What should be done to ensure that the web tier does not come online before the database is completely configured?
Use Amazon Aurora as a drop-in replacement for RDS MySQL. Use snapshots to populate the table with the correct data.
Modify the launch configuration of the Auto Scaling group to pause user data execution for 600 seconds, allowing the table to be populated.
Use AWS Step Functions to monitor and maintain the state of data population. Mark the database in service before continuing with the deployment.
Use an EC2 Auto Scaling lifecycle hook to pause the configuration of the web tier until the table is populated.
Explanations:
Amazon Aurora could improve performance and management but does not inherently solve the issue of ensuring that the web tier does not come online until the database is ready. Snapshots would not guarantee the database population timing and synchronization with the web tier.
Pausing user data execution for a fixed period (600 seconds) does not guarantee that the database will be populated by the time the web tier is ready. It could lead to unnecessary delays or errors if the population takes longer than expected.
AWS Step Functions could manage the process flow, but implementing them adds complexity and does not directly control the scaling and deployment of the web tier based on the database population. The web tier could still attempt to come online before the database is ready.
Using an EC2 Auto Scaling lifecycle hook allows the process to pause instance launch until the SQL query execution is complete. This ensures that the web tier will not be considered in service until the database is fully configured, aligning the deployment process with the database readiness.
I reckon the answer is:
Use an EC2 Auto Scaling lifecycle hook to pause the configuration of the web tier until the table is populated.