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 1.3.0
This version fixes a number of bugs and issues and adds new functions and other improvements. The GitHub 1.3 milestone has more detailed information. Major additions and changes include:
New command: docker exec
The new docker exec
command lets you run a process in an existing, active
container. The command has APIs for both the daemon and the client. With
docker exec
, you'll be able to do things like add or remove devices from
running containers, debug running containers, and run commands that are not
part of the container's static specification. Details in the command line
reference.
New command: docker create
Traditionally, the docker run
command has been used to both create a
container and spawn a process to run it. The new docker create
command breaks
this apart, letting you set up a container without actually starting it. This
provides more control over management of the container lifecycle, giving you the
ability to configure things like volumes or port mappings before the container
is started. For example, in a rapid-response scaling situation, you could use
create
to prepare and stage ten containers in anticipation of heavy loads.
Details in the command line reference.
Tech preview of new provenance features
This release offers a sneak peek at new image signing capabilities that are
currently under development. Soon, these capabilities will allow any image
author to sign their images to certify they have not been tampered with. For
this release, Official images are now signed by Docker, Inc. Not only does this
demonstrate the new functionality, we hope it will improve your confidence in
the security of Official images. Look for the blue ribbons denoting signed
images on the Docker Hub.
The Docker Engine has been updated to automatically verify that a given
Official Repo has a current, valid signature. When pulling a signed image,
you'll see a message stating the image you are pulling has been verified
. If
no valid signature is detected, Docker Engine will fall back to pulling a
regular, unsigned image.
Other improvements & changes
We've added a new security options flag to the docker run
command,
--security-opt
, that lets you set SELinux and AppArmor labels and profiles.
This means you'll no longer have to use docker run --privileged
on kernels
that support SE Linux or AppArmor. For more information, see the
command line reference.
A new flag, --add-host
, has been added to docker run
that lets you add
lines to /etc/hosts
. This allows you to specify different name
resolution for the container than it would get via DNS. For more information,
see the command line reference.
You can now set a DOCKER_TLS_VERIFY
environment variable to secure
connections by default (rather than having to pass the --tlsverify
flag on
every call). For more information, see the https guide.
Three security issues have been addressed in this release: CVE-2014-5280, CVE-2014-5270, and CVE-2014-5282.