market-db is available in the private subnets of the VPC market, behind db-sg, which lets in the app's group app-sg. The app server app runs in public-a with an instance profile for Session Manager. On it, /opt/market/catalogue.sql creates the catalogue and /opt/market/db-password holds the master password (user market, database market).

1. Keep market-db's endpoint in EP, and put it in the parameter /market/db/endpoint.
2. Start a session on app. Install the PostgreSQL client, read the endpoint from the parameter, and load the catalogue into the database. Find the most expensive monster.
3. exit the session. Make market-db Multi-AZ now, not in the maintenance window, and wait until the change is done.
4. Test a failover. Check that the endpoint has not changed and that the primary is now in the other zone, and read the event that says so.
5. Finance's reports must not slow the shop down. Give them a read replica market-db-reports.
6. When it is available, check from app that the replica has the whole catalogue, and that it refuses a change. The app's role cannot describe RDS instances, so paste the replica's endpoint into the session.