GitLab’s journey from Azure to GCP

This post details GitLab's migration from Azure to Google Cloud Platform (GCP). The migration was guided by the core values of efficiency, iteration, and transparency. The initial plan to stop the whole site and copy data was deemed too time-consuming. The team leveraged the developing GitLab Geo feature for replication to a secondary instance in GCP. The plan evolved to use Omnibus for provisioning and migrating file artifacts to Google Cloud Storage (GCS). The failover procedure was meticulously planned and iterated upon using issue templates and merge requests, resulting in over 140 changes to the checklist. The migration resulted in significant improvements in availability (from 99.61% to 99.93%) and reduced error rates and latency. Key learnings include the value of transparency, iterative development, and understanding DevOps lifecycle management from companies like Google.