Indicates that a request came from Fastly.

Fastly writes this header into requests. It is proprietary to Fastly.

This header is attached to all requests that come from a Fastly server. In practice, this means that in any service that has clustering or shielding enabled, Fastly-Client will be true on all but the first server that received the request. It will also be included on the request forwarded to the backend.

User contributed notes


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