Managing legacy technology

These principles describe how the government should manage legacy technology.

Defining legacy technology

Legacy technology can refer to your organisation’s IT infrastructure and systems, hardware, and related business processes.

Technology becomes legacy because of any or all of the following points. The technology now is:

  • considered an end-of-life product
  • out of support from the supplier
  • impossible to update
  • no longer cost-effective
  • now considered to be above the acceptable risk threshold

Issues that stop legacy technology migration

Most organisations will have an overarching IT strategy that complements the organisation’s business strategy. Your organisation’s IT strategies will consider the best approach to legacy migration which can include:

  • retain (do nothing)
  • retire (drop)
  • re-host (lift and shift)
  • repurchase (shop and drop)
  • re-platform (lift and shape)

Which strategy, or combination of strategies, your organisation uses will depend on its size and infrastructure complexity.

The main areas that cause technical blockers to legacy migration are the complexities associated with the:

  • age of the technology in use - older technology can become unstable and you may find it harder or expensive to find replacement parts if it needs repairing
  • dependent systems and services - you may find it difficult to discover how the infrastructure has evolved and how you can disaggregate additional dependencies away from old technology without causing a loss of service interruption to your users
  • data held by the organisation - you may find it difficult to know exactly what data you have or its schema, and how you can migrate it, especially if it is held using legacy or proprietary data stores
  • technical debt in legacy systems - this is often more expensive for you to resolve and takes longer to fix than in newer technologies if there is a lack of the right skills and tools in your team
  • size of the system or infrastructure and the time it takes you to migrate larger scale technology
  • security management of your migration
  • lack of proper documentation for your legacy technology - this causes lost time and money if you need to find out exactly what the technology is and how it runs before working out how to migrate it

Organisations are likely to have strategies for overcoming these technical issues. However, organisations may have trouble completing legacy technology migrations due to non-technical issues.

The main non-technical blockers for organisations are:

  • business and culture - an unwillingness to change current processes and ways of working may limit your ability to change legacy technology
  • commercial decisions and spending models - these may limit your choices for new technology and how you implement them
  • financial - limited IT budgets cannot always cover the costs of a migration
  • guidance and policy - policies may set guidance or targets that can limit what your IT team can change, for example, requiring hard copies rather than digital versions (an organisation’s policies can also encourage change by setting targets that can only be met with new technology)
  • resources and responsibilities - your IT team may not be big enough or have the skills required to migrate some legacy technology (you may have lost experienced team members or it may not be clear who owns the legacy technology)
  • use of multiple suppliers - coordinating them can cause delays in accessing data or equipment to allow your legacy migration
  • supplier contractual arrangements and exit strategies - these may delay how and when you migrate your legacy technology
  • aversion to risk - for example, your organisation may decide to keep their legacy on-premise solution and use it to build a complex hybrid cloud solution instead of migrating to a full cloud service
  • competing priorities - more urgent issues getting precedence over addressing legacy technology
  • legislative and ministerial requirements - the short delivery time frames of their requirements reduces the opportunities to change the legacy environments

When is it time to migrate your legacy technology?

The right time to migrate from your legacy technology will depend on your organisation. Reasons you decide to migrate may be:

  • the cost of maintaining old technology becomes greater than replacing it with new technology
  • reduced technology efficiency prevents necessary changes to services
  • supplier support for technology is no longer available
  • the contract for technology or its attached services is due to expire
  • the risk of maintaining technology becomes too great

Principles for managing legacy technology

  1. Aim to use continuous improvement planning to keep your technology up to date.
  2. Build a complete and accurate register of your data assets.
  3. Know the full extent of your systems and infrastructure.
  4. Build the skills and capabilities of your IT team.
  5. Have a flexible and responsive service model which can adapt to changing technology.
  6. Consider the organisation’s business needs, processes and culture.
  7. Use the Technology Code of Practice as a basis for your decisions.

1 Aim to use continuous improvement planning to keep your technology up to date

Use continuous improvement planning to implement an iterative or phased migration, and help prevent the accumulation of future legacy technology. The main benefits you will gain from using continuous improvement planning are the:

  • gradual retirement of technology which is generally cheaper and simpler than a full decommissioning legacy project
  • reduction of risks to your systems and infrastructure
  • focus on the reduction of legacy technical debt
  • reduction of risk to your migration

Doing iterative or phased migration can take extra planning, but by doing so you will have the processes in place to control and manage the amount of legacy technology that you have.

Continuous improvement may mean you need to consider:

  • allowing extra time and budget when adding new functionality or upgrading existing functionality
  • checking regularly for technology that needs updating or replacing
  • allowing time to do thorough documentation of any changes and additions made to the technology
  • using architects and senior technical staff to help check the documentation, systems and infrastructure
  • how to make sure the changes you make remain compatible and integrated with the rest of your systems and infrastructure
  • designing your system with components that you can swap and move easily

If you are using a supplier rather than an in-house team you will have to negotiate how continuous improvement will be added as a requirement into your contract.

Make sure the benefits of doing continuous improvement planning is understood by your senior managers.

2 Build a complete and accurate register of your data assets

The data and information in your system represents the true value of the system itself. It will be rare that you do not retain the information on the platform you are migrating or transforming.

Understanding your data and information will be an important factor in any legacy renewal programme.

Your organisation will need a data or information assets register for security and privacy reasons. This is a record of all the information you hold such as the technical documentation for all of your IT architecture and products. It will usually tell you:

  • the type of information you have
  • where the information is stored
  • how the information is secured
  • how the information should be handled

You should check your data asset register regularly and keep it up to date with any changes you make. These checks may also highlight any technology that has become legacy that you will need to migrate.

3 Know the full extent of your systems and infrastructure

Your organisation may have documentation showing the full extent of your systems and infrastructure, but in many cases you may not be confident that you have all of the information. There are many reasons why this may be the case including how your IT infrastructure has evolved over time or because you’ve lost corporate knowledge of the older systems. In these situations, you may find it helpful to employ Architect(s) and Technologist(s) to help map your infrastructure or update existing maps.

You can also schedule regular IT infrastructure reviews. How often you do this will vary depending on the size of the IT infrastructure. If you are using continuous improvement planning then these reviews will be part of your cycle to sense check the changes you’re making to your system.

IT infrastructure reviews usually comprise of several elements including infrastructure, performance management, service availability, security management and capacity management. These surveys should also consider:

  • your administration and business processes
  • whether your infrastructure still meets your organisation and user needs
  • whether your infrastructure integration is up to date
  • security and other risks that may now be affecting your system

Make sure that everything is clearly documented for ease of reference and use your findings from the infrastructure reviews to update the documents in your repository.

4 Build skills and capabilities of your IT team

The government’s policy is to encourage more training for all staff and provide opportunities for promotion and entrance into the civil service.

There is an emphasis on in-house specialists who can provide the expertise needed to:

  • build and maintain your organisation’s IT infrastructure and services
  • be ‘expert customers’ for your organisation if you’re using suppliers to provide your IT systems
  • bridge the gap between legacy and new technologies

There are resources on GOV.UK to help you train staff in current and new technologies.

These include:

To have the right skills, you need to create an environment where staff are encouraged to do training courses to expand their knowledge and expertise. You will also need to make sure your staff continue to receive training so they can maintain high standards with the latest technology.

5 Have a flexible and responsive service model which can adapt to changing technology

Your organisation is likely to be moving technology into the cloud and have a wider range of suppliers. As this move occurs you will need to consider how to make your service model more flexible.

When writing your IT service model consider whether your:

  • service model is meeting your users’ needs
  • IT team’s governance structure and processes help to align the IT and business strategies
  • operational processes are flexible to support both new technology or the depreciation of legacy technologies

You should also decide how you prioritise your technology migration and assess whether a change to the business would be a more flexible solution.

6 Consider your organisation’s business needs, processes and culture

When you have identified some legacy technology that needs migrating you should consider how the change will affect your organisation’s business processes and working culture. Your migration approval can be blocked if these additional circumstances are not taken into account.

To make sure there are as few blockers to your migration as possible you should consider your:

  • senior management priorities and concerns - address these directly in your planning
  • business unit’s understanding - make sure it understands the benefits of migrating and is willing to change your organisation’s business processes
  • user’s appetite for change - demonstrate and engage with your users why changing current working practices will be beneficial and that short term inconvenience will end in long term gain

In addition to your business case, consider:

  • involving senior management in your user research
  • involving users throughout your migration process so that changes do not come as a surprise
  • planning to allocate time and budget for user testing and training
  • having a strong communication plan to keep users informed
  • doing a risk evaluation for the proposed changes and include mitigations for each risk
  • how you manage supplier relationships and whether you have a good knowledge of their future plans

7 Use the Technology Code of Practice as a basis for your decisions

The Technology Code of Practice is a set of criteria to help government design, build and buy better technology. It’s used as a cross-government agreed standard in the spend control process.

Reviewing the Technology Code of Practice, and your other operating practices as described in this document will help you avoid accumulating legacy technology and prevent the issues associated with them. Retaining legacy systems beyond the best viable point of depreciation or replacement can cause the higher risks and costs mentioned in this document.

Published 21 February 2019