Lets an origin accept requests from just one particular Front Door instance, since this HTTP header carries the ID of the Front Door profile.
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Terms in this definition
- Origin
Host behind Front Door that serves the content, such as an App Service app, storage, a load balancer or any custom host given by FQDN. An App Service app counts as one origin regardless of its worker count.
- HTTP
Hypertext Transfer Protocol, which sends data in clear text; VCF interfaces and APIs instead use HTTPS.
Related terms
- AzureFrontDoor.Backend
Service tag for the IP addresses Front Door uses when contacting origins. Pairing it with a filter on the X-Azure-FDID header in an access restriction ensures only your own Front Door instance gets through.
- RequestHeader
Match variable for WAF custom rules that examines a particular request header by name, such as X-Azure-FDID.