Settings mapped between Azure Front Door (classic) and Standard/Premium tier

Important

Azure Front Door (classic) will be retired on March 31, 2027. To avoid any service disruption, it is important that you migrate your Azure Front Door (classic) profiles to Azure Front Door Standard or Premium tier by March 2027. For more information, see Azure Front Door (classic) retirement.

When you migrate your Azure Front Door (classic) to Azure Front Door Standard or Premium, you'll notice some configurations have been either changed, or relocated to provide a better experience when managing your Front Door profile. In this article you'll learn how routing rules, cache duration, rules engine configuration, WAF policy and custom domains are mapped in the new Front Door tier.

Routing rules

Front Door (classic) settings Mapping in Front Door Standard and Premium
Route status - enable/disable Changes to Enable route with checkbox. Location remains the same.
Accepted protocol Copied from Front Door (classic) profile.
Frontend/domains Changes to Domains. Copied from Front Door (classic) profile.
Patterns to match Copied from Front Door (classic) profile.
Rules engine configuration The rules engine configuration name changes to rule set but will retain its association to routes from the Front Door (classic) profile.
Route type: Forwarding Backend pool changes to origin group. Forwarding protocol is copied from the Front Door (classic) profile.
- If URL rewrite is set to disabled, the origin path in Standard or Premium profile is blank.
- If URL rewrite is set to enabled, the Custom forwarding path of the Front Door (classic) profile is set as the origin path.
Route type: Redirect A URL redirect rule set gets created called URLRedirectMigratedRuleSet1 with a URL redirect rule.

Cache duration

In Azure Front Door (classic), the Minimum cache duration is configured in the routing rules settings and the Use default cache duration is set in the Rules engine configuration. Azure Front Door Standard and Premium only supports changing caching duration in a Rule set rule.

Front Door (classic) Mapping in Front Door Standard and Premium
Caching is disabled and default caching is used. Caching is set to disabled.
Caching is enabled and the default caching duration is used. Caching is set to enabled, the origin caching behavior is honored.
Caching is enabled and minimum caching duration is set. Caching is set to enabled and the cache behavior is set to override always with the minimum cache duration from Front Door (classic).
N/A Caching is set to enabled. The caching behavior is set to override if the origin is missing, and the input cache duration gets used.

Route configuration override in rules engine configuration

The route configuration override in a rules engine configuration action for Front Door (classic) is split into three different actions in a Rule set rule for Azure Front Door Standard and Premium. Those three actions are URL redirect, URL rewrite and route configuration override.

Actions in rules engine configuration Mapping in Front Door Standard and Premium
Route type set to Forward 1. If URL rewrite is disabled, all settings are copied over to the Standard or Premium profile.
2. If URL rewrite is enabled, two rule actions will be created. One for URL rewrite and one for the route configuration override setting. For the URL rewrite action, the custom forwarding path in Front Door (classic) profile is set to the destination.
Route type set to Redirect URL redirect action settings are copied over.
Route configuration override Backend pool is mapped to an origin group. Enabling caching remains the same. Query string is mapped to query string caching behavior, dynamic compression is mapped to compression.
Use default cache duration For more information, see cache duration section.

Other configurations

Front Door (classic) configuration Mapping in Front Door Standard and Premium
Request and response header Request and response header in Rules engine actions is copied over to Rule set.
Enforce certificate name check Enforce certificate name check is supported at the profile level of an Azure Front Door (classic). In Azure Front Door Standard or Premium profile this setting can be found in the origin settings. This configuration gets applied to all origins in the migrated profile.
Origin response time Origin response time gets copied over to the migrated profile.
Web Application Firewall (WAF) If the Azure Front Door (classic) profile has WAF policies associated, the migration will create a copy of each WAF policy for the respective tier migrating to. Names for each WAF policy can be changed during prepare phase of the migration. You can also select an existing Front Door Standard or Premium WAF policy that matches the migrated Front Door profile.
Custom domain This section will use www.contoso.com as an example to show what happens to a domain going through the migration. The custom domain www.contoso.com points to contoso.azurefd.net in the Front Door (classic) as a CNAME record.

When www.contoso.com gets moved to the new Front Door profile:
- The association for the custom domain shows the new Front Door endpoint as contoso-<hashvalue>.z01.azurefd.net. The CNAME of the custom domain will automatically point to the new endpoint name with the hash value in the backend. At this point, you can change the CNAME record with your DNS provider to point to the new endpoint name with the hash value.
- The classic endpoint contoso.azurefd.net will show as a custom domain in the migrated Front Door profile under the Migrated domain tab of the *Domains page. This domain will be associated to the default migrated route. This default route can only be removed once the domain is disassociated from it. The domain properties can't be updated, except for when associating and removing the association from a route. The domain can only be deleted after you've changed the CNAME to the new endpoint name.
- The certificate state and DNS state for www.contoso.com will be consistent as the Front Door (classic) profile.

No changes are made the managed certificate auto rotation settings.

Next steps