client.identity

STRING, can be read and set, but not unset.

Available in all subroutines.

This variable is used by the Client director to determine which backend to pick. Given the same client.identity, the same backend will be chosen every time. Defaults to the client IP address.

Try it out

client.identity is used in the following code examples. Examples apply VCL to real-world use cases and can be deployed as they are, or adapted for your own service. See the full list of code examples for more inspiration.

Click RUN on a sample below to provision a Fastly service, execute the code on Fastly, and see how the function behaves.

Client director

Map requests to backends based on user ID (a.k.a., "sticky sessions"). Defaults to IP address but you can customize.