Available inall subroutines.

Returns true if the address family of the given address is IPv4.


if (addr.is_ipv4(client.ip)) {
/* the client connected over IPv4 */

Try it out

addr.is_ipv4 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.

Log the IP version (IPv4/IPv6)

Identify which type of IP address was used by the client connecting to your Fastly service.