Fundamentals of DevOps

The DevOps shift constitutes a two-pronged approach to ecosystem management—one constantly adherent to best practices and tight collaboration. Teams that embrace the fundamentals of DevOps excel at working efficiently, and have a deeper understanding of infrastructure performance vs. baseline expectations.

This chapter dives into practices that are absolutely pivotal to DevOps success. Follow along as we analyze both the fundamentals of DevOps and why they're so indispensable.

Continuous Integration

As the moniker implies, continuous integration (CI) is the ongoing process of streamlining software development internally. Coding projects are commonly separated into manageable chunks in a DevOps environment. It's up to developers and teams alike to take the features they "own" and commit them to a shared codebase. That's the type of integration we're after. Accordingly, the piecemeal nature of these applications allows for frequent updates—often multiple times daily.

However, developers can't just push build updates haphazardly. CI is tightly controlled; new commits trigger the creation of fresh test builds via your build-management system. Redundant code is rejected, and breaking changes are minimized once master branches are altered. Incremental changes are encouraged. Additionally, reduced reconciliation prevents mandatory code freezes that commonly stem from conflicts.

Overall, continuous integration slashes issue mitigation time, boosts multi-contributor merge confidence, and helps shorten the development pipeline.

Continuous Delivery

While CI focuses on internal code contributions, continuous delivery (CD) brings software closer to completion by automatically delivering completed code blocks to the master. After an application component is deemed ready to go, it's CD's job to seamlessly merge it into the overarching package—like plugging multiple appliances into a power strip without causing a short.

Continuous delivery (CD) is often confused with continuous deployment—the next process in line, which brings finalized code into production. Deployment is the act of making applications and updates available to end users. Accordingly, the CD acronym is known primarily as "continuous delivery" or "continuous delivery and deployment," but rarely continuous deployment.

CD takes code and adds it to a repository, like GitHub or a container registry (in microservices environments). The end goal is to increase release consistency while providing a server-side testbed for impactful features. Update processes become nimbler as a result.

Continuous Testing and Validation

Tying directly into CI/CD, testing processes are integral to delivering functional software to customers. There's now a major emphasis on shift-left testing—which inserts such procedures as soon as possible within the DevOps pipeline. Testing early and often is key to catching nasty bugs before they impact release software.

Not convinced? Consider that critical production bugs cost four-to-five times more to fix than pre-release issues—upwards of $10,000 in some cases. Companies have caught on, hence why most earmark 10 to 49% of their QA budgets for testing automation.

Continuous testing is key to CI, as builds otherwise wouldn't pass their checks. Teams use automated scripts to inspect code, highlight issues, and send offending blocks back to developers. DevOps-style testing seeks to eliminate bottlenecks. Virtualization also saves massive time over manually moving each commit. Another crucial outcome of testing and validation is better software quality in alignment with client SLOs. Metrics like uptime, performance, and more depend on sound QA.

Continuous Monitoring and Observability

Though we like to believe our CI/CD processes are airtight, there are often opportunities for improvement. Monitoring and observability (M&O) are key to understanding how each segment fits together, who owns what, and how efficiency may improve. Detecting issues and vulnerabilities is always important. Teams can handle this internally or employ third-party tools for greater ease.

Monitoring is no longer done solely on the ops side. Many stakeholders (developers, testers, QA, and engineers of multiple disciplines) play crucial roles throughout the software development lifecycle. Understanding CI/CD events and associated alerts will help technical parties solve problems—like failures and bottlenecks. Continual data capture can be empowering when leveraged intelligently.

This is also where DevOps culture comes into play. Every impactful problem has an objective, post-mortem assessment which dissects why it arose. The blameless foundation of M&O allows teams to tackle challenges without fear of repercussions. Better systems and resources responsively arise to prevent history from repeating itself.

Continuous Security

Another fundamental of DevOps is strong security—based on testing, tooling, authorization, and inventory tracking. Regular out-of-band penetration testing is essential to keeping your infrastructure hardened against attack. While many vulnerabilities are invisible, this type of testing can leverage remote servers to uncover them. This is on top of regular code validation and testing, to keep bugs at bay. Overall, continuous security uses integrated tools to enable this.

Generally, it's also best to keep source code under lock and key. Good security means good privilege delegation, and not all teams or developers should enjoy equal levels of access. This code is proprietary and often contains some company IP.

Software composition analysis also plays a security role. Keeping record of all software packages and versioning via infrastructure as code is important. Running automated CVE detection across these components and remediation strategies can boost security over time. Any continuous security measures implemented should be automated as appropriate, as not to hamper efficiency. Any measures should happen ASAP within the development lifecycle.

Cross-Team Collaboration

Finally, busting down silos is paramount for ensuring good communication and unification across the DevOps pipeline. Effective DevOps execution means establishing a single source of truth—aggregating data from many sources into one collective location. Testers, engineers, QA, and even non-technical stakeholders can gain valuable insights from these bits of information.

Seamless cooperation between developers and ops teams is especially critical. DevOps processes coexist in a continuous cycle; this is called a feedback loop. Different portions of a project are completed and reviewed by stakeholders, and feedback from those steps is returned. Code must be written, tested, validated, delivered, built, and ultimately deployed for end users.

Cross-team collaboration benefits from accelerating this cycle. Accordingly, automation has become a key ingredient in shortening it from end to end—chiefly by reducing friction caused by having too many cooks in the kitchen (when they're not needed).