Microsoft plans to migrate most of its internal applications to its Azure cloud as it prepares to close two data centres and replace thousands of servers.
In a blog post, the company detailed plans to modernise its infrastructure, moving applications such as HR, finance and internal training systems to the cloud as part of a hybrid strategy. Certain systems will remain on-premise.
The work will be carried out by Microsoft IT's Service Deployment and Operations (SDO) team, which manages more than 40,000 operating systems hosting internal applications.
"Microsoft IT has adopted a cloud-first approach to applications and workloads," the company said.
"We have been using Microsoft Azure as the default infrastructure for new applications and workloads to further this cloud strategy."
The company said the migration is a result of two challenges it faces. One is that two of its data centres will be closed in the next 24 months as leased locations are decommissioned. It also faces the prospect of replacing servers that are reaching 'end of life' at the other five data centres it operates globally, which would cost up to $200 million in the next five years.
Microsoft hopes to remedy this by moving systems to Azure with "significant migration velocity".
Commodity workloads will be run on software as a service (Saas) tools, while new development and modern applications will rely on a platform as a service (Paas) system.
Existing applications will be moved to infrastructure as a service (Iaas) or remain in a private cloud. The work is expected to be complete by the end of 2018.
Microsoft's Azure platform experienced problems in the past two weeks, with a number of service interruptions and outages globally.