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rkt is a new container runtime for applications, intended to meet the most demanding production requirements of security, efficiency and composability. rkt is also an implementation of the emerging Application Container (appc) specification, an open specification defining how applications can be run in containers. Today we are announcing the next major release of rkt, v0.5, with a number of new features that bring us closer to these goals, and want to give an update on the upcoming roadmap for the rkt project.

As you might already know, we’re launching our first ever CoreOS Fest this May 4th and 5th in San Francisco! We’ve been hard at work making sure that this event is two days filled with all things distributed, and all things awesome.

“What makes a cluster a cluster?” - Ask that question of 10 different engineers and you’ll get 10 different answers. Some look at it from a hardware perspective, some see it as a particular set of cloud technologies, and some say it’s the protocols exchanging information on the network.

Today we are announcing rkt v0.4.1. rkt is a new app container runtime and implementation of the App Container (appc) spec. This milestone release includes new features like private networking, an enhanced container lifecycle, and unprivileged image fetching, all of which get us closer to our goals of a production-ready container runtime that is composable, secure, and fast.

Our CoreOS Alpha channel is designed to strike a balance between offering early access to new versions of software and serving as the release candidate for the Beta and Stable channels. Due to its release-candidate nature, we must be conservative in upgrading critical system components (e.g. systemd and etcd), but in order to get new technologies (like fleet and flannel) into the hands of users for testing we must occasionally include pre-production versions of these components in Alpha.

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Get ready, CoreOS Fest, our celebration of everything distributed, is right around the corner! Our first CoreOS Fest is happening May 4 and 5, 2015 in San Francisco. You’ll learn more about application containers, container orchestration, clustering, devops security, new Linux, Go and more.

At CoreOS, we want to make the world successful with containers on all computing platforms. Today, we are taking one step closer to that goal by announcing, with VMware, that CoreOS is fully supported and integrated with both VMware vSphere 5.5 and VMware vCloud Air. Enterprises that have been evaluating using containers but needed fully supported environments to begin now have the support to get started.

Today Logentries announced a CoreOS integration, so CoreOS users can get a a deeper understanding into their CoreOS environments. The new integration enables CoreOS users to easily send logs using the Journal logging system, part of CoreOS’ Systemd process manager, directly into Logentries for real-time monitoring, alerting, and data visualization. This is the first CoreOS log management integration.

March brings a variety of events – including a keynote from Alex Polvi (@polvi), CEO of CoreOS, at Rackspace Solve. Read on for more details on the team’s whereabouts this month.

In case you missed it, Alex keynoted at The Linux Foundation Collab Summit last month. See the replay.


Tuesday, March 3, 2015 at 6 p.m. EST – Montreal, QC

A core principle of the App Container (appc) specification is that it is open: multiple implementations of the spec should exist and be developed independently. Even though the spec is young and pre-1.0, it has already seen a number of implementations.

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