11.2. Azure Firewall
Azure Firewall is a managed, cloud-based network security service that protects Azure Virtual Network resources. It’s a fully stateful firewall as a service with built-in high availability and unrestricted cloud scalability. Azure Firewall provides a centralized means to control and log access and application traffic across all subscriptions and virtual networks, making it a vital component within a robust cloud network security architecture.
Understanding the significance and the functionalities of Azure Firewall requires an in-depth examination of its features, capabilities, operational governance, integration with other Azure services, and best practices for deployment.
Features and Capabilities
Azure Firewall is packed with features that address both north-south and east-west traffic in a virtual network, providing broad protection for your Azure resources. Here are some key features:
● Built-in High Availability: Azure Firewall is inherently highly available with no additional cost or configuration needed, ensuring that security is always maintained without manual intervention.
● Unrestricted Scalability: It can scale up as much as needed to accommodate changing workloads, with its cloud-native design ensuring that network performance is not compromised.
● Application Rule Collection: This allows you to define rules that filter outbound traffic based on fully qualified domain names (FQDN) in HTTP/S traffic.
● Network Rule Collection: These are traditional firewall rules that allow you to filter traffic based on protocol, source and destination IP address, port, and other parameters.
● Threat Intelligence: Integrated with Microsoft’s threat intelligence data, Azure Firewall can identify and block malicious traffic.
● Outbound SNAT Support: Azure Firewall provides source network address translation (SNAT) for outbound traffic, ensuring that virtual network traffic bound for the internet uses the firewall’s public IP.
● Inbound DNAT Support: Inbound destination network address translation (DNAT) allows outside clients to access services hosted inside of the Azure virtual network.
Operational Governance
Azure Firewall simplifies operational governance through:
● Centralized Policy Management: Utilizing Azure Firewall Manager, you can centrally manage firewall policies across multiple firewalls and Azure subscriptions.
● Logging and Analytics: Integration with Azure Monitor logs provides detailed logging, and when coupled with Azure Sentinel, it offers advanced analytics and threat detection capabilities.
● Integration with Azure Services: Azure Firewall can be seamlessly integrated with Azure services like Azure Security Center and Azure Logic Apps to automate responses to threats and improve security posture.
Integration with Other Azure Services
Azure Firewall can be a part of a larger suite of security tools within Azure:
● Azure Firewall Manager: This service provides central security policy management for multiple firewalls.
● Azure Security Center: Azure Firewall logs can be analyzed in Azure Security Center, providing a unified security management system.
● Azure Monitor: The service logs every event that passes through the firewall, which can be sent to Azure Monitor for visualization and analysis.
