Trying to find a way to delete cookie with a domain name using irule

rajb I believe the following iRule would work for you but please keep in mind that when you compare "GuysOnlineFilter" text it must be that exact text string, so It has to have those capitalized letters otherwise it will not match and it will do nothing. I recommend testing this in a lab evironment or on a test virtual server to ensure it is working as expected before applying to a production virtual server.

when HTTP_REQUEST priority 500 {
  
    foreach a_cookie [HTTP::cookie names] {
        
        set CookieDomain [HTTP::cookie domain ${a_cookie}]

        if { ${a_cookie} == "GuysOnlineFilter" } {

            if { [HTTP::cookie domain ${CookieDomain}] contains ".sq.org" } {
                log local0. "it's working"
                HTTP::cookie remove ${a_cookie}
            }
                       
        }

    }

}

Paulius For example: I have the following irule

when HTTP_REQUEST {
    # Check if we have already deleted the cookies
    if {not [HTTP::cookie exists tracking_cookie]} {
        # Define an array of cookie names to delete
        set cookie_names [list "loadedFromBrowserCache" "_gid" "_ga" "GuysOnlineFilter" "CruisingListingsFilter" "notifycached"]
        # Loop through each cookie name and delete it if it exists in the ".squirt.org" domain
        foreach cookie_name $cookie_names {
            set CookieDomain [HTTP::cookie domain ${cookie_name}]
            log local0. "Domain name is : ${CookieDomain}"
            if {[HTTP::cookie exists ${cookie_name}] and ${CookieDomain} contains ".sq.org"} {
                HTTP::cookie remove ${cookie_name} domain ".sq.org"
            }
        }
        # Set the tracking cookie to ensure we only delete the cookies once
        HTTP::cookie insert name tracking_cookie value "true" domain ".sq.org"
        HTTP::cookie attribute dummy_cookie value "expires" "Sun, 26-Feb-2023 00:00:00 GMT"
        #HTTP::cookie expires tracking_cookie "1676476831"
    }
}

In the tmm log I see the variable as empty 

Feb 15 12:29:11 lb1.ptp.local info tmm2[19397]: Rule /Common/delete_cookie_test <HTTP_REQUEST>: Domain name is :
Feb 15 12:29:11 lb1.ptp.local info tmm2[19397]: Rule /Common/delete_cookie_test <HTTP_REQUEST>: Domain name is :
Feb 15 12:29:11 lb1.ptp.local info tmm2[19397]: Rule /Common/delete_cookie_test <HTTP_REQUEST>: Domain name is :
Feb 15 12:29:11 lb1.ptp.local info tmm2[19397]: Rule /Common/delete_cookie_test <HTTP_REQUEST>: Domain name is :
Feb 15 12:29:11 lb1.ptp.local info tmm2[19397]: Rule /Common/delete_cookie_test <HTTP_REQUEST>: Domain name is :
Feb 15 12:29:11 lb1.ptp.local info tmm2[19397]: Rule /Common/delete_cookie_test <HTTP_REQUEST>: Domain name is :

I tried the above, however, the variable CookieDomain is empty when I try to print it to the log.