Set up the redshift integration.
Confirm Redshift clusters are not publicly available.
Publicly available Redshift clusters have a public IP address, which gives any machine the opportunity to attempt to connect to your clusters. Malicious activity, such as SQL injections or distributed denial-of-service (DDoS) attacks, can occur if a connection is established.
Follow the [Managing clusters in a VPC] docs to learn how to modify public accessibility for your clusters.