It's actually the same binary - the tutum agent just downloads it and upgrades it when requested. If you had docker already installed using a storage engine different than AUFS, because the tutum agent installer tries to use the AUFS storage engine (way more stable than "devicemapper"), you won't be able to "see" what you had in your previous storage engine. But the binary is the one from https://docs.docker.com/installation/binaries/#get-the-linux...