Set up a geo-filtering WAF policy for your Front Door
This tutorial shows how to use Azure PowerShell to create a sample geo-filtering policy and associate the policy with your existing Front Door frontend host. This sample geo-filtering policy will block requests from all other countries/regions except United States.
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Before you begin to set up a geo-filter policy, set up your PowerShell environment and create a Front Door profile.
Set up your PowerShell environment
Azure PowerShell provides a set of cmdlets that use the Azure Resource Manager model for managing your Azure resources.
You can install Azure PowerShell on your local machine and use it in any PowerShell session. Follow the instructions on the page, to sign in with your Azure credentials, and install the Az PowerShell module.
Connect to Azure with an interactive dialog for sign in
Install-Module -Name Az Connect-AzAccount
Make sure you have the current version of PowerShellGet installed. Run below command and reopen PowerShell.
Install-Module PowerShellGet -Force -AllowClobber
Install Az.FrontDoor module
Install-Module -Name Az.FrontDoor
Create a Front Door profile
Create a Front Door profile by following the instructions described in Quickstart: Create a Front Door profile.
Define geo-filtering match condition
Create a sample match condition that selects requests not coming from "US" using New-AzFrontDoorWafMatchConditionObject on parameters when creating a match condition. Two letter country/region codes to country/region mapping are provided in What is geo-filtering on a domain for Azure Front Door?.
$nonUSGeoMatchCondition = New-AzFrontDoorWafMatchConditionObject ` -MatchVariable RemoteAddr ` -OperatorProperty GeoMatch ` -NegateCondition $true ` -MatchValue "US"
Add geo-filtering match condition to a rule with Action and Priority
Create a CustomRule object
nonUSBlockRule based on the match condition, an Action, and a Priority using New-AzFrontDoorWafCustomRuleObject. A CustomRule can have multiple MatchCondition. In this example, Action is set to Block and Priority to 1, the highest priority.
$nonUSBlockRule = New-AzFrontDoorWafCustomRuleObject ` -Name "geoFilterRule" ` -RuleType MatchRule ` -MatchCondition $nonUSGeoMatchCondition ` -Action Block ` -Priority 1
Add rules to a policy
Find the name of the resource group that contains the Front Door profile using
Get-AzResourceGroup. Next, create a
geoPolicy policy object containing
nonUSBlockRule using New-AzFrontDoorWafPolicy in the specified resource group that contains the Front Door profile. You must provide a unique name for the geo policy.
The following example uses the Resource Group name myResourceGroupFD1 with the assumption that you've created the Front Door profile using instructions provided in the Quickstart: Create a Front Door article. In the below example, replace the policy name geoPolicyAllowUSOnly with a unique policy name.
$geoPolicy = New-AzFrontDoorWafPolicy ` -Name "geoPolicyAllowUSOnly" ` -resourceGroupName myResourceGroupFD1 ` -Customrule $nonUSBlockRule ` -Mode Prevention ` -EnabledState Enabled
Link WAF policy to a Front Door frontend host
Link the WAF policy object to the existing Front Door frontend host and update Front Door properties.
To do so, first retrieve your Front Door object using Get-AzFrontDoor.
$geoFrontDoorObjectExample = Get-AzFrontDoor -ResourceGroupName myResourceGroupFD1 $geoFrontDoorObjectExample.FrontendEndpoints.WebApplicationFirewallPolicyLink = $geoPolicy.Id
Next, set the frontend WebApplicationFirewallPolicyLink property to the resourceId of the
Set-AzFrontDoor -InputObject $geoFrontDoorObjectExample
You only need to set WebApplicationFirewallPolicyLink property once to link a WAF policy to a Front Door frontend host. Subsequent policy updates are automatically applied to the frontend host.