Nailed the first half, talked about traffic filtering and blocking unauthorized access, felt good.
Start by defining a firewall's core purpose—enforcing network security policies by filtering traffic—then walk through a structured configuration process, emphasizing trade-offs between security and usability. Tailor your answer to Google's scale by discussing distributed firewalls and automation.
Pro tip: Mention that at Google's scale, manual firewall configuration is infeasible; instead, infrastructure-as-code and centralized policy management are used to ensure consistency and auditability.
Explain that a firewall acts as a barrier between trusted and untrusted networks, controlling incoming and outgoing traffic based on predetermined security rules.
Gather requirements such as which services need to be exposed, which IP ranges should be allowed, and compliance or logging needs.
Create a default-deny policy, then add specific allow rules for necessary traffic, following the principle of least privilege.
Use infrastructure-as-code tools (e.g., Terraform, Ansible) to deploy and manage firewall rules consistently across environments.
Enable logging and monitoring to detect anomalies, and regularly review and update rules based on changing needs and threat landscape.
AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.