iRule for logging x-forwarded-for header

F5 Rocks,

Your request isn't 100% clear but here is something to get started...

Logging

To log out the X-Forwarded-For header

log local0. "X-Forwarded-For: [HTTP::header X-Forwarded-For]"

Data Group of IPs

Create a Data Group of type Address (for this example called client_ip_class) and add the IP addresses of interest. Use something like the following to check if an address exists in the Data Group

if { [class match [IP::client_addr] equals client_ip_class] } {
    The client IP address is in the class file client_ip_class
     Do something here...
}

Hope this helps.