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The Observability Pipeline

The rise of cloud and containers has led to systems that are much more distributed and dynamic in nature. Highly elastic microservice and serverless architectures mean containers spin up on demand and scale to zero when that demand goes away. In this world, servers are very much cattle, not pets. This shift has exposed deficiencies in some of the tools and practices we used in the world of servers-as-pets. It has also led to new tools and services created to help us support our systems.

Many of the clients we work with at Real Kinetic are trying to navigate their way through this transformation and struggle to figure out where to begin with these solutions. Beau Lyddon, one of our partners, recently gave a talk on exactly this called What is Happening: Attempting to Understand Our Systems (as an aside, Honeycomb’s Charity Majors live-blogged the talk which is worth a read). In this post, I’m going to attempt to summarize some of the key ideas from Beau’s talk and introduce the concept of an observability pipeline, which we think is an essential component in today’s cloud-native, product-oriented world.

Observability Explosion

With traditional static deployments and monolithic architectures, monitoring is not too challenging (that’s not to say it’s easy, but, in relative terms, it’s uncomplicated). This is where tools like Nagios became very popular. When we have only a handful of servers and/or a single, monolithic application, it’s relatively straightforward to determine the health of the system and to correlate system behavior to actual customer or business impact. It’s also feasible to “see inside the box” and get meaningful code-level instrumentation. Once again, tools like AppDynamics and Dynatrace became popular here.

With cloud-native and container-based systems, instances tend to be highly elastic and ephemeral, and what used to comprise a single, monolithic application might now consist of dozens of different microservices and even different instances running different versions of the same service. Simply put, systems are more distributed, more dynamic, and more complex now than ever before—and users have even more expectations. This means many of the tools that were well-suited before might not be adequate now.

For example, the ability to “see inside the box” with intra-process, code-level tracing becomes largely impractical in a highly dynamic cloud environment. By the time you are debugging an issue, the container is gone. This is only exacerbated by the serverless or functions as a service (FaaS) movement. Similarly, it’s much more difficult to correlate the behavior of a single service to the user’s experience since partial failure becomes more of an everyday thing. Thus, many of these tools end up being better suited to static infrastructures where there is a small set of long-lived VMs with a limited number of services. That’s where most of them originated from anyway. Instead, service-level distributed tracing becomes a key part of microservice observability, as does structured logging. With this shift in how we build systems, there has been an explosion in new terms, new tools, and new services.

Of course, in addition to tools, there are also the cultural aspects of monitoring and incident response. Many companies traditionally rely on an operations team to monitor, triage, and—in some cases—even resolve issues. This model quickly becomes untenable as the number of services increases. A single operations team will not be able to maintain enough context for a non-trivial amount of services and systems to do this effectively. This model also leads to ineffective feedback loops if engineers are not on-call and responsible for the operation of their services—something I’ve talked about ad nauseum. My advice is to push ownership of systems onto the teams who built them. This includes on-call duty and general operational responsibilities. However, in order for development teams to take on this responsibility, they need to be empowered to act on it. With this model, which I’ve come to facetiously call NewOps, the operations team becomes responsible for providing the tools and data teams need to adequately operate their services. Some organizations take this even further with dedicated observability teams.

“Observability” is a term that has emerged recently within the industry as a more nuanced take on traditional monitoring. While monitoring tends to focus more on the overall health of systems and business metrics, observability aims to provide more granular insights into the behavior of systems along with rich context useful for debugging and business purposes. Put another way, monitoring is about known-unknowns and actionable alerts; observability is about unknown-unknowns and empowering teams to interrogate their systems.

In a sense, observability encompasses all of the telemetry needed to gain insight into the behavior and state of a running system. This includes items like application logs, system logs, audit logs, application metrics, and distributed-tracing data. These are all valuable signals for diagnosing and debugging production issues, especially in a microservice environment where containers are largely ephemeral. In this environment, it is no longer practical to SSH into a machine to debug a problem or tail a log file. Distributed tracing becomes particularly important since a single application transaction may invoke multiple service functions.

Observability Pipeline

It’s important that you can really own your data and prevent it from being locked up inside a single vendor’s solution. Likewise, it’s important that data can be made available to the entire enterprise (or, in some cases, made not available to the entire enterprise). Since the number of tools and products can be quite large, tool and data needs vary from team to team, and the overall amount of data can be overwhelming, I suggest a decoupled approach. By building an observability pipeline, we can decouple the collection of this data from the ingestion of it into a variety of systems.

To illustrate, if we have log data going to Splunk, metrics and traces going to Datadog, client events going to Google Analytics and BigQuery, and everything going to Amazon Glacier for cold storage, the number of integrations quickly becomes large and grows for every additional service we add. It also probably means we are running an agent for many of these services on each host, and if any of these services are unavailable or behind, our application either blocks or we lose critical observability data. With the amount of data we end up collecting, it’s not uncommon to spend more time collecting it than actually performing business logic unless we find a way to efficiently get it out of the critical path.

Finally, as vendors in this space converge on features (which they are), differentiating capabilities are released (which they will need), or licensing/pricing issues arise (which they do), it’s likely that the business will need to add or remove SaaS solutions over time. If these are tightly integrated, this can be difficult to do. An observability pipeline, as we will later see, allows us to evaluate multiple solutions simultaneously or replace solutions transparently to applications and infrastructure. For example, perhaps we need to switch from Splunk to Sumo Logic or Datadog to New Relic or evaluate Honeycomb in addition to New Relic. How big of a lift would this be for your organization today? How easy is it to experiment with a new tool or service?

With an observability pipeline, we decouple the data sources from the destinations and provide a buffer. This makes the observability data easily consumable. We no longer have to figure out what data to send from containers, VMs, and infrastructure, where to send it, and how to send it. Rather, all the data is sent to the pipeline, which handles filtering it and getting it to the right places. This also gives us greater flexibility in terms of adding or removing data sinks, and it provides a buffer between data producers and consumers.

There are a few components to this pipeline which I will cover below. Many of the components can be implemented with existing open source tools or off-the-shelf services, so those I will touch on only briefly. Other parts require more involvement and some up-front thinking, so I’ll speak to them in more detail.

Data Specifications

Structured logging is hugely important to aiding debuggability. Anyone who’s shipped production code has been in the situation where they’re frantically trying to regex logs to pull out the information they need to debug a problem. It’s even worse when we’re debugging a request going through a series of microservices with haphazard logging. But structured logging isn’t just about creating better logs, it’s about creating a data pipeline that can feed the many tools you’ll need to leverage to understand, debug, and optimize complex systems, meet security and compliance requirements, and provide critical business intelligence.

In order to monitor systems, debug problems, make decisions, or automate processes, we need data. And we need the systems to give us data to provide necessary context. Aside from structured logging, one piece of advice we give every client is to pass a context object to basically everything. This context includes all of the important metadata flowing through a system—usually IDs that allow you to correlate events and piece together a story of what’s happening inside your system: user ID, account ID, trace ID, request ID, parent ID, and so on. What we want to avoid is the sort of murder-mystery debugging that often happens. A lone error log is the equivalent of finding a body. We know a crime occurred, but how do we piece together the clues to tell the right story? Observability—that is, being able to ask questions of your systems and truly explore them—requires access to pre-aggregate, raw data and support for high-cardinality dimensions.

The way to decide what goes on the context is to think about the data you wish you had while debugging an issue (this also highlights the importance of developers supporting their own systems). What is the data that would change the behavior of the system? Some examples include the user (or company), their license, time, machine stats (e.g. CPU and memory), software version, configuration data, the incoming request, downstream requests, etc. Of these, what can we get for “free” and what do we need to pass along? “Free” in this case would be things which are machine-provided, such as memory and CPU. The data we can’t get for free should go on the context, typically data that is request-specific. This context should be included on every log message.

This brings us back to the importance of structuring your data. To do this, I encourage creating standard specifications for each data type collected—logs, metrics, traces, events, etc. You can take this as far as you’d like—highly structured with a type system and rigid specification—but at a minimum, get logs into a standard format with property tags. JSON is fine for the actual structure, but be sure to version the spec so that it can evolve. For application events, one pattern that can work well is to create an inheritance structure with a base spec that applies across services (e.g. user context and tracing information are the same) and specialized specs that can be defined by services if needed. Just be careful not to leak sensitive data here—this is one area where code reviews are vital.

Specification Libraries

A key part of empowering developers is providing tools that align the “easy” path with the “right” path. If these aren’t aligned, pain-driven development creates problems. In order for developers to take advantage of structured data, specifications aren’t enough. We need libraries which implement the specs and make it easy for engineers to actually instrument their systems. For logging, there are many existing libraries. Just Google “structured logs” and your language of choice. For tracing and metrics, there are APIs like OpenTracing and OpenCensus. In practice, implementing the spec might be a combination of libraries and transformations made by the data collector described below.

Data Collector

This component is responsible for collecting data from hosts, containers, or other sources and writing it to the data pipeline. It may also perform transformations or filtering of data. A couple popular open source solutions for this are Fluentd and Logstash. Typically this runs as a sidecar or agent on the host, and data is written to stdout/stderr or a Unix domain socket, which it then pushes to the pipeline.

Data Pipeline

This component is a highly scalable data stream which can handle the firehose of observability data being generated and has high availability. This also provides a buffer for the data and decouples producers from consumers. Off-the-shelf solutions include Apache Kafka, Google Cloud Pub/Sub, Amazon Kinesis Data Streams, and Liftbridge.

Data Router

This component consumes data from the pipeline, performs filtering, and writes it to the appropriate backends. It may perform some transformations and processing of the data as well, but generally any heavy processing should be the responsibility of a backend system (e.g. alerting or aggregations). This is where the data specifications come into play. The data type will determine how routers handle incoming data, e.g. routing log data to Splunk and cold storage, routing traces to Google Stackdriver, and routing metrics and APM data to New Relic.

Like the specifications and libraries, this is a component that requires some more involvement. The downside of moving away from agent-based data collection is we now have to handle routing that data ourselves. The upside is most vendors provide good APIs and client libraries which make this easier.

Since this is typically a stateless service, it’s a good fit for “serverless” solutions like Google Cloud Functions or AWS Lambda.

Piecing It All Together

Putting all of these pieces together, the observability pipeline looks something like the following:

One caveat I want to point out is that this is not something you need to build out from day one. At most of the companies where we’ve implemented this, it was something that evolved over time. For instance, with some of the clients we work with who are attempting to move to the cloud and adopt DevOps practices, we typically would not advise making a significant upfront investment to architect this pipeline. This is an ideal goal to work towards that will become increasingly important as the amount of services, traffic, and data scales. Instead, architect your systems from the beginning to be able to adopt this approach more easily—use structured logging, keep collection out-of-process, and use a centralized logging system.

For organizations that are heavily siloed, this approach can help empower teams when it comes to operating their software. Unlocking this data can also be a huge win for the business. It provides a layer of abstraction that allows you to get the data everywhere it needs to be without impacting developers and the core system. Lastly, it allows you to change backing data systems easily or test multiple in parallel. With the amount of data and the number of tools modern systems demand these days, the observability pipeline becomes just as essential to the operations of a service as the CI/CD pipeline.

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Scaling DevOps and the Revival of Operations

Operations is going through a renaissance right now. With the move to cloud, the increasing amount of automation, and the increasing importance of automation, Ops as we know it is reinventing itself out of necessity. Infrastructure is becoming more and more sophisticated—and commoditized—and practices are just now starting to grow up around that. So while some worry about robots taking our jobs, the reality is more about how automation will help augment us to build better software and focus on higher-value things. It’s not so much about the distant future—whatever that may hold—so much as it is about the next five to ten years, what Operations looks like in that timeframe, and why I think it has to retool.

When we think about traditional Operations, we probably think about hardware and servers, managing networks and databases, application servers and runtimes, disaster recovery, Nagios checks, as well as the business side—vendor management, procurement, and so on. Finally, we have applications built on top by development teams.

We have a nice, clean separation—developers focus on building features and products, and Ops focuses on making sure the lights stay on. Of course, we know the reality is this separation also creates a lot of problems, so DevOps was borne out of this as a way to bring these two groups into alignment by improving communication and feedback loops.

Now, with the move to cloud, many of these traditional Ops functions are effectively being outsourced to cloud providers, i.e. the idea of NoOps. We get unprecedented elasticity and on-demand compute with far less overhead than we ever had before—shrinking procurement time from days or weeks to seconds or minutes.

What this leaves is a thin but important slice between Google or Amazon and those products built by developers—the glue, essentially, between cloud and product. I call this NewOps (which I use facetiously in reference to NoSQL/NewSQL), and it’s the future of Ops. This encompasses infrastructure automation, deployment automation, configuration management, logging, monitoring, and many other things. When Marc Andreessen said software is eating the world, he really meant it. The future of Ops—and many other things—is software. It’s killing the boring, repetitive things we really don’t want to be doing anyway and letting us shift our focus elsewhere.

Certainly, automation is nothing new and is, I think, an important part of DevOps, so I’m going to explain what I mean by NewOps and why I’m distinguishing it. I also don’t want to mischaracterize by having these neatly delineated Ops models. The truth is, your company doesn’t just one day graduate and gets its DevOps diploma. Instead, it might evolve through various manifestations of these different models. DevOps is a journey, not a destination in and of itself.

I like to think of a DevOps scale of automation, from manual provisioning all the way to fully self-service. Next, I add a second dimension, org size, from the smallest startups to the biggest enterprises.

Scaling DevOps

Scaling a business is probably one of the hardest things a company has to go through. In particular, dealing with the problem of silos. They happen at every company as it grows, but why is it that silos form in the first place?

Many companies start with a “DevOps” approach, often out of necessity more than anything. As a small startup, we can’t afford to have dedicated developers, QA, Ops, and security people. We just have people, and those people wear many different hats. Developers might be pushing their own code to production. They might even be managing the infrastructure that code runs on. There’s probably not a lot of stability, probably a lot of risk, and probably not a whole lot of thought towards controlling costs.

But as the product scales, we specialize. And as the business scales, we add various safety checks, controls, and processes. Developers write code, Ops people run it, QA gets blamed for defects, security blocks everything, and management wonders why nothing gets shipped.

And so we end up in the top left-hand quadrant with Ops as gatekeepers. Ops is fighting for stability and, at the same time, devs are basically fighting for change. More or less, we have a stable, cost-controlled, risk-averse environment—hopefully. But we also have a significant delivery and innovation bottleneck.

Specialization is good! But misalignment is not good. The question is, then, how do we scale specialization? Cross-functional teams come to mind. After all, DevOps encourages cooperation! We add an Ops engineer to each team, and maybe a reliability engineer, and perhaps a few extra for on-call backup, and of course a QA engineer too. Problem solved, right?

But hold on. What if we have 40 development teams? And all those teams are doing microservices. And, of course, all of those microservices are special snowflakes each with their own stacks, infrastructure, databases, and so on. This quickly gets out of control, but moreover, that’s a lot of teams and specialized roles on those teams. That’s a lot of headcount which equates to a lot of hiring and a lot of time and money. If you’re Google and you can just throw money at the problem, this might work out okay. For the rest of us, it might not be such a realistic option.

We go back to the drawing board and again ask ourselves how do we scale specialization? My thought to how we do this is with vision and product.

A vision is simply a mental image of what the future could be like. It enables independent decision making and alignment. Vision allows all of those teams, and the people on those teams, to make decisions without having to constantly coordinate with each other. Without vision, you’re just iterating to nowhere fast.

But vision without execution is just hallucination. Products are how we scale execution. Specifically, this idea of Operations through the lens of product, which I’ll describe after showing the parallel with what’s happening in QA.

In a lot of engineering organizations, many QA roles have been quietly disappearing. I think what’s happening is this evolution of QA, particularly, this shift from being test-focused to tools-focused.

We can look at companies like Amazon and Microsoft who popularized the SDET (Software Development Engineer in Test) model. These companies recognized that having a separate QA and development group causes a lot of problems, just like how having a separate Ops group does. We end up with SDEs (Software Development Engineers) who still focus on the development aspects of building software and SDETs who focus on the quality aspects, but rather than having two wholly separate groups, we just have development teams with SDETs embedded in them.

More recently, Microsoft moved to what they call a “Combined Engineering” model—effectively combining the SDE and SDET roles into a single role called a Software Engineer. Software Engineers write the product code, test code, and tools code needed to deliver their service. They are responsible for everything. Quality is a core concern of software development anyway.

Software Engineers write the code, unit tests, and integration tests. Those tests run in CI. The code moves through a CD pipeline before finally going out to production in some fashion. QA teams are shrinking, but what’s growing are the teams building the tools—the CI environments, the CD pipelines, the automated testing frameworks, the production tooling and automation, etc. The same is becoming true of Ops.

This is what I mean by “Operations through the lens of product.” The build, release, deploy automation, configuration management, infrastructure automation, logging, monitoring—these are all products.

Constraints often make problems easier. At Workiva, as we were struggling through that scaling phase, we placed a constraint on ourselves. We capped our infrastructure engineering headcount at 15% of R&D. This forced us to solve the problem using technology, and technical problems tend to be easier than people problems. In effect, this required us to productize our infrastructure. In doing so, we scaled. We controlled costs. We kept our headcount in check. We reduced risk. We accelerated development. Ultimately, we delivered value to customers faster, going from about three to four releases per year to multiple releases per day. In the end, this is really the goal of DevOps—to deliver value to customers continuously and to do it rapidly and reliably.

Rethinking Ops

It’s time we start to rethink Operations because clearly this model of Ops as cluster or infrastructure admins does not scale. Developers will always out-demand their capacity to supply. Either your headcount is out of control or your ability to innovate and deliver is severely hamstrung. Operations becomes this interrupt-driven thing where we’re just fighting fires as they happen. Ops as masters of production usually devolves to Ops becoming human incident routers, trying to figure out what team or person can help resolve problems because, being responsible for everything, they don’t have the insight to fix it themselves.

Another path that many companies take is Platform as a Service. Workiva is an example of this. For a very long time, Workiva didn’t have a traditional Ops team because the Ops team was Google. The first product was built on Google App Engine. This helped immensely to deliver value to customers quickly. We could just focus on the product and not the surrounding operational aspects, but there is a very real innovation bottleneck that comes with this.

The idea of “Ops lock-in” can be a major problem, whether it’s a PaaS like App Engine locking you in or your own Ops team who just isn’t able to support the kind of innovation that you’re trying to do.

My vision for the future of Operations is taking Combined Engineering to its logical conclusion. Just like with QA, Ops capabilities should be embedded within development teams. The reality is you can’t be an effective software engineer today without some Ops skills, and I think every role should be working towards automating itself out of a job. Specifically, my vision is enabling developers to self-service through tooling and automation and empowering them to deploy and operate their services.

The knee-jerk reaction to this idea is usually fully embracing Infrastructure as a Service, infrastructure as code, and giving developers freedom—and usually the consequences are dire. The point here is that the pendulum can swing too far in the other direction. This was a problem for a brief period of time at Workiva. As we were building new products off of App Engine, developers had this newfound freedom, so teams all went different directions introducing new tech, new infrastructure, new services, and so forth. It was a free-for-all, an explosion of stuff, and the cost explosion that comes with it.

There has to be some control around that, so we tweak the vision statement a bit: enabling developers to self-service through tooling and automation and empowering them to deploy and operate their services…with minimal Ops intervention. We have to have some checks and balances in place.

With this, Ops become force multipliers. We move away from the reactive, interrupt-driven model where Ops are masters of production responsible for everything. Instead, we make dev teams responsible for their services but provide the tools they need to actually own their systems end-to-end—from the code on their laptops to operating it in production.

Enabling developers to self-service through tooling and automation means treating Ops as a product team. The infrastructure automation, deployment automation, configuration management, logging, monitoring, and production tools—these are all products. It’s these products that allow teams to fully own their services. This leads to empowerment.

I have this theory that all engineering organizations operate in this fashion which I call pain-driven development. As a company grows, it starts to develop limbs—teams or silos. Each of these limbs has its own pain receptors. Teams operate in a way that minimizes the amount of pain that they feel, it’s human instinct. We make locally optimal decisions to minimize pain and end up following a path of least resistance.

Silos promote pain displacement, which results in a “bulkhead” effect. Product development feels the pain of building software, QA feels the pain of testing software, and Ops feels the pain of running software. This creates broken feedback loops. For instance, developers aren’t feeling the pain Ops is feeling trying to run their software. We just throw things over the wall and it becomes an empathy problem.

This leads to misaligned incentives because each team will optimize for the pain that they feel. How do you expect developers to care about quality if they’re not on the hook? Similarly, how do you expect them to care about operability if they’re not on the hook? Developers won’t build truly reliable software until they are on-call for it and directly responsible. However, responsibility requires empowerment. You can’t have one without the other. You can’t ask someone to care about something and fix it without also giving them the power to do so. Most Ops teams simply haven’t done enough to empower and offload responsibility onto development teams.

Products enable ownership. We move away from Ops as masters of production responsible for everything and push that responsibility onto dev teams. They are the experts for their services. They are best equipped to deal with problems that arise. But we provide the tools they need to diagnose and resolve those problems on their own.

Products maintain control through enablement—enabling teams to follow best practices for builds, testing, deploys, support, and compliance. Compliance and other SDLC requirements have to be encoded into the tools and processes. These are things developers won’t empathize with or simply won’t understand. Rather than giving them a long list of things they have to do, we take as many of those things as we can and bake them into our products. If you use these tools or follow these processes, you’ll get a lot of this stuff for free. This reduces risk and accelerates development.

Similarly, we can’t allow all of the special snowflakes to happen. We have to control that explosion of stuff. To do this, we use pain-driven development to our advantage by creating paths of least resistance. Using standardized patterns, application shapes, and infrastructure services, we can setup “paths” to both make it easier to reach production and meet the goals of the business. As a developer, if you follow this path, your life will be a lot easier and you’ll feel less pain. If you deviate from that path, things get much harder—and painful.

We end up with a set “menu” of standard application shapes and infrastructure. If teams want to deviate and go off-menu, it’s on them to make a case for it. For example, if I want to introduce Erlang into our stack, it’s on my team and me to present the case for that. Part of this might mean we help build and maintain the tools needed to support that. If there is a compelling enough case or enough teams are making similar asks, we can start to standardize new shapes.

Note that we aren’t necessarily mandating technologies, but we’re leveraging pain-driven development to work in our favor.

Products in Practice

Next, I’m going to look at this idea of Operations through the lens of product in a bit more detail. We’ll see what this might actually look like in practice, again using Workiva as a bit of a case study.

Below is the high-level flow that I think about, from code on laptop to code in production.

Starting with the Build and continuous integration stage, this workflow tends to look something like the following. A developer pushes a change to a branch in a code repository, e.g. GitHub. This triggers a few things to happen. First, the build process, which runs unit/integration tests and builds artifacts. This, in turn, might trigger a QA and/or compliance process. At the same time, we have code reviews happening. All of these processes provide feedback to the developer to quickly iterate.

Workiva has a lot of automated processes built into the developer workflow, some off-the-shelf and some built in-house. For example, when a PR is opened, a security scanner runs which does static analysis and looks for various security vulnerabilities. This can flag a security review when a closer look is needed. Likewise, there is code coverage, automated builds, unit tests, and integration tests, Docker image builds, and compliance checks. The screenshots below come from an open-source repo showing some of these products in practice.

For compliance reasons, Workiva requires at least one other person sign-off on code changes. GitHub provides pretty good support for this. Code reviewers provide their feedback, developers work through that feedback, and, once satisfied, reviewers give their “plus one.”

The screenshot below shows some of the automated processes Workiva relies on in the developer workflow: Travis CI, Codecov, Smithy (which is Workiva’s internal build system), Skynet (automated testing), Rosie (automated compliance controls, e.g. do you have code reviews, security reviews, other SDLC compliance requirements?), and Aviary (the security scanner). Once all of these have passed, the PR is automatically labeled with “Merge Requirements Met” and the change can be merged into master.

There are a couple things worth pointing out with this workflow. First, the build plan is part of the code and not baked into some build tool. This allows dev teams to fully control their builds. Second, you noticed that Workiva has very deep integration with GitHub. This has allowed them to build automated controls into the development process, which speeds up the developer’s workflow while reducing risk.

Next, we move on to the Release stage. This flow looks something like the following:

The developer tags a branch for release, which triggers a build process for creating the artifact. This may have a QA process which then promotes the artifact to a development artifact repository. As you may have noticed, Workiva has a lot of compliance requirements since they deal with companies’ pre-financial data, so there is typically a sign-off process at various stages involving different parties like Release Management, QA, Security, etc. Depending on your compliance controls, this might just be clicking a button to promote an artifact to a production repository. From there, it can actually be deployed to a production environment.

With this workflow, artifact tagging, building, and promotion is all automated. It’s also important we have processes around security. Container and machine image auditing is automated as well as security patching for OS updates, etc. For example, this workflow might use something like Packer to automate AMI building. Finally, the artifact sign-off is streamlined for the various parties involved, if not fully automated.

Now we’re ready to actually deploy our application. This is a key part of self-service and “owning” a product. This allows a team to configure their application and, ideally, deploy it themselves to production. Initially, this might be handled by a Release Management team who actually clicks the deploy button, but as you become more confident in your processes and your tools become more mature, more of this responsibility can be pushed onto the development teams.

This is also where control comes into play. For instance, I may be allowed to configure my application to use 1GB of RAM, but if I need 1TB, I may need to get additional sign-off.

Self-service deploys and self-service configuration—with guard rails—are an important part of continuous deployment. Additionally, infrastructure provisioning should be automated. No more submitting tickets for a nameless Ops person to provision and configure servers, VMs, or other resources—no ticket-driven development.

I’ve been deliberate about not prescribing particular solutions for some of these problems. You might be using Kubernetes or ECS to orchestrate containers, it doesn’t really matter. These should mostly be implementation details. What does matter, though, is having good abstractions around certain implementation details. For example, Workiva was meticulous about building some layers around workload scheduling. This allowed them at one point to switch from using Fleet to ECS to manage containers with virtually no impact to developers. With the amount of churn that happens in tech, it’s important not to tie yourself too heavily to any one implementation. Instead, think about the APIs you expose for your infrastructure and consider those the deliverable.

Finally, we need to operate our service in production, another important part of ownership. There are a lot of products here, so we’ll just look at a cross section.

Logging is arguably the most important part of how we figure out what is happening in our systems. For this reason, Workiva built structured logging and metrics specs and language libraries implementing these specs. As a developer, this made it easy to simply pull in the library for your language and get structured, contextual logging for free. The other half to this was building out a data pipeline. Basically all metadata at Workiva went into Amazon Kinesis, including logs, metrics, and traces. First, this allowed us to reuse the same infrastructure for all of this data, from the agents running on the machines to the pipeline itself. Second, it allowed us to fan this data out to different backend systems—Splunk, SumoLogic, Datadog, Stackdriver, BigQuery, as well as various internal tools. This is probably one of the most important things you can do with your infrastructure.

Other continuous operations tools include telemetry, tracing, health checks, alerting, and more sophisticated production tools like canary deploys, A/B testing, and traffic shadowing. Some might refer to these as tools for testing in production. Realistically, once you reach a certain scale, testing in production is the only real alternative to the proliferation of deployment environments.

It’s worth mentioning that you do not need to build all of these products yourself. In fact, you shouldn’t. Many off-the-shelf solutions just need glued together. However, I’ve also come to realize that it’s often the “glue” that is important. That is to say, taking some large, commercial off-the-shelf solution and introducing it into a company is frequently rife with headaches. It’s like Jira, a big Frankenstein product that attempts to solve everyone’s problems and, in doing so, solves none of them particularly well. This is why I tend to favor small, modular solutions that can be composed. But it also highlights why there is a cultural aspect to this.

If you think the solution to your ailments is some magical product—maybe a CI/CD pipeline or Kubernetes or something else—you’re misguided. If anything, most problems are cultural, not technical in nature. Technology will not fix your broken culture! The products are not the endgame, they are a means to an end. And the products need to fit the company, its culture, its architecture, and its constraints. It’s tempting to take something you see on Hacker News and introduce it into your stack, but you have to be careful.

Likewise, it’s tempting to dive straight into the deep-end, automate everything, and build out a highly sophisticated infrastructure. But it’s important to start small and evolve over time. My approach to this is get the workflow correct, start manual, then automate more and more over time.

Wrapping Up

Specialization leads to misalignment and broken feedback loops, but it’s an important part of scaling a business. The question is: how do we specialize?

We know the traditional Ops model does not scale—devs will always out-demand capacity in this reactive model. Not only this, the siloing creates an empathy problem. DevOps attempts to help with this by tightening feedback loops and building empathy. NewOps takes this further by empowering teams and providing autonomy. It’s not a replacement for DevOps, it’s an evolution of it. It’s applying a product mindset to the traditional Ops model.

The future of Ops is taking Combined Engineering to its logical conclusion. As such, Ops teams should be redefining their vision from being masters of production to enablers of production. Just like with QA, Ops capabilities need to be embedded within dev teams, but the caveat is they need to be enabled! This is the direction Operations is headed. Software is eating the world, which means both up and down the stack. NewOps treats Ops like a product team whose product, effectively, is infrastructure. It’s creating guard rails, not walls—taking SDLC and compliance controls and encoding them into products rather than giving devs a laundry list of things, having them run the gauntlet through a long, drawn-out development process, and having a gatekeeper at the end.

Offloading responsibility helps correct and scale feedback loops. In my opinion, this is how we scale specialization. Operations isn’t going away, it’s just getting a product manager.

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The Future of Ops

Traditional Operations isn’t going away, it’s just retooling. The move from on-premise to cloud means Ops, in the classical sense, is largely being outsourced to cloud providers. This is the buzzword-compliant NoOps movement, of which many call the “successor” to DevOps, though that word has become pretty diluted these days. What this leaves is a thin but crucial slice between Amazon and the products built by development teams, encompassing infrastructure automation, deployment automation, configuration management, log management, and monitoring and instrumentation.

The future of Operations is actually, in many ways, much like the future of QA. Traditional QA roles are shifting away from test-focused to tools-focused. Engineers write code, unit tests, and integration tests. The tests run in CI and the code moves to production through a CD pipeline and canary rollouts. QA teams are shrinking, but what’s growing are the teams building the tools—the test frameworks, the CI environments, the CD pipelines. QA capabilities are now embedded within development teams. The SDET (Software Development Engineer in Test) model, popularized by companies like Microsoft and Amazon, was the first step in this direction. In 2014, Microsoft moved to a Combined Engineering model, merging SDET and SDE (Software Development Engineer) into one role, Software Engineer, who is responsible for product code, test code, and tools code.

The same is quickly becoming true for Ops. In my time with Workiva’s Infrastructure and Reliability group, we combined our Operations and Infrastructure Engineering teams into a single team effectively consisting of Site Reliability Engineers. This team is responsible for building and maintaining infrastructure services, configuration management, log management, container management, monitoring, etc.

I am a big proponent of leadership through vision. A compelling vision is what enables alignment between teams, minimizes the effects of functional and organizational silos, and intrinsically motivates and mobilizes people. It enables highly aligned and loosely coupled teams. It enables decision making. My vision for the future of Operations as an organizational competency is essentially taking Combined Engineering to its logical conclusion. Just as with QA, Ops capabilities should be embedded within development teams. The fact is, you can’t be an effective software engineer in a modern organization without Ops skills. Ops teams, as they exist today, should be redefining their vision.

The future of Ops is enabling developers to self-service through tooling, automation, and processes and empowering them to deploy and operate their services with minimal Ops intervention. Every role should be working towards automating itself out of a job.

If you asked an old-school Ops person to draw out the entire stack, from bare metal to customer, and circle what they care about, they would draw a circle around the entire thing. Then they would complain about the shitty products dev teams are shipping for which they get paged in the middle of the night. This is broadly an outdated and broken way of thinking that leads to the self-loathing, chainsmoking Ops stereotype. It’s a cop out and a bitterness resulting from a lack of empathy. If a service is throwing out-of-memory exceptions at 2AM, does it make sense to alert the Ops folks who have no insight or power to fix the problem? Or should we alert the developers who are intimately familiar with the system? The latter seems obvious, but the key is they need to be empowered to be notified of the situation, debug it, and resolve it autonomously.

The NewOps model instead should essentially treat Ops like a product team whose product is the infrastructure. Much like the way developers provide APIs for their services, Ops provide APIs for their infrastructure in the form of tools, UIs, automation, infrastructure as code, observability and alerting, etc.

In many ways, DevOps was about getting developers to empathize with Ops. NewOps is the opposite. Overly martyrlike and self-righteous Ops teams simply haven’t done enough to empower and offload responsibility onto dev teams. With this new Combined Engineering approach, we force developers to apply systems thinking in a holistic fashion. It’s often said: the only way engineers will build truly reliable systems is when they are directly accountable for them—meaning they are on call, not some other operator.

With this move, the old-school, wild-west-style of Operations needs to die. Ops is commonly the gatekeeper, and they view themselves as such. Old-school Ops is building in as much process as possible, slowing down development so that when they reach production, the developers have a near-perfectly reliable system. Old-school Ops then takes responsibility for operating that system once it’s run the gauntlet and reached production through painstaking effort.

Old-school Ops are often hypocrites. They advocate for rigorous SDLC and then bypass the same SDLC when it comes to maintaining infrastructure. NewOps means infrastructure is code. Config changes are code. Neither of which are exempt from the same SDLC to which developers must adhere. We codify change requests. We use immutable infrastructure and AMIs. We don’t push changes to a live environment without going through the process. Similarly, we need to encode compliance and other SDLC requirements which developers will not empathize with into tooling and process. Processes document and codify values.

Old-school Ops is constantly at odds with the Lean mentality. It’s purely interrupt-driven—putting out fires and fixing one problem after another. At the same time, it’s important to have balance. Will enabling dev teams to SSH into boxes or attach debuggers to containers in integration environments discourage them from properly instrumenting their applications? Will it promote pain displacement? It’s imperative to balance the Ops mentality with the Dev mentality.

Development teams often hold Ops responsible for being an innovation or delivery bottleneck. There needs to be empathy in both directions. It’s easy to vilify Ops but oftentimes they are just trying to keep up. You can innovate without having to adopt every bleeding-edge technology that hits Hacker News. On the other hand, modern Ops organizations need to realize they will almost never be able to meet the demand placed upon them. The sustainable approach—and the approach that instills empathy—is to break down the silos and share the responsibility. This is the future of Ops. With the move to cloud, Ops needs to reinvent itself by empowering and entrusting development teams, not trying to protect them from themselves.

Ops is dead, long live Ops!

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Take It to the Limit: Considerations for Building Reliable Systems

Complex systems usually operate in failure mode. This is because a complex system typically consists of many discrete pieces, each of which can fail in isolation (or in concert). In a microservice architecture where a given function potentially comprises several independent service calls, high availability hinges on the ability to be partially available. This is a core tenet behind resilience engineering. If a function depends on three services, each with a reliability of 90%, 95%, and 99%, respectively, partial availability could be the difference between 99.995% reliability and 84% reliability (assuming failures are independent). Resilience engineering means designing with failure as the normal.

Anticipating failure is the first step to resilience zen, but the second is embracing it. Telling the client “no” and failing on purpose is better than failing in unpredictable or unexpected ways. Backpressure is another critical resilience engineering pattern. Fundamentally, it’s about enforcing limits. This comes in the form of queue lengths, bandwidth throttling, traffic shaping, message rate limits, max payload sizes, etc. Prescribing these restrictions makes the limits explicit when they would otherwise be implicit (eventually your server will exhaust its memory, but since the limit is implicit, it’s unclear exactly when or what the consequences might be). Relying on unbounded queues and other implicit limits is like someone saying they know when to stop drinking because they eventually pass out.

Rate limiting is important not just to prevent bad actors from DoSing your system, but also yourself. Queue limits and message size limits are especially interesting because they seem to confuse and frustrate developers who haven’t fully internalized the motivation behind them. But really, these are just another form of rate limiting or, more generally, backpressure. Let’s look at max message size as a case study.

Imagine we have a system of distributed actors. An actor can send messages to other actors who, in turn, process the messages and may choose to send messages themselves. Now, as any good software engineer knows, the eighth fallacy of distributed computing is “the network is homogenous.” This means not all actors are using the same hardware, software, or network configuration. We have servers with 128GB RAM running Ubuntu, laptops with 16GB RAM running macOS, mobile clients with 2GB RAM running Android, IoT edge devices with 512MB RAM, and everything in between, all running a hodgepodge of software and network interfaces.

When we choose not to put an upper bound on message sizes, we are making an implicit assumption (recall the discussion on implicit/explicit limits from earlier). Put another way, you and everyone you interact with (likely unknowingly) enters an unspoken contract of which neither party can opt out. This is because any actor may send a message of arbitrary size. This means any downstream consumers of this message, either directly or indirectly, must also support arbitrarily large messages.

How can we test something that is arbitrary? We can’t. We have two options: either we make the limit explicit or we keep this implicit, arbitrarily binding contract. The former allows us to define our operating boundaries and gives us something to test. The latter requires us to test at some undefined production-level scale. The second option is literally gambling reliability for convenience. The limit is still there, it’s just hidden. When we don’t make it explicit, we make it easy to DoS ourselves in production. Limits become even more important when dealing with cloud infrastructure due to their multitenant nature. They prevent a bad actor (or yourself) from bringing down services or dominating infrastructure and system resources.

In our heterogeneous actor system, we have messages bound for mobile devices and web browsers, which are often single-threaded or memory-constrained consumers. Without an explicit limit on message size, a client could easily doom itself by requesting too much data or simply receiving data outside of its control—this is why the contract is unspoken but binding.

Let’s look at this from a different kind of engineering perspective. Consider another type of system: the US National Highway System. The US Department of Transportation uses the Federal Bridge Gross Weight Formula as a means to prevent heavy vehicles from damaging roads and bridges. It’s really the same engineering problem, just a different discipline and a different type of infrastructure.

The August 2007 collapse of the Interstate 35W Mississippi River bridge in Minneapolis brought renewed attention to the issue of truck weights and their relation to bridge stress. In November 2008, the National Transportation Safety Board determined there had been several reasons for the bridge’s collapse, including (but not limited to): faulty gusset plates, inadequate inspections, and the extra weight of heavy construction equipment combined with the weight of rush hour traffic.

The DOT relies on weigh stations to ensure trucks comply with federal weight regulations, fining those that exceed restrictions without an overweight permit.

The federal maximum weight is set at 80,000 pounds. Trucks exceeding the federal weight limit can still operate on the country’s highways with an overweight permit, but such permits are only issued before the scheduled trip and expire at the end of the trip. Overweight permits are only issued for loads that cannot be broken down to smaller shipments that fall below the federal weight limit, and if there is no other alternative to moving the cargo by truck.

Weight limits need to be enforced so civil engineers have a defined operating range for the roads, bridges, and other infrastructure they build. Computers are no different. This is the reason many systems enforce these types of limits. For example, Amazon clearly publishes the limits for its Simple Queue Service—the max in-flight messages for standard queues is 120,000 messages and 20,000 messages for FIFO queues. Messages are limited to 256KB in size. Amazon Kinesis, Apache Kafka, NATS, and Google App Engine pull queues all limit messages to 1MB in size. These limits allow the system designers to optimize their infrastructure and ameliorate some of the risks of multitenancy—not to mention it makes capacity planning much easier.

Unbounded anything—whether its queues, message sizes, queries, or traffic—is a resilience engineering anti-pattern. Without explicit limits, things fail in unexpected and unpredictable ways. Remember, the limits exist, they’re just hidden. By making them explicit, we restrict the failure domain giving us more predictability, longer mean time between failures, and shorter mean time to recovery at the cost of more upfront work or slightly more complexity.

It’s better to be explicit and handle these limits upfront than to punt on the problem and allow systems to fail in unexpected ways. The latter might seem like less work at first but will lead to more problems long term. By requiring developers to deal with these limitations directly, they will think through their APIs and business logic more thoroughly and design better interactions with respect to stability, scalability, and performance.

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Designed to Fail

When it comes to reliability engineering, people often talk about things like fault injection, monitoring, and operations runbooks. These are all critical pieces for building systems which can withstand failure, but what’s less talked about is the need to design systems which deliberately fail.

Reliability design has a natural progression which closely follows that of architectural design. With monolithic systems, we care more about preventing failure from occurring. With service-oriented architectures, controlling failure becomes less manageable, so instead we learn to anticipate it. With highly distributed microservice architectures where failure is all but guaranteed, we embrace it.

What does it mean to embrace failure? Anticipating failure is understanding the behavior when things go wrong, building systems to be resilient to it, and having a game plan for when it happens, either manual or automated. Embracing failure means making a conscious decision to purposely fail, and it’s essential for building highly available large-scale systems.

A microservice architecture typically means a complex web of service dependencies. One of SOA’s goals is to isolate failure and allow for graceful degradation. The key to being highly available is learning to be partially available. Frequently, one of the requirements for partial availability is telling the client “no.” Outright rejecting service requests is often better than allowing them to back up because, when dealing with distributed services, the latter usually results in cascading failure across dependent systems.

While designing our distributed messaging service at Workiva, we made explicit decisions to drop messages on the floor if we detect the system is becoming overloaded. As queues become backed up, incoming messages are discarded, a statsd counter is incremented, and a backpressure notification is sent to the client. Upon receiving this notification, the client can respond accordingly by failing fast, exponentially backing off, or using some other flow-control strategy. By bounding resource utilization, we maintain predictable performance, predictable (and measurable) lossiness, and impede cascading failure.

Other techniques include building kill switches into service calls and routers. If an overloaded service is not essential to core business, we fail fast on calls to it to prevent availability or latency problems upstream. For example, a spam-detection service is not essential to an email system, so if it’s unavailable or overwhelmed, we can simply bypass it. Netflix’s Hystrix has a set of really nice patterns for handling this.

If we’re not careful, we can often be our own worst enemy. Many times, it’s our own internal services which cause the biggest DoS attacks on ourselves. By isolating and controlling it, we can prevent failure from becoming widespread and unpredictable. By building in backpressure mechanisms and other types of intentional “failure” modes, we can ensure better availability and reliability for our systems through graceful degradation. Sometimes it’s better to fight fire with fire and failure with failure.