When you hear the term “legacy” used in the media, it’s usually used to compliment someone who is a trailblazer or pioneer.
However, in the IT world it is nearly always used to describe a problem system, typified by high costs to substitute, upgrade or integrate with, and seemingly impossible to replace (mainframe computing anyone?). In other words, this system may have significant value but it is holding the business back.
To avoid this pitfall, rather than making tactical decision-making creating an investment sinkhole, what is needed is an IT strategy with a detailed technology roadmap. By lifting the company view from immediate (tactical) to longer term (strategic) is the game changer, however, realistically it is a combination of the tactical and strategic solutions.
Let’s take a look at the various ways to deal with legacy IT systems:
Putting a workaround in place is often tempting when costs start to go through the roof. This sometimes starts out as a short-term exercise only to end up as a permanent solution. Manage this approach closely.
Pro: Short term it achieves the business goals
Extends the investment of the system
Con: May need specialised skills (and they are usually expensive)
The pain drags on, especially for the staff who use the systems
Putting off the inevitable may end with a large cost later.
Complement with Cloud
If possible offload as much functionality to a cloud service. For example, using O365 for email services, however, delay the move to OneDrive and continue to use your local file server. Moving file stores can be complicated, with user and system touch points that need to be considered.
Pro: Reduces the dependency on the system over time
Phased approach has less immediate impact on the business operations
Con: Complicates the environment
Extends the time frame to exit the legacy system
Ringfence and Air-Gap
Place the system in its own self-contained environment such as using virtualization technologies, moving to a dedicated network, or use a platform such as Citrix XenApp. A common example of this approach is when vendor support has expired and no further security patches will be released. Ringfencing will contain potential virus outbreaks that may be targeting older systems, mitigating the impact.
Pro: Buys more time to get a strategic solution in place
Extends the investment of the system
Con: Adds complexity to the environment
Only a short term solution
Build Replacement in Parallel
If you have the resources, then this approach is one to consider. Building in parallel mitigates risk to the business and allows for proper end to end testing before being introduced.
Pro: Less disruption to business, where the old system continues to service the business until the new is built, tested and readied
A structured and clean approach
Does not add complexities to the environment
Shorter times to implement, teams can focus on the project of delivering the new system
Con: Costly to operate 2 systems at the same time
Infrastructure capacity needs to be considered carefully
Data migration may be complicated and lengthy adding to the cost and impacting schedule
Step change has more impact on operational staff
These days this is often labelled the agile approach and does align nicely with the Agile project management methodology. That said, the phased approach can be implemented via a number of project methodologies.
Pro: Spread the costs over time
The business realises the benefits from each phase and does not need to wait until the end of the entire project
Gradual introduction gives staff time to adjust to the new processes
Con: Longer implementation times
Project complexity increases
Whichever approach you go for, the main aim is to avoid creating technical debt, in other words – the additional future costs created from a shortcut or poor decision made today. Starboard IT have extensive experience in managing legacy systems and have implemented all approaches listed in this article. We would love to talk
Starboard IT have extensive experience in managing legacy systems and have implemented all approaches listed in this article. We would love to talk through your particular legacy systems and discuss the best way forward.