Google Professional Cloud Database Engineer Question 210
Select 3Google Cloud PlatformYour organization is planning to migrate its primary relational database from an on-premises data center to Google Cloud Spanner. The database holds critical data and must remain accessible during the migration process. The team has decided to follow a zero-downtime strategy. Which of the following actions are necessary to successfully execute this migration strategy?
- A
Set up a bidirectional replication process between the on-premises database and Cloud Spanner.
- B
Perform a full database backup and restore it to Cloud Spanner before starting the migration.
- C
Test the application with Cloud Spanner in a staging environment before the final cutover.
- D
Configure the application to write simultaneously to both the on-premises database and Cloud Spanner during the migration.
- E
Disable user access to the on-premises database during the migration to ensure data consistency.
Show answer and explanation
Correct answers: A, C, D
Explanation
A zero-downtime migration strategy requires ensuring continuous data availability and consistency throughout the migration process. Setting up bidirectional replication ensures data synchronization between the source and target databases. Testing the application in a staging environment minimizes risks during cutover, and enabling simultaneous writes to both databases ensures a seamless transition without disrupting user access. Disabling access or relying solely on backup and restore would introduce downtime or risks to data consistency.
- A. Correct.
Setting up bidirectional replication ensures that changes made to either the on-premises database or Cloud Spanner are synchronized, which is critical for zero-downtime migration.
- B. Incorrect.
Performing a full database backup and restore alone would result in downtime and is not aligned with a zero-downtime migration strategy.
- C. Correct.
Testing the application in a staging environment ensures that any compatibility or performance issues with Cloud Spanner are identified and resolved before the final cutover, which is essential for a seamless migration.
- D. Correct.
Configuring the application to write to both the on-premises database and Cloud Spanner ensures data consistency and smooth transition during the migration process.
- E. Incorrect.
Disabling user access to the on-premises database contradicts the zero-downtime requirement since users would experience an outage.