<p>The ARN of an IAM service role that Elastic Beanstalk has permission to assume.</p> <p>The <code>ServiceRole</code> property is required the first time that you provide a <code>VersionLifecycleConfig</code> for the application in one of the supporting calls (<code>CreateApplication</code> or <code>UpdateApplicationResourceLifecycle</code>). After you provide it once, in either one of the calls, Elastic Beanstalk persists the Service Role with the application, and you don't need to specify it again in subsequent <code>UpdateApplicationResourceLifecycle</code> calls. You can, however, specify it in subsequent calls to change the Service Role to another value.</p>