The provided script is used to configure IPtables on a Linux-based server to allow incoming traffic on specific ports related to Couchbase DB Server and sync_gateway. The script includes rules to accept incoming traffic on various ports, such as 4369, 8091, 8092, 11209, 11210, 11211, 11214, 11215, 18091, 18092, and 21100-21199. To confirm the configuration is correct, the script recommends running `iptables --list` as root and verifying that the REJECT rule for the INPUT chain is at the end. It's essential to note that this script is for local server security purposes only and does not replace a network firewall or AWS security groups/network ACLs. The user should perform their own due diligence when it comes to system security.