Samesite cookies on 1600's

You cannot fix SameSite cookie issues on 11.6.x with LTM policies - the required feature are not supported.

You will need to use the irule suggested in that article.

However, if your pool members have addressed the SameSite cookie attributes, then that irule may not be needed.

If the BigIP is adding cookies to the response (persistence cookies, ASM cookies, APM portal cookies), then those cookies will not have the correct attributes set.

In this case, you need to that irule, but the event needs to be HTTP_RESPONSE_RELEASE

BigIP cookies are added after HTTP_RESPONSE (which is just the response from the pool member), so to modify the BigIP cookies, you need to change them just before the final response is released to the client.

when HTTP_RESPONSE_RELEASE {
    # Set-Cookie header can occur multiple times, treat as list
    set num [HTTP::header count Set-Cookie]
    if {$num > 0} {
        foreach set_cookie [HTTP::header values Set-Cookie] {
            # only modify if header does not have SameSite attribute
            set foundSameSite [string match -nocase "*SameSite*" $set_cookie ]
            if {[expr {!$foundSameSite} ]} {
                set set_cookie [concat $set_cookie "; SameSite"]
            }
            # collect modified and unmodified values in list newcookies
            lappend newcookies $set_cookie
        }
        if {$num == 1} {
            # overwrite existing
            HTTP::header replace Set-Cookie [lindex $newcookies 0]
        } else {
            # remove and replace
            HTTP::header remove Set-Cookie
            foreach set_cookie $newcookies {
                HTTP::header insert Set-Cookie $set_cookie
            }
        }
    }
}