3 strategies for zero downtime database migration

Cloud migration involves complex processes, particularly when moving data, which can significantly impact application performance if not handled simultaneously with service migration. Key challenges include potential latency issues from accessing data across distant locations, risks of data inconsistency, and application downtime during data transfer. Successful migration requires expert planning, encompassing database inventory, risk analysis, data cleansing, schema mapping, and backup strategies. Three primary data migration strategies are highlighted: offline copy migration, which is straightforward but involves considerable downtime; master/read replica switch migration, which minimizes downtime by synchronizing data to a cloud-based read replica before switching roles; and master/master migration, which is complex but allows for zero downtime by maintaining synchronized bi-directional data between on-premise and cloud databases. The role of a migration architect is emphasized for ensuring a smooth transition. Additionally, ongoing monitoring, using platforms like New Relic, is crucial to maintain application availability and data integrity throughout the migration process, especially for large datasets, where tools like AWS Snowball can assist but require complementary strategies for effective data transfer.