page_title: About Docker page_description: Introduction to Docker. page_keywords: docker, introduction, documentation, about, technology, understanding, Dockerfile
Develop, Ship and Run Any Application, Anywhere
Docker is a platform for developers and sysadmins to develop, ship, and run applications. Docker lets you quickly assemble applications from components and eliminates the friction that can come when shipping code. Docker lets you get your code tested and deployed into production as fast as possible.
Docker consists of:
Faster delivery of your applications
Deploy and scale more easily
Get higher density and run more workloads
Faster deployment makes for easier management
The Understanding Docker section will help you:
The installation section will show you how to install Docker on a variety of platforms.
To learn about Docker in more detail and to answer questions about usage and implementation, check out the Docker User Guide.
Version 1.1.0
.dockerignore
support
You can now add a .dockerignore
file next to your Dockerfile
and Docker will ignore files and directories specified in that file when sending the build context to the daemon. Example: https://github.com/dotcloud/docker/blob/master/.dockerignore
Pause containers during commit
Doing a commit on a running container was not recommended because you could end up with files in an inconsistent state (for example, if they were being written during the commit). Containers are now paused when a commit is made to them. You can disable this feature by doing a docker commit --pause=false <container_id>
Tailing logs
You can now tail the logs of a container. For example, you can get the last ten lines of a log by using docker logs --tail 10 <container_id>
. You can also follow the logs of a container without having to read the whole log file with docker logs --tail 0 -f <container_id>
.
Allow a tar file as context for docker build
You can now pass a tar archive to docker build
as context. This can be used to automate docker builds, for example: cat context.tar | docker build -
or docker run builder_image | docker build -
Bind mounting your whole filesystem in a container
/
is now allowed as source of --volumes
. This means you can bind-mount your whole system in a container if you need to. For example: docker run -v /:/my_host ubuntu:ro ls /my_host
. However, it is now forbidden to mount to /.
Port allocation has been improved. In the previous release, Docker could prevent you from starting a container with previously allocated ports which seemed to be in use when in fact they were not. This has been fixed.
A bug in docker save
was introduced in the last release. The docker save
command could produce images with invalid metadata. The command now produces images with correct metadata.
Running docker inspect
in a container now returns which containers it is linked to.
Parsing of the docker commit
flag has improved validation, to better prevent you from committing an image with a name such as -m
. Image names with dashes in them potentially conflict with command line flags.
The API now has Improved status codes for start
and stop
. Trying to start a running container will now return a 304 error.
Performance has been improved overall. Starting the daemon is faster than in previous releases. The daemon’s performance has also been improved when it is working with large numbers of images and containers.
Fixed an issue with white-spaces and multi-lines in Dockerfiles.