Return status code and a retry after X value

Hi DarkSide,

 

 

You can use HTTP::respond to send a specific response code and append a list of header names and values. I think something like this should work:

 

 

when HTTP_REQUEST {

    Check if the User-Agent header 
   if {[HTTP::header User-Agent] contains "some user-agent string"}{

       Send a 503 response with a Retry-After header set to 5 minutes
       Don't include the Server: BigIP header (noserver)
       Retry-After described in: http://tools.ietf.org/html/rfc2616section-14.37
      HTTP::respond 503 noserver "Retry-After" 300
   }
}

 

 

Aaron

Hi Hoolio,

 

 

I appreciate the assistance. I wasn't sure about appending the "Retry-After" header after I had the 503 in there. I had to modify the Retry-After part as it wouldn't accept it (I'm running 9.2.4 if that makes a difference?)

 

 

Here is what I got working if someone comes across the need for something like this as I did.

 

 

when HTTP_REQUEST {

 

Check the User-Agent header

 

switch -glob [string tolower [HTTP::header User-Agent]] {

 

"*msnbot*" -

 

"*fast-*" -

 

"*yahoo-newscrawler*" -

 

"*baiduspider*" -

 

"*google*" {

 

Send a 503 response with a Retry-After header set to 3 hours

 

Don't include the Server: BigIP header (noserver)

 

HTTP::respond 503 noserver Retry-After:10800

 

}

 

}

 

}

When you say it doesn't work, do you mean that the Retry-After header isn't set in the response? Else, can you try testing with curl from the LTM command line:

curl -v --user-agent "google" http://1.1.1.1/

Can you replace the colon with a space in Retry-After 10800:

when HTTP_REQUEST {
   HTTP::respond 503 noserver Retry-After 3
}

> GET /test.123 HTTP/1.1

> User-Agent: curl/7.15.5 (i686-redhat-linux-gnu) libcurl/7.15.5 OpenSSL/0.9.8b zlib/1.2.3 libidn/0.6.5

> Host: 7.7.7.18

> Accept: */*

>

< HTTP/1.0 503 Service Unavailable

< Retry-After: 3

< Connection: Keep-Alive

< Content-Length: 0

Aaron

Sorry, I just notice you said you're running 9.2.x. The noserver flag was added in 9.4 to remove the Server: BigIP header. You can use this instead:

when HTTP_REQUEST {
   HTTP::respond 503 Retry-After 3
}

Aaron

When I tried to use "Retry-After" 10800 the LTM threw an error when creating the new iRule, so I changed that to "Retry-After:10800" and it accepted it.

 

 

I've changed my HTTP:RESPOND line to this, we'd like them to come back in 3 hours.

 

 

HTTP::respond 503 Retry-After 10800

 

 

Does that look OK?

That's exactly it.

 

 

Aaron

Excellent!!!

 

 

Once again Hoolio...many thanks to you!