DocumentDB global cluster secondary region failure

Hello @awsPy,

If a secondary region goes down while using the global cluster with documentdb, will documentdb failover to other running regions automatically?

If a secondary region goes down while using the Amazon DocumentDB global cluster, DocumentDB will automatically failover to a running secondary cluster in another region. The failover process is designed to be fault-tolerant and minimize downtime.

Also, if we are performing only reads from the primary region and if it goes down, do we still need to implement the automation process for failover or will it redirect the reads to a secondary region?

Here's what happens if the primary region goes down while you're performing both reads and writes to an Amazon DocumentDB global cluster:

1. When the primary region goes down, DocumentDB will automatically fail over to a secondary region. This failover process typically takes less than 30 seconds.
2. During the failover, any writes that were in-flight to the primary region will be buffered and replayed to the new primary region once the failover is complete. This ensures that no writes are lost during the failover process.
3. Reads will be automatically redirected to the new primary region in the secondary AWS Region, ensuring high availability for both read and write operations.
4. After the failover is complete, your application can resume normal read and write operations to the new primary region. The global cluster will ensure that any data written to the secondary region during the failover is eventually replicated back to the primary region once it is restored.