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Chris_Miller's avatar
Chris_Miller
Icon for Altostratus rankAltostratus
Apr 22, 2010

iRule for Cookie Removal

I have 2 DCs fronted by a software GTM solution. When a user makes a request, GTM checks to see if they have a "DC" cookie. If they don't, it round robins the request. In the event that DC1 gets the request, the F5 there sets a cookie named "DC" with the value "1" and a server cookie for server-persistency. That way, GTM looks at the cookie and gets DC persistency. If a DC goes bad, GTM will send the request to the other DC even though the cookie exists. So, the F5 at DC2 may see a cookie named "DC" with the value of "1". If that happens, I want the F5 at DC2 to remove the cookie. Am I on the right track here? 
when HTTP_REQUEST {
set strDC [HTTP::cookie "DC"]
if { $strDC equals "1"} {
HTTP::cookie remove "DC"
HTTP::cookie remove "server"
}
}
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iRules
  • hoolio's avatar
    hoolio
    Icon for Cirrostratus rankCirrostratus
    Apr 22, 2010
    If you want the client to delete a cookie you'd need to tell it to in the response. Using HTTP::cookie remove in HTTP_REQUEST is going to remove the cookie from the request that is proxied to the pool--it wouldn't have any effect on the client.

    Can you try this? 

    
when HTTP_REQUEST {
   if {[HTTP::cookie "DC"] eq "1"}{
      set remove_cookies 1
   } else {
      set remove_cookies 0
   }
}
when HTTP_RESPONSE {

   if {$remove_cookies}{
      HTTP::cookie remove "DC"
      HTTP::cookie remove "server"
   }
}

    Aaron
  • The_Bhattman's avatar
    The_Bhattman
    Icon for Nimbostratus rankNimbostratus
    Apr 22, 2010
    Hi Cript2000,

    If I am following your logic you want to remove the cookie from the client context?

    If so then you would need to use the HTTP_RESPONSE event.

    Here is the untested iRule 

     
when HTTP_REQUEST {
 set the value for location in the cookie 
 set StrDC [HTTP::cookie "DC"] 
}
when HTTP_RESPONSE {  
 checks to see if there is a 1 or a cookie header with no value
 if { ($StrDC== "1") or {$StrDC==""  } {
     HTTP::cookie remove "DC"
     HTTP::cookie remove "server"
 }
}

    I hope this helps

    Bhattman

  • Chris_Miller's avatar
    Chris_Miller
    Icon for Altostratus rankAltostratus
    Apr 23, 2010
    Thanks guys - totally blanked and forgot I'd have to send it in the response. :-P

     

     

    Much appreciated!
  • Rami_307440's avatar
    Rami_307440
    Icon for Nimbostratus rankNimbostratus
    Aug 31, 2017

    You can insert a new session and that will overwrite the current one.

    when HTTP_REQUEST {

   set logOut 0
        if {(([HTTP::uri] ends_with "logout")} 
        {
         set logOut 1
        }
            }

when HTTP_RESPONSE {
  if { $logOut == 1 }
  {

    set session_key "whatever0928340923any"

                HTTP::cookie insert name "DC" value $session_key
                HTTP::cookie insert name "server" value $session_key

}