organizations to easily replicate their Salesforce data easily into their preferred storage system they own and control 100%. Furthermore, GRAX provides users with the highest fidelity backup RPO (Recovery Point Objective) for all Salesforce data and files. GRAX Auto Backup captures the Salesforce application data, automatically backing up all Salesforce objects, their data, and files without any manual intervention, ensuring business continuity during data migration projects.

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