[atomic-devel] CentOS Atomic Host 7.1802 Available for Download

[Jason Brooks <jbrooks redhat com>]

The CentOS Atomic SIG has released an updated version
(https://wiki.centos.org/SpecialInterestGroup/Atomic/Download) of
CentOS Atomic Host (7.1802), a lean operating system designed to run
Linux containers, built from standard CentOS 7 RPMs, and tracking the
component versions included in Red Hat Enterprise Linux Atomic Host.

This release rolls up all package minor updates that shipped through
the month of February, including, most significantly, a newer version
of rpm-ostree with support for overriding base packages during package
layering operations. (see below for more details)

CentOS Atomic Host includes these core component versions:

* atomic-1.20.1-9.git436cf5d.el7.centos.x86_64
* cloud-init-0.7.9-9.el7.centos.2.x86_64
* docker-1.12.6-71.git3e8e77d.el7.centos.1.x86_64
* etcd-3.2.11-1.el7.x86_64
* flannel-0.7.1-2.el7.x86_64
* kernel-3.10.0-693.17.1.el7.x86_64
* kubernetes-node-1.5.2-0.7.git269f928.el7.x86_64
* ostree-2017.14-2.el7.x86_64
* rpm-ostree-client-2017.11-1.atomic.el7.x86_64

rpm-ostree override

While it's been possible to layer new packages onto the base CentOS
Atomic tree for some time now, overriding existing base packages with
layered alternatives either wasn't possible or was considered
experimental. Version 7.1802 now allows for overriding base packages.

For example, the origin-clients package that includes OpenShift
Origin's "oc" tool conflicts with the kubernetes-client package
included in the base tree. You can use package layering and overrides
to install the openshift-release rpm, remove the conflicting rpms, and
install the origin-clients rpm:


# rpm-ostree install centos-release-openshift-origin
# rpm-ostree override remove kubernetes-client kubernetes-node -r

# rpm-ostree install origin-clients -r

# oc cluster up
Starting OpenShift using openshift/origin:v3.7.0 ...
Pulling image openshift/origin:v3.7.0
...


Download CentOS Atomic Host

CentOS Atomic Host is available as a VirtualBox or libvirt-formatted
Vagrant box, or as an installable ISO, qcow2 or Amazon Machine image.
For links to media, see the [CentOS
wiki](https://wiki.centos.org/SpecialInterestGroup/Atomic/Download).

Upgrading

If you're running a previous version of CentOS Atomic Host, you can
upgrade to the current image by running the following command:


# atomic host upgrade


Release Cycle

The CentOS Atomic Host image follows the upstream Red Hat Enterprise
Linux Atomic Host cadence. After sources are released, they're rebuilt
and included in new images. After the images are tested by the SIG and
deemed ready, we announce them.

Getting Involved

CentOS Atomic Host is produced by the CentOS Atomic SIG
(http://wiki.centos.org/SpecialInterestGroup/Atomic), based on
upstream work from Project Atomic (http://www.projectatomic.io/). If
you'd like to work on testing images, help with packaging,
documentation -- join us!

The SIG meets every two weeks as part of the Project Atomic community
meeting at 16:00 UTC on Monday in the #atomic channel. You'll often
find us in #atomic and/or #centos-devel if you have questions. You can
also join the atomic-devel
(https://lists.projectatomic.io/mailman/listinfo/atomic-devel) mailing
list if you'd like to discuss the direction of Project Atomic, its
components, or have other questions.

Getting Help

If you run into any problems with the images or components, feel free
to ask on the centos-devel
(http://lists.centos.org/mailman/listinfo/centos-devel) mailing list.

Have questions about using Atomic? See the atomic
(https://lists.projectatomic.io/mailman/listinfo/atomic) mailing list
or find us in the #atomic channel on Freenode.