Suppose it is Ubuntu Trusty (14.04) release, which has 0.9.1 officially
Update to latest release like 1.7.1
Since 1.7.1 version, it is officially supported using specific apt source. see blog:new APT and YUM repos, I copied the short version here, and use trusty as sample
Add apt source
# add the new gpg key
$ apt-key adv --keyserver hkp://p80.pool.sks-keyservers.net:80 --recv-keys 58118E89F3A912897C070ADBF76221572C52609D
# edit your /etc/apt/sources.list.d/docker.list
$ vim /etc/apt/sources.list.d/docker.list
# remove the contents and replace with the following depending on your os and version:
# Ubuntu Trusty
deb https://apt.dockerproject.org/repo ubuntu-trusty main
Then you can smoothly upgrade to latest docker version
$ apt-get update
# remove the old
$ apt-get purge lxc-docker*
# install the new
$ apt-get install docker-engine
And in the case that you don't want to install latest package then you can do something like below.
$ apt-get install docker-engine=1.7.1-0~trusty
Below is the old information for reference
Update to latest release(now 1.1.1)
This is the way stated to install docker for 12.04 LTS in official document and noticed in ubuntuupdates.org, which looks work for 14.04 as well.
Refer the command to Getting Docker Installed on Ubuntu 12.04 LTS as well
$ wget -qO- https://get.docker.io/gpg | sudo apt-key add -
$ sudo sh -c "echo deb http://get.docker.io/ubuntu docker main > /etc/apt/sources.list.d/docker.list"
$ sudo apt-get update
$ sudo apt-get install lxc-docker
Now I get
$ docker -v
Docker version 1.1.1, build bd609d2
lxc-docker will remove old
docker package, therefore please backup the configuration in advance.
Update to 0.11.1 release
If you want to upgrade in this release, see new launchpad https://launchpad.net/~docker-maint/+archive/testing, better use ppa installation.
sudo add-apt-repository ppa:docker-maint/testing
sudo apt-get update
sudo apt-get install docker.io
Now I get the latest one
$ docker -v
Docker version 0.11.1, build fb99f99
Be aware, with the 1.0 GA release, this method may be changed