Using a web browser, browse to and click the Free Download link: GNS3 v2.1.9 is the last version that runs on OS X version 10.11 (El Capitan).įollow these steps to download GNS3 to you MAC. GNS3 supports OS X Lion (version 10.12) and later. This document explains how to install GNS3 using when a Mac OS X environment. Configure GNS3 to use an additional remote server.