When does F5 use Set-Cookie for persistence cookie ?

Hannes Rapp beat me to the SOl. What exactly are you trying to achieve? Looks like cookie rewrite might be your solution but will require some configs on the sending servers.

"The HTTP Cookie Rewrite method requires you to set up the cookie created by the server. For the HTTP Cookie Rewrite method to succeed, there needs to be a blank cookie coming from the web server for the BIG-IP system to rewrite. With Apache variants, the cookie can be added to every web page header by adding the following entry to the httpd.conf file: Header add Set-Cookie BIGipCookie=0000000000000000000000000..."