What type of "IPv6 Auto configuration" do you mean? In most cases you don't want any kind of auto configuration on your network gear. Depending on the size of your network, what one tends to do at one point (when you don't want to ssh/telnet into all the devices anymore ;) is create a repository with configurations (which are auto generated) and push configurations from a central location. RANCID comes to mind. Of course it all depends on what you want to accomplish and in the end most people tend to write their own management systems which are integrated with their customer backend.