DNS attacks, often humorously blamed for outages, are critical for assessing and improving the resilience of online services, as demonstrated by Gremlin's DNS attack tool. The Domain Name System (DNS) is essential for translating human-friendly domain names into IP addresses, and disruptions can lead to widespread service failures. Gremlin's DNS attack simulates DNS outages by blocking DNS traffic, allowing organizations to test their systems' ability to withstand and recover from such incidents. The tool offers customizable parameters for controlling the attack's magnitude and blast radius, including targeting specific IP addresses, network protocols, and service providers. Running these attacks helps verify the effectiveness of mitigation strategies like fallback DNS servers and multiple DNS providers, ensuring systems remain operational during real-world DNS failures. By experimenting with DNS attacks, teams can identify vulnerabilities, track improvements, and demonstrate the value of resilience strategies to stakeholders.