Cloud Immutability on Metal in the Data Center

Cloud has enabled a create-destroy infrastructure process that is now seen as common, e.g.  launching and destroying virtual machines and containers. This process is referred to as immutable infrastructure and until now, has not been available to operators within a data center. RackN technology is now actively supporting customers in enabling immutability within a data center on physical infrastructure.

In this post, I will highlight the problems faced by operators in deploying services at scale and introduce the immutability solution available from RackN. In addition, I have added two videos providing background on this topic and a demonstration showing an image deployment of Linux and Windows on RackN using this methodology.


Traditional data center operations provision and deploy services to a node before configuring the application. This post-deployment configuration introduces mutability into the infrastructure due to dependency issues such as operating system updates, library changes, and patches. Even worse, these changes make it incredibly difficult to rollback a change to a previous version should the update cause an issue.

Looking at patch management highlights key problems faced by operators. Applying patches across multiple nodes may lead to inconsistent services with various dependency changes impacted not just by the software but also the hardware. The ability to apply these patches require root access to the nodes which leaves a security vulnerability for an unauthorized login.


Moving the configuration of a service before deployment solves the problems discussed previously by delivering a complete runnable image for execution. However, there is some initialization that is hardware dependent and should only be run once (Cloud-Init) allowing a variety of hardware to be used.

This new approach moves the patching stage earlier in the process allowing operators to ensure a consistent deployment image without the possibility of drift, security issues as no root access is required, as well as simplifying the ability to instantly and quickly move backwards to a previously running image.


In this presentation, Rob Hirschfeld makes the case of immutable infrastructure on bare metal within your data center using RackN technology. Rob delivers the complete story highlighted in this blog post.


In this demonstration, Rob Hirschfeld and Greg Althaus do a complete immutable image deployment of a Linux server and a Windows server using the RackN Portal in less than 20 minutes.

Get started with RackN today to learn more about how you can change your model to this immutability approach.

  • Join the Digital Rebar Community to learn the basics of the Digital Rebar Provision
  • Create an account on the RackN Portal to simplify DRP installation and management
  • Join the RackN Trial program to obtain access to advanced RackN features

Immutable Infrastructure Delivery on Metal : See RackN at Data Center World



The RackN team is heading to San Antonio, TX next week for Data Center World, March 12 – 15. Our co-founder/CEO Rob Hirschfeld is giving a talk on immutable infrastructure for bare metal in the data center (see session information below).

We are interested in meeting and talking with fellow technologists. Contact us this week so we can setup times to meet at the event. If you are able to attend Rob’s session be sure to let him know you saw it here on the RackN blog.

RackN Session

March 12 at 2:10pm
Room 206AM
Session IT7
Tracks: Cloud Services, Direct Access

Operate your Data Center like a Public Cloud with Immutable Infrastructure

The pressure on IT departments to deliver services to internal customers is considerably higher today as public cloud vendors are able to operate on a massive scale, forcing CIOs to challenge their own staff to raise the bar in data center operation. Of course, enterprise IT departments don’t have the large staff of an AWS or Azure; however, the fundamental process running those public clouds is now available for consumption in the enterprise. This process is called “immutable infrastructure” and allows servers to be deployed 100% ready to run without any need for remote configuration of access. It’s called immutable because the servers are deployed from images produced by CI/CD process and destroyed after use instead of being reconfigured. It’s a container and cloud pattern that has finally made it to physical. In this talk, we’ll cover the specific process and its advantages over traditional server configuration.

We’re talking Immutable Containers at Container World





RackN is attending next week’s Container World in Santa Clara, CA and looks forward to talking not just Containers, but image-based provisioning, immutable infrastructure, DevOps, and other topics. Rob Hirschfeld and Shane Gibson are attending and speaking on Wednesday in two sessions (see below).

We are interested in meeting and talking with fellow technologists. Contact us this week so we can setup times to meet at the event.

Rob and Shane are also presenting next Wed the 28th at the Downtown San Jose DevOps Meetup at 6:30pm. The topic is Building Immutable Kubernetes Clusters.


Keeping up with patches has never been more critical.  For hardware, that’s… hard.  What if servers were deployed 100% ready to run without any need for remote configuration or access?  What if we were able to roll a complete rebuild of an entire application stack from the BIOS up in minutes?  Those are key concepts behind a cloud and container deployment pattern called “immutable infrastructure.”  It’s called immutable because the servers are deployed from container images produced by CI/CD process and destroyed after use instead of being reconfigured.  It’s a container and cloud pattern that has finally made it to physical.

In this talk, we’ll cover the specific process and its advantages over traditional server configuration. Then we’ll dive deeply into open tools and processes that make it possible to drive immutable containers into your own infrastructure. The talk will include live demos and will discuss process and field challenges that attendees will likely face when they start implementation at home.  We’ll also cover the significant security, time and cost benefits of this approach to make pitching the idea effective.

Join us for a spirited discussion engineering containers for security, touching on such topics as:

  • The security implications/value of containers on VM or Bare Metal, and is one model significantly more secure than another
  • What are the implications for one vs. the other relative to application portability?
  • Role of immutable infrastructure in managing services and software deployments in the context of security.
  • Is there an automation strategy that makes the portability question moot, or is it still an issue?
  • Security via policy and automation and how do we achieve that automation?
  • How it impacts to portability? Is it better than, or an alternative to automation?

RackN talks Cloud Native Landscape on Rishidot.TV

Rob Hirschfeld speaks on Rishidot.TV  as part of the Cloud Native Landscape video interview series. Questions asked:

  • Background on RackN
  • Cloud Native Ecosystem Fit – embracing DevOps and Site Reliability Engineering
    • Running “Cloud” in their existing data centers
  •  Differentiation – Build on open source Digital Rebar replacing Cobbler, Maas, and other provisioning tools
    • API driven, Infrastructure as Code feel
  • Use Cases –  Immutable Infrastructure & API driven design
    • Image-based Deployments direct to Metal
    • CI/CD infrastructure, zero-touch automation


Full Stack Physical Provisioning Automation: Metal to Platform Delivery

RackN and the Digital Rebar community are focused on solving key issues learned from enterprise DevOps teams:

  1. Operations are inconsistent, manual and heterogeneous
  2. Foundational automation makes many problems go away
  3. “Apply, Rinse, Repeat” (aka Immutable Infrastructure)

The learnings from these experiences led the RackN founders to analyze the current state of the provisioning to platform marketplace which is currently a jumble of disconnected tools that have been architected and released over the past 20 to 30 years. As you can see in the diagram below, there exists an Integration Gap between the limited number of Provision/Control tools and a large selection of Orchestration/Platforms.

This Integration Gap presents significant challenges to DevOps teams looking to deploy a variety of platforms with their chosen Orchestration tool. We seamlessly integrate the Control and Provision layer with any Orchestration or Platform chosen providing a single foundational platform to manage your infrastructure.

With a solid foundation built on Digital Rebar and RackN, operators can proactively choose how far up the stack they wish to deploy without being locked in from old tools. For example, Digital Rebar can simply provision a Windows or Linux OS, an Ansible or Chef environment, or continue up the stack to a complete Kubernetes Cluster.

This flexibility from a single Provision and Control platform meets the needs of operators faced with complexity in heterogeneous infrastructure, clouds, and edge computing. This foundation enables IT to take advantage of new deployment concepts such as Immutable Infrastructure.  

Get started today with our 30-day trial to see how Digital Rebar and RackN can automate your provisioning and control technology to meet the rapidly accelerating demands on internal IT teams.

RackN and Digital Rebar Philosophy of Provisioning

Re-defining physical automation to make it highly repeatable and widely consumable while also meeting the necessarily complex and evolving heterogeneous data center environment is the challenge the RackN team is solving. To meet this challenge, we have developed a unique philosophy in how we build our technology; both open source Digital Rebar and the additional RackN packages.

  • Stand-alone Provisioning
  • Building Software from the API
  • Single Golang Executable
  • Modular Components – Composable Content
  • Operator Defined Workflows
  • Immutable Infrastructure
  • Distributed or Consolidated Architectures

Stand-alone Provisioning

It is critical that Digital Rebar Provision (DRP) provides operators the maximum flexibility in terms of where to run the service (Server, Top-of-Rack Switch, ARM, Intel, etc) as well as removal of any dependencies that might restrict its deployment.  Each environment has it’s own unique Infrastructure DNA; the hardware, operating systems, and application stacks that drive the Infrastructure underlay.

Building Software from the API

The Digital Rebar Provision solution is built with an API first mentality.  Features and enhancements are implemented as an API (making it a first-class citizen), and the CLI is dynamically generated from the API which insures 100% coverage of API implementations within the CLI.  

This methodology also allows for the CLI to directly follow the structure and syntax of the API, making it easy for an Operator or Developer to understand and flexibly interchange the API and CLI syntax.  

At RackN we believe in strongly in the 12-Factor App methodology for designing modern software.  DRP is a direct reflection of these principles.

Single Golang Executable

DRP is built with Golang which is a modern Procedural language that is easily cross-compiled for multiple operating systems and processor architectures.  As a benefit, the DRP service and CLI tool (dr-provision and drpcli respectively) can run on platforms that range from small Raspberry Pi embedded systems, network switches at the Top-of-Rack, huge Hyper Converged Infrastructure (HCI) servers, to everything in between.  It is currently compiled and runs on Linux (arm, intel, 32 bit, and 64 bit), Mac OS X (64 bit), and Windows (64 bit).

The dr-provision binary is very small and lightweight, requiring almost zero external dependencies.  Current external dependencies are unzip, pk7zip, and bsdtar, and these dependencies should be removed in a future version.  At only 30 MByte in size, it requires fairly little resources to run.  

Modular Components ~ Composable Content

Modular architecture allows us to create complex solutions from a set of simple building blocks that offer functionality that is well tested. Breaking complex problems down in to small components, and then allowing strong templating capabilities creates a structure that allows for strong reuse patterns.   This approach permeates all of the “Content” components that create the foundational building blocks for composable provisioning activities.  

Operator Defined Workflows

Each environment has a unique set of services, applications, tooling, and practices for managing the Infrastructure.  Taking the concepts of Composable Content, we allow an operator or developer a flexible structure in which they have control in determining how loosely or tightly to integrate the DRP provisioning services in to their environment.  Every customer environment has a unique set of tools, and this methodology allows for smooth integration with those operational principles

Immutable Infrastructure    

Maintaining hardware and software in a massive data center or cloud is a significant challenge without the additional overhead of ensuring that patches are properly applied. Any changes to an active solution can introduce complications on a live system which is a major barrier to having security updates and other patches completed in a timely manner.

A better method is to only deploy a “golden image” to the live system and rather than patch each individual instance, simply tear down the instance and replace with a new copy of the “golden image.”  All patches can be applied and tested to create a new golden image which is easily rolled out in the create – destroy- re-create model of  immutability.

Distributed or Consolidated Architectures

Traditional data center and lab environments utilize centralized provisioning services.  While DRP has strong support for this scale-up or consolidated model, shifting patterns in application and service deployment topology dictates an evolving provisioning service solution.  Current Internet-of-Things (IoT), Edge, and Fog architectures distribute resources across disperse environments.

In the traditional model, a large scale operator might support a handful of datacenters with 10s of thousands of hosts in each facility.   These new trending architecture patterns can encompass 1000s of different locations, each hosting a few dozen to a few hundred hosts.  This shift creates significant burden on operational and infrastructure management tooling to support the complexities of these scale-out designs.

With strong multi-endpoint management tooling, the RackN portal can easily support both models for provisioning.  Long-lived scale-up environments with a service that is updated, upgraded, managed, loved, and cared for can exist seamlessly alongside environments with a create/destroy pattern that treats 1000s of provisioning endpoints as disposable assets.

Podcast – Year of the Crawfish Recap and 2018 Predictions for Bare Metal, Virtualization, Edge and Serverless

Welcome to the final L8istSh9y Podcast for 2017 with a recap of Rob Hirschfeld’s predictions for 2017 (2016 Infrastructure Revolt makes 2017 the “year of the IT Escape Clause”) as well as a look ahead into 2018. Key topics covered in the podcast:

  • Hybrid is Reality; How do I Cope with it?
  • Site Reliability Engineering; People are Just Doing it
  • Bare Metal to Immutable Images
  • Virtualization Decline with Bare Metal Growth
  • 2018 is not the Year of Serverless
  • Edge Computing Still Not Ready for Prime Time
  • OpenStack Foundation as Open Infrastructure Group

Topic                                                       Time (Minutes.Seconds)

Introduction                                               0.0 – 1.50
2017 ~ Year of Crawfish                           1.50 – 3.00  (Summary)
Hybrid Mainstream                                  3.00 – 7.30
Site Reliability Engineering                    7.30 – 12.45 (Cloud Native Infrastructure Book)
RackN Changed Focus to Bare Metal  12.45 – 13.50
Bare Metal to Immutable                       13.50 – 17.03
Decline of Virtualization                         17.03 – 21.47  (ARM Servers)
Serverless – Not in 2018                         21.47 – 22.57
Edge Computing                                      23.16 – 26.39
OpenStack Foundation                           26.39 – 32.55
Wrap Up                                                    32.55 – END


Thank you for joining us in the past few months in launching our new Podcast focused on DevOps, Site Reliability Engineering, Operators, Infrastructure, Edge Computing, Cloud Computing and other related topics. Please contact us if you are looking for information on a specific topic for a future podcast or if you are interested in participating as a guest.

Podcast Home Page – L8istSh9y Podcast
YouTube Videos of Audio Podcasts – Playlist

Webinar: Immutable Kubernetes with RackN Provisioning

Watch this webinar to learn more about the RackN Kubernetes installation integration using community tools like Kubeadm demonstrated at this week’s KubeCon event (Slides) in Austin, TX. Co-Founders Rob Hirschfeld and Greg Althaus of RackN will discuss this fast and simple approach to operating Kubernetes. Of course, we’ll also demonstrate the technology installing Kubernetes following the immutable infrastructure model highlighting the automated provisioning technology built on the open source Digital Rebar project.

After this webinar, you’ll be prepared to attempt this install strategy on your own.

Why attend this webinar?
* Benefits of the Immutable Infrastructure provisioning model
* Solve installation issues with Kubernetes using community Kubeadm tooling
* Overview of the RackN + Digital Rebar automated provisioning solution

Rob Hirschfeld : CEO/Co-Founder, RackN
Greg Althaus : CTO/Co-Founder, RackN

Day & Time:

Dec 14, 2017 1:30 PM CST

Watch the Webinar on YouTube

Data Center’s Last Mile: Zero Touch Metal Automation

The embedded video is an excellent RackN and Digital Rebar overview created by Rob Hirschfeld and Greg Althaus, co-founders of RackN on the critical issue facing data center operations teams. Their open-source based offering completes the integration challenge existing between platforms/orchestration tools and control/provision technology.

By integrating with the platform and orchestration solutions, RackN is able to replace the control and provisioning tools without adding complexity or replacing established technology.

Watch the complete video below as Rob Hirschfeld provides the background of how RackN arrived at the current offering and the benefits for data center operators to support bare metal provisioning as well as immutable infrastructure. (Slides)

The demonstration video referenced in this overview:

The white paper referenced in this overview:








Have more questions? Contact us at or via social media on Twitter at @rackngo to learn more.

Podcast: David Linthicum on Reality of Cloud, DevOps, and Industry Trends

Rob Hirschfeld, CEO/Co-Founder of RackN speaks with David Linthicum, an internationally known cloud computing and SOA expert and Sr VP at Cloud Technology Partners. Rob and David cover a variety of IT topics in this podcast including a Buck Rodgers quote from David.

TOPIC                                                             TIME

Introduction & Ask Podcaster                     0:00 – 3:20
Lack of Skillsets in IT                                    3:20 – 5:43
Accumulation of Technical Debt                5:43 – 10:57
DevOps and Automation                              10:57 – 14:08
CI and CD                                                        14:08 – 15:48
When Not Go CI and CD                              15:48 – 18:00
What to pay attention to in cloud?             18:00 – 20:17
How select right cloud tech?                       20:17 – 23:49
Hybrid is best of breed tech                        23:49 – 25:39
Are Containers the silver bullet?                25:39 – 29:14
Serverless vs Containers                             29:14 – 33:16
Kubernetes – Meso – Docker Opinion     33:16 – 36:04
Predictions and Trends                                36:04 – 37:10
Edge Computing                                           37:10 – 38:25
Wrap Up – where to find David L.             38:25 – END



Podcast Guest – David Linthicum @DavidLinthicum

Dave Linthicum is Sr. VP at Cloud Technology Partners, and an internationally known cloud computing and SOA expert. He is a sought-after consultant, speaker, and blogger. In his career, Dave has formed or enhanced many of the ideas behind modern distributed computing including EAI, B2B Application Integration, and SOA, approaches and technologies in wide use today. In addition, he is the Editor-in-Chief of SYS-CON’s Virtualization Journal.

For the last 10 years, he has focused on the technology and strategies around cloud computing, including working with several cloud computing startups. His industry experience includes tenure as CTO and CEO of several successful software and cloud computing companies, and upper-level management positions in Fortune 500 companies. In addition, he was an associate professor of computer science for eight years, and continues to lecture at major technical colleges and universities, including University of Virginia and Arizona State University. He keynotes at many leading technology conferences, and has several well-read columns and blogs. Linthicum has authored 10 books, including the ground-breaking “Enterprise Application Integration” and “B2B Application Integration.” You can reach him at Or follow him on Twitter. Or view his profile on LinkedIn.