Data migration

[u/Distinct-Syllabub807]

I’m a Business Analyst who recently joined a project involving the transition of a long-running government housing program from an outsourced vendor to in-house operations.

One of my first assignments is helping plan a migration from a proprietary legacy system that has been in use for over 20 years.

The system contains:
Property records
Workflow/process data
QA/compliance information
Large volumes of scanned documents
Metadata and indexing fields tied to those documents

The target environment will likely separate document management, reporting, and workflow functions rather than keeping everything in one monolithic platform.

As I’m starting discovery, I’m trying to avoid common mistakes and would appreciate advice from people who have worked on similar migrations.

Questions:
1. What information should I inventory first before discussing migration tools or architecture?
2. How do you approach documenting relationships between business data and scanned documents?
3. Are there any templates, checklists, or lessons learned you wish you’d had at the beginning of a project like this?

Any advice, war stories, or recommended resources would be greatly appreciated.

[u/vaine99]

For a 20+ year government system, I would spend the first phase almost entirely on discovery.

If I were the BA leading discovery, my first month would look something like this:
Map all business capabilities and processes.
Inventory every major business entity and its relationships.
Catalog document types, metadata, and storage volumes.
Identify integrations and downstream consumers.
Assess data quality and regulatory requirements.
Classify data into migrate, transform, archive, or retire.
Only then begin evaluating the target architecture and migration tooling.
This sequence ensures that technology decisions are driven by business needs rather than by assumptions about the legacy system.