Azure Firewall Manager policy overview

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Firewall Policy is the recommended method to configure your Azure Firewall. It's a global resource that can be used across multiple Azure Firewall instances in Secured Virtual Hubs and Hub Virtual Networks. Policies work across regions and subscriptions.

Azure Firewall Manager policy

Policy creation and association

A policy can be created and managed in multiple ways, including the Azure portal, REST API, templates, Azure PowerShell, CLI and Terraform.

You can also migrate existing Classic rules from Azure Firewall using the portal or Azure PowerShell to create policies. For more information, see How to migrate Azure Firewall configurations to Azure Firewall policy.

Policies can be associated with one or more virtual hubs or VNets. The firewall can be in any subscription associated with your account and in any region.

Classic rules and policies

Azure Firewall supports both Classic rules and policies, but policies is the recommended configuration. The following table compares policies and classic rules:

Subject Policy Classic rules
Contains NAT, Network, Application rules, custom DNS and DNS proxy settings, IP Groups, and Threat Intelligence settings (including allowlist), IDPS, TLS Inspection, Web Categories, URL Filtering NAT, Network, and Application rules, custom DNS and DNS proxy settings, IP Groups, and Threat Intelligence settings (including allowlist)
Protects Virtual hubs and Virtual Networks Virtual Networks only
Portal experience Central management using Firewall Manager Standalone firewall experience
Multiple firewall support Firewall Policy is a separate resource that can be used across firewalls Manually export and import rules, or using third-party management solutions
Pricing Billed based on firewall association. See Pricing. Free
Supported deployment mechanisms Portal, REST API, templates, Azure PowerShell, and CLI Portal, REST API, templates, PowerShell, and CLI.

Basic, Standard, and Premium policies

Azure Firewall supports Basic, Standard, and Premium policies. The following table summarizes the difference between these policies:

Policy type Feature support Firewall SKU support
Basic policy NAT rules, Network rules, Application rules
IP Groups
Threat Intelligence (alerts)		 Basic
Standard policy NAT rules, Network rules, Application rules
Custom DNS, DNS proxy
IP Groups
Web Categories
Threat Intelligence		 Standard or Premium
Premium policy All Standard feature support, plus:

TLS Inspection
Web Categories
URL Filtering
IDPS		 Premium

Hierarchical policies

New policies can be created from scratch or inherited from existing policies. Inheritance allows DevOps to create local firewall policies on top of organization mandated base policy.

Policies created with non-empty parent policies inherit all rule collections from the parent policy. The parent policy and the child policy must be in the same region. A firewall policy can be associated with firewalls across regions regardless where they're stored.

Network rule collections inherited from a parent policy are always prioritized over network rule collections defined as part of a new policy. The same logic also applies to application rule collections. However, network rule collections are always processed before application rule collections regardless of inheritance.

Threat Intelligence mode is also inherited from the parent policy. You can set your threat Intelligence mode to a different value to override this behavior, but you can't turn it off. It's only possible to override with a stricter value. For example, if your parent policy is set to Alert only, you can configure this local policy to Alert and deny.

Like Threat Intelligence mode, the Threat Intelligence allowlist is inherited from the parent policy. The child policy can add more IP addresses to the allowlist.

NAT rule collections aren't inherited because they're specific to a given firewall.

With inheritance, any changes to the parent policy are automatically applied down to associated firewall child policies.

Built-in high availability

High availability is built in, so there's nothing you need to configure. You can create an Azure Firewall Policy object in any region and link it globally to multiple Azure Firewall instances under the same Azure AD tenant. If the region where you create the Policy goes down and has a paired region, the ARM(Azure Resource Manager) object metadata automatically fails over to the secondary region. During the failover, or if the single-region with no pair remains in a failed state, you can't modify the Azure Firewall Policy object. However, the Azure Firewall instances linked to the Firewall Policy continue to operate. For more information, see Cross-region replication in Azure: Business continuity and disaster recovery.

Pricing

Policies are billed based on firewall associations. A policy with zero or one firewall association is free of charge. A policy with multiple firewall associations is billed at a fixed rate. For more information, see Azure Firewall Manager Pricing.

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