irule for 503 response to client

To issue a redirect when the pool is down, specify a Fallback Host in the HTTP profile.

 

 

I have just uploaded an iRule that improves on this behavior, because the Fallback Host behavior is not ideal. See http://devcentral.f5.com/wiki/default.aspx/iRules/Webserver_Down_Message.html

 

 

As I point out on that page, though, 503 is the magic status code that makes the code fail. Can anyone shed some light on this bug?

+1 : it seems that a public web site must return a 503 error page instead of a 302 (as the BigIP does), because 302 are followed by bots, which means that a maintenance period can ruin some rankings.

 

 

Has anyone made some progress on how to force BigIP redirect using 503 response code ?

 

 

Tx.

In a simple test on 9.4.6, I was able to send a 503 with content using HTTP::respond. I've also used a 503 in 9.2.4 and 9.3.1. I'm not sure if it was a bug in an older version or a configuration issue. But if you're seeing a problem with sending a 503, can you post the iRule you're testing and the results of the tests?

 

 

 
 when HTTP_REQUEST { 
  
    set data {Some data to send to the client.  If you want to use variables in here, replace the curly braces with quotes.} 
  
     Look for a URI starting with a forward slash and then 3 digits (the first digit being 1-5) 
     If one is found, set it as the HTTP response code.  Else, send back an HTTP 200 
    if {[string match {/[1-5][0-9][0-9]*} [HTTP::path]]}{ 
  
        Send the response with the status code from the requested path and data 
       HTTP::respond [string range [HTTP::path] 1 3] content $data "a_header_name" "a_header_value" 
       log local0. "Sending [string range [HTTP::path] 1 3] response with $data" 
    } else { 
        Send a 200 response with data 
       HTTP::respond 200 content $data "a_header_name" "a_header_value" 
       log local0. "Sending default 200 response with $data" 
    } 
 } 
 

 

 

Example curl request:

 

 

 

curl -v 10.42.2.102/503

 

* About to connect() to 10.42.2.102 port 80

 

* Trying 10.42.2.102... connected

 

* Connected to 10.42.2.102 (10.42.2.102) port 80

 

> GET /503 HTTP/1.1

 

> User-Agent: curl/7.15.3 (i686-redhat-linux-gnu) libcurl/7.15.3 OpenSSL/0.9.7l zlib/1.1.4

 

> Host: 10.42.2.102

 

> Accept: */*

 

>

 

< HTTP/1.0 503 Service Unavailable

 

< a_header_name: a_header_value

 

* HTTP/1.0 connection set to keep alive!

 

< Connection: Keep-Alive

 

< Content-Length: 109

 

Connection 0 to host 10.42.2.102 left intact

 

* Closing connection 0

 

Some data to send to the client. If you want to use variables in here, replace the curly braces with quotes.

 

 

 

 

Aaron

Tx for the quick reply. In the mean time, we managed to have the fallback host respond with a 503 code, which would solve the mentioned problem (plus an additional in the HTML code). Nevertheless, I keep a bookmark on this iRule, and I'll let you know if/when I need to put it in place.