Havering Council: Migrating 20 TB of Data from Legacy Systems to Microsoft 365

Overview

Moving a council's information into the cloud

The London Borough of Havering is a local authority in north-east London, delivering services including social care, housing, education and planning to its residents.

Years of council information had accumulated on legacy systems. Those systems were becoming harder and more costly to maintain, and they did not support the flexible, remote working that council staff increasingly needed.

Havering chose Microsoft 365 as its platform for documents and collaboration. Konsolute planned and delivered the migration of 20 TB of data from the legacy systems into Microsoft 365, organising it in a structure that supports how council teams work today.

The challenge

Scale, sensitivity and service continuity

Migrating 20 TB of data is a substantial undertaking. At that scale, careful planning is needed to manage throughput, validate results and schedule the work so it does not compete with day-to-day operations.

Council data is also sensitive. Information about residents, care, housing and finances had to remain protected throughout, with access in the new environment matching the council's responsibilities.

Most importantly, council services could not stop. Staff needed continued access to the information they relied on throughout the migration.

Havering needed to:

Our approach

Plan the scale, then migrate in controlled phases

We treated the migration as a programme, planning around data volumes, sensitivity and service schedules rather than moving everything at once.

Assessment. Konsolute assessed the content held on Havering's legacy systems, including volumes, structures, permissions and owners. This shaped the target structure and the sequence of migration.

Target structure. Content was mapped to a Microsoft 365 structure organised around council services and teams, so information would land somewhere that made sense to the people using it.

Phased migration. The 20 TB was migrated in planned phases, scheduled to minimise impact on council operations. Each phase was validated before the next began, confirming content and permissions had arrived as expected.

Access and security. Permissions were mapped to the new environment to reflect the council's roles and responsibilities, so sensitive information remained protected in its new location.

Staff support. Communications and support helped teams understand when their content would move and how to work with it in Microsoft 365.

Result

20 TB migrated, services uninterrupted

Havering's 20 TB of data now lives in Microsoft 365, organised around council services and protected by appropriate access controls.

The phased approach kept council services running throughout. Staff continued to access the information they needed while it moved, and each phase was validated before the next began.

With its information in Microsoft 365, the council has reduced its reliance on legacy systems and gained a platform that supports secure collaboration and flexible working.