OpenCrowbar Design Principles: Reintroduction [Series 1 of 6]

While “ready state” as a concept has been getting a lot of positive response, I forget that much of the innovation and learning behind that concept never surfaced as posts here.  The Anvil (2.0) release included the OpenCrowbar team cataloging our principles in docs.  Now it’s time to repost the team’s work into a short series over the next three days.

In architecting the Crowbar operational model, we’ve consistently twisted adapted traditional computer science concepts like late binding, simulated annealing, emergent behavior, attribute injection and functional programming to create a repeatable platform for sharing open operations practice (post 2).

Functional DevOps aka “FuncOps”

Ok, maybe that’s not going to be the 70’s era hype bubble name, but… the operational model behind Crowbar is entering its third generation and its important to understand the state isolation and integration principles behind that model is closer to functional than declarative programming.

Parliament is Crowbar’s official FuncOps sound track

The model is critical because it shapes how Crowbar approaches the infrastructure at a fundamental level so it makes it easier to interact with the platform if you see how we are approaching operations. Crowbar’s goal is to create emergent services.

We’ll expore those topics in this series to explain Crowbar’s core architectural principles.  Before we get into that, I’d like to review some history.

The Crowbar Objective

Crowbar delivers repeatable best practice deployments. Crowbar is not just about installation: we define success as a sustainable operations model where we continuously improve how people use their infrastructure. The complexity and pace of technology change is accelerating so we must have an approach that embraces continuous delivery.

Crowbar’s objective is to help operators become more efficient, stable and resilient over time.

Background

When Greg Althaus (github @GAlhtaus) and Rob “zehicle” Hirschfeld (github @CloudEdge) started the project, we had some very specific targets in mind. We’d been working towards using organic emergent swarming (think ants) to model continuous application deployment. We had also been struggling with the most routine foundational tasks (bios, raid, o/s install, networking, ops infrastructure) when bringing up early scale cloud & data applications. Another key contributor, Victor Lowther (github @VictorLowther) has critical experience in Linux operations, networking and dependency resolution that lead to made significant contributions around the Annealing and networking model. These backgrounds heavily influenced how we approached Crowbar.

First, we started with best of field DevOps infrastructure: Opscode Chef. There was already a remarkable open source community around this tool and an enthusiastic following for cloud and scale operators . Using Chef to do the majority of the installation left the Crowbar team to focus on

crowbar_engineKey Features

  • Heterogeneous Operating Systems – chose which operating system you want to install on the target servers.
  • CMDB Flexibility (see picture) – don’t be locked in to a devops toolset. Attribute injection allows clean abstraction boundaries so you can use multiple tools (Chef and Puppet, playing together).
  • Ops Annealer –the orchestration at Crowbar’s heart combines the best of directed graphs with late binding and parallel execution. We believe annealing is the key ingredient for repeatable and OpenOps shared code upgrades
  • Upstream Friendly – infrastructure as code works best as a community practice and Crowbar use upstream code
  • without injecting “crowbarisms” that were previously required. So you can share your learning with the broader DevOps community even if they don’t use Crowbar.
  • Node Discovery (or not) – Crowbar maintains the same proven discovery image based approach that we used before, but we’ve streamlined and expanded it. You can use Crowbar’s API outside of the PXE discovery system to accommodate Docker containers, existing systems and VMs.
  • Hardware Configuration – Crowbar maintains the same optional hardware neutral approach to RAID and BIOS configuration. Configuring hardware with repeatability is difficult and requires much iterative testing. While our approach is open and generic, the team at Dell works hard to validate a on specific set of gear: it’s impossible to make statements beyond that test matrix.
  • Network Abstraction – Crowbar dramatically extended our DevOps network abstraction. We’ve learned that a networking is the key to success for deployment and upgrade so we’ve made Crowbar networking flexible and concise. Crowbar networking works with attribute injection so that you can avoid hardwiring networking into DevOps scripts.
  • Out of band control – when the Annealer hands off work, Crowbar gives the worker implementation flexibility to do it on the node (using SSH) or remotely (using an API). Making agents optional means allows operators and developers make the best choices for the actions that they need to take.
  • Technical Debt Paydown – We’ve also updated the Crowbar infrastructure to use the latest libraries like Ruby 2, Rails 4, Chef 11. Even more importantly, we’re dramatically simplified the code structure including in repo documentation and a Docker based developer environment that makes building a working Crowbar environment fast and repeatable.

OpenCrowbar (CB2) vs Crowbar (CB1)?

Why change to OpenCrowbar? This new generation of Crowbar is structurally different from Crowbar 1 and we’ve investing substantially in refactoring the tooling, paying down technical debt and cleanup up documentation. Since Crowbar 1 is still being actively developed, splitting the repositories allow both versions to progress with less confusion. The majority of the principles and deployment code is very similar, I think of Crowbar as a single community.

Continue Reading > post 2

OpenCrowbar.Anvil released – hammering out a gold standard in open bare metal provisioning

OpenCrowbarI’m excited to be announcing OpenCrowbar’s first release, Anvil, for the community.  Looking back on our original design from June 2012, we’ve accomplished all of our original objectives and more.
Now that we’ve got the foundation ready, our next release (OpenCrowbar Broom) focuses on workload development on top of the stable Anvil base.  This means that we’re ready to start working on OpenStack, Ceph and Hadoop.  So far, we’ve limited engagement on workloads to ensure that those developers would not also be trying to keep up with core changes.  We follow emergent design so I’m certain we’ll continue to evolve the core; however, we believe the Anvil release represents a solid foundation for workload development.
There is no more comprehensive open bare metal provisioning framework than OpenCrowbar.  The project’s focus on a complete operations model that comprehends hardware and network configuration with just enough orchestration delivers on a system vision that sets it apart from any other tool.  Yet, Crowbar also plays nicely with others by embracing, not replacing, DevOps tools like Chef and Puppet.
Now that the core is proven, we’re porting the Crowbar v1 RAID and BIOS configuration into OpenCrowbar.  By design, we’ve kept hardware support separate from the core because we’ve learned that hardware generation cycles need to be independent from the operations control infrastructure.  Decoupling them eliminates release disruptions that we experienced in Crowbar v1 and­ makes it much easier to use to incorporate hardware from a broad range of vendors.
Here are some key components of Anvil
  • UI, CLI and API stable and functional
  • Boot and discovery process working PLUS ability to handle pre-populating and configuration
  • Chef and Puppet capabilities including Birk Shelf v3 support to pull in community upstream DevOps scripts
  • Docker, VMs and Physical Servers
  • Crowbar’s famous “late-bound” approach to configuration and, critically, networking setup
  • IPv6 native, Ruby 2, Rails 4, preliminary scale tuning
  • Remarkably flexible and transparent orchestration (the Annealer)
  • Multi-OS Deployment capability, Ubuntu, CentOS, or Different versions of the same OS
Getting the workloads ported is still a tremendous amount of work but the rewards are tremendous.  With OpenCrowbar, the community has a new way to collaborate and integration this work.  It’s important to understand that while our goal is to start a quarterly release cycle for OpenCrowbar, the workload release cycles (including hardware) are NOT tied to OpenCrowbar.  The workloads choose which OpenCrowbar release they target.  From Crowbar v1, we’ve learned that Crowbar needed to be independent of the workload releases and so we want OpenCrowbar to focus on maintaining a strong ops platform.
This release marks four years of hard-earned Crowbar v1 deployment experience and two years of v2 design, redesign and implementation.  I’ve talked with DevOps teams from all over the world and listened to their pains and needs.  We have a long way to go before we’re deploying 1000 node OpenStack and Hadoop clusters, OpenCrowbar Anvil significantly moves the needle in that direction.
Thanks to the Crowbar community (Dell and SUSE especially) for nurturing the project, and congratulations to the OpenCrowbar team getting us this to this amazing place.

 

Mayflies and Dinosaurs (extending Puppies and Cattle)

Dont Be FragileJosh McKenty and I were discussing the common misconception of the “Puppies and Cattle” analogy. His position is not anti-puppy! He believes puppies are sometimes unavoidable and should be isolated into portable containers (VMs) so they can be shuffled around seamlessly. His more provocative point is that we want our underlying infrastructure to be cattle so it remains highly elastic and flexible. More cattle means a more resilient system. To me, this is a fundamental CloudOps design objective.

We realized that the perfect cloud infrastructure would structurally discourage the creation of puppies.

Imagine a cloud in which servers were automatically decommissioned after a week of use. In a sort of anti-SLA, any VM running for more than 168 hours would be (gracefully) terminated. This would force a constant churn of resources within the infrastructure that enables true cattle-like management. This cloud would be able to very gracefully rebalance load and handle disruptive management operations because the workloads are designed for the churn.

We called these servers mayflies due to their limited life span.

While this approach requires a high degree of automation, the most successful cloud operators I have met are effectively building workloads with this requirement. If we require application workloads to be elastic and fault-resilient then we have a much higher degree of flexibility with the underlying infrastructure. I’ve seen this in practice with several OpenStack clouds: operators with helped applications deploy using automation were able to decommission “old” clouds much more gracefully. They effectively turned their entire cloud into a cow. Sadly, the ones without that investment puppified™ the ops infrastructure and created a much more brittle environment.

The opposite of a mayfly is the dinosaur: a server that is so brittle and locked that the slightest disturbance wipes out everything it touches.

Dinosaurs are puppies grown into a T-Rex with rows of massive razor sharp teeth and tiny manicured hands. These are systems that are so unique and historical that there’s no way to recreate them if there’s a failure. The original maintainers exit happy hour was celebrated by people who were laid-off two CEOs ago. The impact of dinosaurs goes beyond their operational risk; they are typically impossible to extend or maintain and, consequently, ossify other server around them. This type of server drains elasticity from your ops team.

Puppies do not grow up to become dogs, they become dinosaurs.

It’s a classic lean adage to do hard things more frequently. Perhaps it’s time to start creating mayflies in your ops infrastructure.

Competition should be core to OpenStack Technical Meritocracy

In my work at Dell, Technical Meritocracy means that we recognize and promote demonstrated talent into leadership roles. As a leader, one has to make technical judgments (OK, informed opinions) that focus limited resources in the (hopefully) right places. Being promoted does not automatically make someone right all the time.

I believe that good leaders recognize the value of a diverse set of opinions and the learning value of lean deliverables.

OpenStack is an amazingly diverse and evolving community. Leading in OpenStack requires a level of humility that forces me to reconsider my organization hierarchical thinking around “technical meritocracy.” Instead of a hierarchy where leadership chooses right and wrong, rising in the community meritocracy is about encouraging technical learning and user participation.

OpenStack is a melting pot of many interests and companies. Some of them naturally aligned (customers+vendors) and others are otherwise competitive (vendors). The vast majority of contribution to OpenStack is sponsored – companies pay people to participate and fund the foundation that organizes events. That does not diminish our enthusiasm for the community or open values, but it adds an additional dimension

If we are really seeking a Technical Meritocracy, we must create a place where ideas, teams, projects and companies can pursue different approaches within OpenStack. This is essential to our long term success because it provides a clear way for people to experiment within the project. Pushing away alternate approaches is likely to lead to forking. Specifically, I believe that the mostly likely competitor to any current OpenStack project will be that project’s .next version!

Calls for a “benevolent dictator” imply that our meritocracy has a single person with perspective on right and wrong. Not only is OpenStack simply too complex, I see our central design tenant as enabling multiple approaches to work it out in the community. This is especially important because many aspects of OpenStack are not one-size-fits all. The target diversity of our community requires that we enable multiple approaches so we can expand our user base.

The risk of anointing a single person, approach or project as “the OpenStack way” may appear to streamline the project, but it really stifles innovation. We have a healthy ecosystem of vendors who gladly express opinions about the right way to implement OpenStack. They help us test OpenStack technical merit by finding out which opinions appeal to users. It is essential to our success to enable a vibrant diversity because I don’t think there’s a single right answer or approach.

In every case, those vendor opinions are based on focused markets and customer needs; consequently, our job in the community is to respect and incorporate these divergent needs and find consensus.

7 takeaways from DevOps Days Austin

Block Tables

I spent Tuesday and Wednesday at DevOpsDays Austin and continue to be impressed with the enthusiasm and collaborative nature of the DOD events.  We also managed to have a very robust and engaged twitter backchannel thanks to an impressive pace set by Gene Kim!

I’ve still got a 5+ post backlog from the OpenStack summit, but wanted to do a quick post while it’s top of mind.

My takeaways from DevOpsDays Austin:

  1. DevOpsDays spends a lot of time talking about culture.  I’m a huge believer on the importance of culture as the foundation for the type of fundamental changes that we’re making in the IT industry; however, it’s also a sign that we’re still in the minority if we have to talk about culture evangelism.
  2. Process and DevOps are tightly coupled.  It’s very clear that Lean/Agile/Kanban are essential for DevOps success (nice job by Dominica DeGrandis).  No one even suggested DevOps+Waterfall as a joke (but Patrick Debois had a picture of a xeroxed butt in his preso which is pretty close).
  3. Still need more Devs people to show up!  My feeling is that we’ve got a lot of operators who are engaging with developers and fewer developers who are engaging with operators (the “opsdev” people).
  4. Chef Omnibus installer is very compelling.  This approach addresses issues with packaging that were created because we did not have configuration management.  Now that we have good tooling we separate the concerns between bits, configuration, services and dependencies.  This is one thing to watch and something I expect to see in Crowbar.
  5. The old mantra still holds: If something is hard, do it more often.
  6. Eli Goldratt’s The Goal is alive again thanks to Gene Kims’s smart new novel, The Phoenix project, about DevOps and IT  (I highly recommend both, start with Kim).
  7. Not DevOps, but 3D printing is awesome.  This is clearly a game changing technology; however, it takes some effort to get right.  Dell brought a Solidoodle 3D printer to the event to try and print OpenStack & Crowbar logos (watch for this in the future).

I’d be interested in hearing what other people found interesting!  Please comment here and let me know.

Crowbar and our Pivot (or, how we slipped and shipped Grizzly)

Crowbar Grizzly PostMy team at Dell uses Lean process because it forces us to be honest about making hard choices. Our recent decision to pivot back to Crowbar 1.x for the OpenStack Grizzly release is a great example how the pivot process works.

4/24 note: I have a longer post and ISO for Grizzly on Crowbar waiting until we enter QA. The Crowbar community is already very active around this work and you’re encouraged to join.

Like any refactor, there was schedule risk when we started the Crowbar 2.x release. To mitigate this risk, we made two critical choices. First, we choose to advance the OpenStack barclamps on the 1.x code base in parallel with the 2.x work. Second, we chose a pivot date for the team to choose releasing Grizzly on the 1.x or 2.x trunks.

Choosing to jump back to 1.x was one of the hardest choices I’ve made in my career. I’m proud that we had the foresight to keep that as an option and prouder that our team rallied to make it happen.

I acknowledge that 1.x has gaps; however, getting Grizzly into the field for PoCs and pilots with 1.x provide substantial benefits to the community.  That said, there are barclamps for HA deployments and other production features that are under development on the 1.x branch and will be available in the community.

The 2.x code base provides important features but we are building from on the 1.x deployment recipes. This means that development, testing and tuning applied to the Grizzly barclamps will translates directly into Crowbar 2.x field readiness. In fact, more completeness on OpenStack can dramatically simplify Crowbar 2.x testing efforts.  This is especially true on the OpenStack Networking (fka Quantum) barclamps because they are new work.

Delivering solutions is a balance between features, timing and field experience.  The Crowbar team’s preference is to collaborate with operators in the field and that means making workable software available quickly.

I hope that you’ll agree with our approach and help us make Grizzly the most deployable OpenStack yet.