Container Tidbits: Understanding the docker-latest Package

Does your team want to move as quickly as possible? Are you and your development team looking for the latest features and not necessarily optimizing on stability? Are you just beginning with the docker runtime and not quite ready for container orchestration? Well, we have the answer, and it’s called the docker-latest package.

Background

About 6 months ago, Red Hat added a package called docker-latest. The idea is to have two packages in Red Hat Enterprise Linux and Red Hat Enterprise Linux Atomic Host. A very fast moving docker-latest package and a slower, but more stable package called, well of course, docker.

The reasoning is, the larger and more sophisticated your container infrastructure becomes, a more stable version is often what people want - but when split into small agile teams, or when just starting out, many teams will optimize on the latest features in a piece of software. Either way, we have you covered with Red Hat Enterprise Linux and Red Hat Enterprise Linux Atomic Host.

Red Hat Enterprise Linux and Red Hat Enterprise Linux Atomic

Red Hat offers two great version of Red Hat Enterprise Linux - Red Hat Enterprise Linux Atomic Host is a minimal host specifically optimized for container workloads, while Red Hat Enterprise Linux is a flexible choice for teams that need a full Linux distribution.

The latest versions are shown below:

Red Hat Enterprise Linux Atomic Host 7.2.7

atomic host status
State: idle
Deployments:
* rhel-atomic-host-ostree:rhel-atomic-host/7/x86_64/standard
Version: 7.2.7 (2016-09-09 18:43:35)
Commit: 347c3f5eb641e69fc602878c646cf42c4bcd5d9f36847a1f24ff8f3ec80f17b1
OSName: rhel-atomic-host
rhel-atomic-host-ostree:rhel-atomic-host/7/x86_64/standard
Version: 7.2.5 (2016-06-18 15:21:12)
Commit: 9bfe1fb65094d43e420490196de0e9aea26b3923f1c18ead557460b83356f058
OSName: rhel-atomic-host

Red Hat Enterprise Linux Atomic Host 7.2.7

cat /etc/redhat-release Red Hat Enterprise Linux Server release 7.2 (Maipo)

Checking the Package Versions

The New docker-latest Package

This is the package which is delivered to provide teams with the latest version of the docker container runtime. The target is projects and teams that prioritize features over stability and integration with a larger platform. This package is delivered with Red Hat Enterprise Linux, and baked into the OSTree for Red Hat Enterprise Linux Atomic Host. Currently, this version is docker 1.12.1:

Red Hat Enterprise Linux Atomic Host 7.2.7

rpm -qi docker-latest
Name        : docker-latest
Version     : 1.12.1
Release     : 2.el7
Architecture: x86_64
Install Date: Fri 09 Sep 2016 02:37:41 PM EDT
Group       : Unspecified
Size        : 122023273
License     : ASL 2.0
Signature   : RSA/SHA256, Thu 01 Sep 2016 10:11:37 AM EDT, Key ID 199e2f91fd431d51
Source RPM  : docker-latest-1.12.1-2.el7.src.rpm
Build Date  : Tue 30 Aug 2016 01:25:15 PM EDT
Build Host  : x86-037.build.eng.bos.redhat.com
Relocations : (not relocatable)
Packager    : Red Hat, Inc. <http://bugzilla.redhat.com/bugzilla>
Vendor      : Red Hat, Inc.
URL         : https://github.com/projectatomic/docker
Summary     : Automates deployment of containerized applications
Description :
Docker is an open-source engine that automates the deployment of any
application as a lightweight, portable, self-sufficient container that will
run virtually anywhere.
Docker containers can encapsulate any payload, and will run consistently on
and between virtually any server. The same container that a developer builds
and tests on a laptop will run at scale, in production*, on VMs, bare-metal
servers, OpenStack clusters, public instances, or combinations of the above.

Red Hat Enterprise Linux 7.2

rpm -qi docker-latest
Name        : docker-latest
Version     : 1.12.1
Release     : 2.el7
Architecture: x86_64
Install Date: Sun 30 Oct 2016 01:06:44 PM EDT
Group       : Unspecified
Size        : 122023273
License     : ASL 2.0
Signature   : RSA/SHA256, Thu 01 Sep 2016 10:11:37 AM EDT, Key ID 199e2f91fd431d51
Source RPM  : docker-latest-1.12.1-2.el7.src.rpm
Build Date  : Tue 30 Aug 2016 01:25:15 PM EDT
Build Host  : x86-037.build.eng.bos.redhat.com
Relocations : (not relocatable)
Packager    : Red Hat, Inc. <http://bugzilla.redhat.com/bugzilla>
Vendor      : Red Hat, Inc.
URL         : https://github.com/projectatomic/docker
Summary     : Automates deployment of containerized applications
Description :
Docker is an open-source engine that automates the deployment of any
application as a lightweight, portable, self-sufficient container that will
run virtually anywhere.
Docker containers can encapsulate any payload, and will run consistently on
and between virtually any server. The same container that a developer builds
and tests on a laptop will run at scale, in production*, on VMs, bare-metal
servers, OpenStack clusters, public instances, or combinations of the above.

You'll note, of course, that the package for Red Hat Enterprise Linux and Red Hat Enterprise Linux Atomic Host are identical, as we use the same packages to build Atomic Hosts as we do standard Red Hat Enterprise Linux.

The Standard docker Package

This is the package which is relied on for api/abi stability and provides the foundation for OpenShift Container Platform. Nothing has changed with this package and it will continue to provide a standard container runtime for Red Hat Enterprise Linux, and Red Hat Enterprise Linux Atomic Host. Currently, this version is docker 1.10.3:

Red Hat Enterprise Linux Atomic Host 7.2.7

rpm -qi docker
Name        : docker
Version     : 1.10.3
Release     : 46.el7.14
Architecture: x86_64
Install Date: Fri 09 Sep 2016 02:37:26 PM EDT
Group       : Unspecified
Size        : 46250859
License     : ASL 2.0
Signature   : RSA/SHA256, Thu 01 Sep 2016 10:11:34 AM EDT, Key ID 199e2f91fd431d51
Source RPM  : docker-1.10.3-46.el7.14.src.rpm
Build Date  : Mon 29 Aug 2016 02:01:16 PM EDT
Build Host  : x86-020.build.eng.bos.redhat.com
Relocations : (not relocatable)
Packager    : Red Hat, Inc. <http://bugzilla.redhat.com/bugzilla>
Vendor      : Red Hat, Inc.
URL         : https://github.com/docker/docker
Summary     : Automates deployment of containerized applications
Description :
Docker is an open-source engine that automates the deployment of any
application as a lightweight, portable, self-sufficient container that will
run virtually anywhere.

Docker containers can encapsulate any payload, and will run consistently on
and between virtually any server. The same container that a developer builds
and tests on a laptop will run at scale, in production*, on VMs, bare-metal
servers, OpenStack clusters, public instances, or combinations of the above.

Red Hat Enterprise Linux 7.2

rpm -qi docker
Name        : docker
Version     : 1.10.3
Release     : 55.el7
Architecture: x86_64
Install Date: Tue 04 Oct 2016 09:46:44 AM EDT
Group       : Unspecified
Size        : 57326501
License     : ASL 2.0
Signature   : RSA/SHA256, Wed 28 Sep 2016 02:30:14 AM EDT, Key ID 199e2f91fd431d51
Source RPM  : docker-1.10.3-55.el7.src.rpm
Build Date  : Mon 19 Sep 2016 09:30:28 AM EDT
Build Host  : x86-017.build.eng.bos.redhat.com
Relocations : (not relocatable)
Packager    : Red Hat, Inc. <http://bugzilla.redhat.com/bugzilla>
Vendor      : Red Hat, Inc.
URL         : https://github.com/docker/docker
Summary     : Automates deployment of containerized applications
Description :
Docker is an open-source engine that automates the deployment of any
application as a lightweight, portable, self-sufficient container that will
run virtually anywhere.
Docker containers can encapsulate any payload, and will run consistently on
and between virtually any server. The same container that a developer builds
and tests on a laptop will run at scale, in production*, on VMs, bare-metal
servers, OpenStack clusters, public instances, or combinations of the above.

Using docker-latest

If you want to use docker-latest on the regular, you're probably going to get tired of typing docker-latest instead of just using docker. You can change the service running docker, by using the following commands:

# systemctl stop docker
# systemctl disable docker
# systemctl enable docker-latest
# systemctl start docker-latest

You also want to change the client command to use docker-latest, so uncomment this line (or add it, if it's not there) in /etc/sysconfig/docker:

DOCKERBINARY=/usr/bin/docker-latest

You do want to make sure that you do this before starting any containers, otherwise your results may be inconsistent.

Conclusion

So, whether you are looking for a fast moving, quick to deliver features, container host, or the most stable Linux platform available, check out Red Hat Enterprise Linux Atomic Host and Red Hat Enterprise Linux.

We have added a new packaging option for those teams that want speed and we still deliver the standard package for those that need to integrate a stack of software in a container platform, such as OpenShift, at scale. If you are interested in a deeper understanding of the docker-latest package, check out the Red Hat Portal Knowledge Base article: Introducing docker-latest for RHEL and RHEL Atomic Host.

As always, leave questions or comments below...