title: What raises HTTP 503 and how to change timeout?
body: <p>I have inherited an application (internal to my company) that uses javascript running in Internet Explorer which makes Ajax calls to a Struts-based application running in WebLogic Server v10.</p>
  
  <p>Certain server-side operations in the system are taking longer than 3 minutes.  Users consistently noticed that the Ajax call returns 503 error at the 3 minute mark.  My users can wait longer than 3 minutes, but 503 errors interrupt their work.</p>
  
  <p>This application needs to be performance tuned, but we badly need a temporary workaround to extend how much time can occur before a 503 error is returned.  </p>
  
  <p>The current theory is that the 503 error is being raised by the IE XMLHttpRequest object.  A team of supposed WebLogic experts poured over our code and WebLogic logs, and declared that there's no timeout occurring on the server side.  But I have my doubts.</p>
  
  <p>My question is, which piece of software is responsible for raising 503 error: the browser, the Ajax javascript, or the server?  And can this timeout period be changed?</p>