Five Key Elements to Successful Legacy IT Migration

CIOs of large enterprise organizations are relentlessly challenged to keep costs down, security postures tight, and provision the latest and the greatest apps to user departments and customers.  It’s a tough enough job – even before the added headaches of dealing with legacy IT infrastructure.

Gartner predicts that by 2025, over 50% of government agencies will have modernized critical core legacy applications to improve resilience and agility.  Whichever of the many good reasons are driving your migration from legacy to modern infrastructure – security, costs, efficiencies, speed to innovation – such migrations must be done thoughtfully to avoid risks and disruption. This SDI blog highlights five key factors that drive successful legacy IT infrastructure migrations, drawing from our Team’s insights gained from over 25 years of leading large-scale and complex IT legacy migrations and modernization initiatives:

Experience Matters. Modernizing critical IT infrastructure is not for the faint of heart. The potential risks involved are varied – from losing key revenue generation for your organization, to losing critical data. Your migration project team should include server administrators, network engineers, desktop engineers, and application owners. “Experience speaks volumes,” states SDI’s  Mikell Morton, who recently led SDI’s team through a large municipal client’s server migration project that included 159 Linux and Windows servers. “This took complete team engagement to accomplish during a Pandemic.” Whether copying or moving critical data from one server to another or properly configuring your target server to replace the first, the project team must have had the experience to draw from to achieve a flawless migration.


In 2020, SDI took on the ambitious project of upgrading, replacing or simply decommissioning every server that was being maintained with an end-of-life operating system within an entire large Municipal IT environment. This included previous servers, that were owned by around 35 different Municipal support teams. Each support team and application had differing requirements as to what was needed to go forward, meaning individual meetings and strategies that had to be developed for each business case. The result was that the SDI Team successfully virtualized over 90% of our Municipal client’s previous environments. The year-long virtualization project was a great step at removing legacy individual server hardware dependency and providing the application support teams with a high availability (HA) on-premises virtual hosting environment that is one step closer to being able to move to the Cloud.


Understand the Nuances of Your Current Servers.  With so many moving parts and required precision, intimate knowledge of each legacy server in play is critical to set expectations for the migration pathway forward. Knowing the detailed history of the legacy environment is critical to guiding a low-risk migration. Your migration team must work together to explore and identify critical information of the native IT environment: why were the legacy machines brought in? What capacity Municipal was envisioned then and required today? What have the traffic and access patterns been over time? What departments and individual users’ critical data is required – and when? What is your end users’ planned growth over the next five years? The team should look through RAID logs, to go back to previous issues and anticipated risks. On the flip side, careful consideration should also be taken when determining the type of server, you will be moving toward. Your company’s IT strategy will provide direction on whether this is hardware-based or in the cloud. All this relevant information will dictate important details and direction within the migration plan.

Proven Processes Pay Off. A well-detailed and proven migration plan is essential for successful server migration. The plan starts at the onset of a migration approval and ends with a closed-out project. And should be followed for every single server! The plan should accommodate the different types and sizes of servers – some migrations require a rewrite of all apps, while some are simple. Your migration plan should factor in how to work with application vendors and other unique server situations. Make sure that your plan addresses common interdependencies with your user environment: Check APIs. Check network traffic. Check performance and latency. Have a rigorous testing process to confirm an error-free and complete environment. All these elements save time reconciling issues at a later date.

Communication is Key! With so much hanging in the balance, it is so critical to make sure that all stakeholders are on the same page and communicated correctly. Make sure that all stakeholders are identified and within a single communications channel (i.e.: group email or chat). For each stakeholder, get an emergency contact number. Early on, solicit each stakeholder asking for any important events that are transpiring at the time of the migration, as well as any high-visibility initiatives that might be impacted. Create a timeline to communicate with those who access server information, to let them know when the migration will be happening, how long it is expected to take, and when they can expect to resume operations. There should be no surprises during the active migration – and a thoughtful communications plan will ensure smooth sailing.

Document, Document, Document! It is especially important to document all aspects of server migrations, considering the many stakeholders are involved. Aside from the owner’s IT team, stakeholders may include multiple partners with equipment manufacturers, application vendors, and multiple client departments. Documentation should include network detail, applications with descriptions, owners of data, and the responsible departments.

As your organization looks to modernize its IT environment, it is critical to assemble a team that incorporates these five areas into its approach and project methodologies and selected partners. Modernizing IT infrastructure is imperative in today’s market to achieve necessary security and operability. Be prepared to make the needed commitment to ensure that your modernization initiatives are accomplished successfully.

SDI offers comprehensive IT modernization services that include strategic roadmaps, technical services, and ongoing IT infrastructure managed services. Each project is run by PMP-certified Project Managers, who leads a team of well-certified IT experts through our well-honed Migration methodology to deliver a cost-efficient and low-risk IT migration. Contact us for more information on how SDI can assist your organization with modernizing its IT legacy infrastructure.

About SDI’s Guest Bloggers

SDI’s Delivery Executive Mikell Morton is a leader in data center modernization, infrastructure management, and cloud operations with over 16 years of experience managing large data centers for private and public-sector organizations.

With proven experience in managing migrations to public and private cloud systems, Mr. Morton maintains a strong technical background, having served as the Data Center Manager and Sr. Manager – Cyber Infrastructure and Data Center Operations, Technical Support Manager, and Network Support Leader. He is certified in IT Infrastructure Library (ITIL) Foundations and AWS Leadership (Data Center).

SDI’s Senior Vice President of Managed Services Shanna Rahming is a former State Chief Information Officer and State Chief Strategy Officer with 3 decades of IT experience leading teams for modernization projects in both public and private sectors.  Ms. Rahming has a strong technical background in both infrastructure and applications and holds various IT certifications including IT Infrastructure Library (ITIL) Foundations.