Docker 1.12.2 Release Candidate 2 (RC2) comes one week after the unveiling of the first RC milestone, mainly to address more of the bugs and annoyance discovered lately or reported by users since the first point release of the major Docker 1.12 release. As you might know, Docker 1.12 introduced a lot of exciting new features, such as the built-in orchestration and routing mesh, the brand new Swarm Mode, as well as a bunch of networking improvements for better security. And it looks like Docker 1.12.2 will attempt to further improve the Swarm Mode and networking functionalities.