I'm going to take a wild guess that the issue is because vivid's nginx- common.postinst has this line:
invoke-rc.d nginx start || exit $? Which will make postinst fail if nginx fails to start for the first time. 15.04: http://bazaar.launchpad.net/~ubuntu- branches/ubuntu/vivid/nginx/vivid/view/head:/debian/nginx-core.postinst 14.04 did not have this behaviour: http://bazaar.launchpad.net/~ubuntu- branches/ubuntu/trusty/nginx/trusty/view/head:/debian/nginx- common.postinst -- You received this bug notification because you are a member of Ubuntu Server Team, which is subscribed to nginx in Ubuntu. https://bugs.launchpad.net/bugs/1483923 Title: dpkg-divert breaks nginx installation To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/nginx/+bug/1483923/+subscriptions -- Ubuntu-server-bugs mailing list Ubuntu-server-bugs@lists.ubuntu.com Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/ubuntu-server-bugs