Data migration from legacy systems - how to do it effectively

Jerzy Zawadzki - Chief Technology Officer
7 minutes read

One significant challenge in updating your legacy applications is the complexity of legacy data migration.

It involves transferring data from outdated systems to more advanced and efficient platforms, but how to tackle it best? Is there any golden rule to follow, or rather a dozen factors to consider?

Today, we’ll guide you through the legacy data migration process that can be implemented in your company, so let's get down to business.

Legacy data migration step-by-step

Data migration from legacy systems is not a one-step process. On the contrary, it includes several steps to make the entire project safe and efficient, and no data will be missed.

Here's where to begin.

#1 Plan the migration

Planning the migration lays a solid foundation for a successful legacy data migration process and ensures that the journey ahead is well-charted and achievable. To start, you need to:

Set clear objectives

Before diving into the technical aspects, you must understand what you're trying to achieve. This first move is the heart of a successful migration.Therefore, ask yourself:

  • What are the end goals?
  • Are we aiming for better performance, more storage capacity, enhanced security, or all of the above?

Setting clear, measurable objectives at the outset guides every decision and action in the migration process, helps in assessing progress, and, importantly, in making wise decisions when unexpected problems arise.

For instance, if your primary goal is to improve data security, your migration plan will significantly focus on selecting tools and processes that strengthen data protection.

Identify stakeholders and form a skilled migration team

As migrating legacy data isn't a one-person show, it requires a team with diverse skills and insights. So, identify key stakeholders across various departments, like: IT, operations, finance ,and even end-users.

Their input is crucial as they understand the nuances of how data is used across the organization.

Once stakeholders are identified, it's good to form your migration team.

This team is a blend of internal talents – those who know your current systems inside out – and possibly external experts specializing in data migration. They should be equipped to handle technical threats, coordinate efforts across departments, and ensure that the migration aligns with your objectives.

Regularly communicate with stakeholders and team members, address concerns promptly, and keep everyone informed about the progress for a smooth migration process.

Conduct a thorough assessment of the existing system

Now, let's turn our attention to the legacy system, as its thorough assessment is a must. This step is like mapping the terrain before setting out on a journey. Here, you need to understand the scope of the data – its volume, complexity, and sensitivity.

This assessment should answer many questions, like:

  • What data formats are we dealing with?
  • Are there any data quality issues?
  • What are the dependencies and integrations that need to be considered?

The insights gained from this assessment are invaluable in planning an efficient and effective migration. Knowing what's not working well in the old system can guide you in optimizing the new one. Maybe there are performance bottlenecks or scalability issues you want to avoid in the future setup.

Select the right migration tools and technology

Selecting the right migration tools and technology depends on various factors – the size and complexity of your data, your budget, and your IT infrastructure.

Ask yourself if you are looking for an on-premises solution or if you want to move to the cloud. Also, do you need tools that can handle large volumes of data efficiently, or do you just look for something that offers more in terms of data cleansing and quality management? Here, there isn't one best solution that fits everywhere, so you need to do your research and find the one that is good for you.

This selection process often involves:

  • evaluating different vendors,
  • considering recommendations from your IT team and consultants,
  • and perhaps even running pilot tests to check compatibility and performance.

The tools and technology should align with your migration goals, fit within your budget, and integrate seamlessly with your new system.

#2 Prepare for the process

The next stage is about preparation. After planning and before migrating, you need to arrange a bunch of things. For example:

Do backups

Backups are your safety net. Before any data is moved, it's critical to create comprehensive backups of all data in the legacy system. This step is non-negotiable as it protects against data loss that can occur due to unforeseen issues during the migration.

Think of these backups as your insurance policy – you hope you never need to use them, but you'll be glad you have them if something goes wrong.

Thus, it's not just about creating them. This step aims to ensure they are reliable and can be restored effectively. So, after you make backups, test them to confirm that data can be recovered without corruption.

Best practices about backups:

  • Strategize their storage and accessibility.
  • They should be secured and separated from your primary data storage, yet in an easily accessible location.
  • As your legacy system continues to operate, new data generated should also be backed up.
  • Thanks to this, no recent data is lost or harmed during the transition.

Prepare the environment

Next up is preparing the new environment, which is akin to setting up your new headquarters before moving in. This entails configuring the new system, setting up databases, and confirming that the infrastructure is ready to receive the migrated data.

Preparing the new environment often requires collaboration between different IT teams to make the new place optimized for performance, scalability, and integration with other systems.

If you're moving to the cloud, for example, this might involve configuring cloud services, setting up virtual machines, or establishing data storage solutions.

Above that, make sure your team is ready for the transition. Train the staff who will be working with the new system and prepare documentation that details how the new system operates.

Ensure compliance and security considerations

Migrating data, especially sensitive or regulated ones, needs adherence to legal and regulatory standards. This could include GDPR, HIPAA, or other industry-specific regulations. So, in this step, you inspect if the data is handled, stored, and transferred in compliance with these regulations.

Pay attention to:

  • setting up security protocols,
  • data encryption,
  • access controls,
  • and audit trails.

Moreover, check if the new system is hardened against cyber threats and that data privacy is maintained throughout the migration process.

The new system should not only be compliant at the time of migration but also adaptable to future regulatory changes. This forward-thinking approach will make the system secure and compliant, even as regulations evolve.

#3 Execution of migration

Now, the execution phase. It’s the time when all the plans, strategies, and preparations are put into action. It requires precision, agility, and continuous oversight. At this point:

Choose a migration strategy

Each legacy migrating method has its advantages and considerations, so carefully execute all the pros and cons and choose the one that is best for your needs.

In data migration, the primary methods are Big Bang, Phased, Parallel, and Trickle migrations.

Big bang database migration means migrating all the data in one phase. The entire database is moving from one system to another, so here, you need a high level of preparation. They are quick but risky.

Phased migrations mean data is transferred in several segments. At each stage, you can eliminate errors, which can make it easier to train employees on the new system. They reduce risk but take longer.

The Parallel method offers the lowest level of risk, as the new system runs alongside the older system until all bugs are fixed. They offer a safety net but can be resource-intensive.

Trickle migration divides the process into sub-processes, does not cause system downtime, and is less vulnerable to errors. Such migrations are continuous but can be complex.

Choosing a data migration strategy should be based on your organization's size, risk tolerance, and downtime feasibility. It will shape the entire migration journey and should balance technical feasibility, business continuity, and resource availability. Thus, align it with your objectives, resources, and timeline.

Test data migration

Before the full-scale migration, you should test your migration strategy. This test entails moving a portion of the data to the new system to validate every aspect of the migration process - from the functionality of the tools to the integrity of the data.

This move helps to:

  • identify any discrepancies in data,
  • ensure that the data is correctly mapped,
  • check if it's formatted for the new system.

The testing phase is crucial for catching and addressing issues, thereby it reduces risks during the actual migration.

Perform migration and eliminate errors

Now is the time to carry out the migration and react accordingly. Even with thorough planning and testing, you may face some challenges. They could range from data format discrepancies, and unexpected system incompatibilities, to performance bottlenecks.

Thus, the migration team must be prepared to identify and resolve issues as they arise quickly. This demands a deep understanding of both the legacy and new systems, as well as the tools being used for migration.

Effective communication among team members is also crucial if you want to swiftly eliminate these challenges and ensure that every obstacle is turned into a stepping stone toward successful migration.

#4 Post-migration activities

Post-migration activities are the final steps in the legacy data migration process. Thanks to them, the transition to the new system is not only successful in the short term but also sustainable and advantageous in the long term. Here you must:

Monitor and assure quality

Monitoring and quality assurance will keep an eye on the migrated data and verify that they move as planned. They help detect any issues so early, whether it's data corruption, loss, or performance problems.

Monitoring can also maintain the integrity and accuracy of the data and take care that the migration process adheres to the pre-set performance benchmarks. Bet on regular checks, as they can verify the data and maintain quality and structure.

Retire and get rid of the legacy system

Once you’ve confirmed that the legacy system is no longer needed, the next step is to dispose of it responsibly. Turning off the old servers and saying goodbye isn't enough. All sensitive data must be securely wiped, and the disposal of hardware must comply with environmental and data protection regulations.

Decommissioning the legacy system is a big milestone – it symbolizes the end of an era and the full transition to a new, more advanced system. That's why it's better to eliminate it (of course, after all necessary data has been successfully migrated and is fully functional in the new system).

Get a partner in legacy database migration

Woah, that’s a lot, isn’t it?

For many companies, it may turn out to be too much because you have to remember so many steps and watch out for mistakes. Especially small businesses or those without extensive budgets, resources, in-house experts, or experience in data management can feel legacy database migration is too hard.

This is where finding the right partner like Polcode becomes crucial.

If you're feeling overwhelmed by the intricacies of data migration, or if you don’t have the resources to handle such a project smoothly, just reach out to Polcode.

By working with us, you’re gaining a partner who can help you through the entire process, from planning and execution to post-migration activities. Polcode’s team can help you address technical issues, ensure compliance with data standards, and significantly reduce the risk of data loss or corruption.

So, save you a considerable amount of stress and choose a smooth, efficient legacy data migration with us.

Don’t be afraid of migrating legacy data to modern database

Data migration from legacy systems is an important topic if you are still dealing with old software. Such migration can help you eliminate future problems and allow you to operate more securely. But the case is you don’t need just to migrate data. You need to make sure you do it smartly.

If you don’t feel confident about managing legacy system migration services on your own, contact Polcode. Our team of experts will identify your needs and meet your goals as best it can.

On-demand webinar: Moving Forward From Legacy Systems

We’ll walk you through how to think about an upgrade, refactor, or migration project to your codebase. By the end of this webinar, you’ll have a step-by-step plan to move away from the legacy system.

moving forward from legacy systems - webinar

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