14.37 Retry-After


The Retry-After response-header field can be used with a 503 (Service Unavailable) response to indicate how long the service is expected to be unavailable to the requesting client. This field MAY also be used with any 3xx (Redirection) response to indicate the minimum time the user-agent is asked wait before issuing the redirected request. The value of this field can be either an HTTP-date or an integer number of seconds (in decimal) after the time of the response.
       Retry-After  = "Retry-After" ":" ( HTTP-date | delta-seconds )


Two examples of its use are
       Retry-After: Fri, 31 Dec 1999 23:59:59 GMT
       Retry-After: 120


In the latter example, the delay is 2 minutes.