The first step that a tester should perform to determine if the new containers are configured correctly against a DDoS attack is to scan the containers for open ports. Open ports are entry points for network communication and can expose services or applications that may be vulnerable to DDoS attacks. Scanning the containers for open ports can help the tester identify which services or applications are running on the containers, and which ones may need to be secured or disabled to prevent DDoS attacks. Scanning the containers for open ports can also help the tester discover any unauthorized or malicious services or applications that may have been installed on the containers by previous attackers or compromised containers. Scanning the containers for open ports can be done by using tools such as Nmap, which can perform network scanning and enumeration by sending packets to hosts and analyzing their responses1. The other options are not the first steps that a tester should perform to determine if the new containers are configured correctly against a DDoS attack. Testing the strength of the encryption settings is not relevant to DDoS attacks, as encryption does not prevent or mitigate DDoS attacks, but rather protects data confidentiality and integrity. Determining if security tokens are easily available is not relevant to DDoS attacks, as security tokens are used for authentication and authorization, not for preventing or mitigating DDoS attacks. Performing a vulnerability check against the hypervisor is not relevant to DDoS attacks, as the hypervisor is not directly exposed to network traffic, but rather manages the virtual machines or containers that run on it.