Within the realm of software development, two related ideas known as “DevOps” and “Site Reliability Engineering” (SRE) have been coexisting for more than a decade now. It’s possible that they could be considered rival businesses at first glance. However, a closer look reveals that the apparent competitors are, in reality, pieces of a puzzle that complement and fit together nicely.
This article explains how DevOps and SRE make it easier to develop reliable software, where the two practices overlap, how they are distinct, and when they can most effectively work together.
A Comparison between SRE and DevOps
Two distinct methodologies aim to achieve the same result: to close the gap between the development and operations teams. Both initiatives seek to shorten the release cycle and enhance the product’s reliability. But before we delve any further into the distinctions and parallels that exist between the two, let’s take a step back and consider when and why SRE and DevOps came into existence in the first place.
Site Reliability Engineering, also known as SRE, is an innovative method of approaching information technology operations that puts software first and is supported by a set of corresponding practices. It was developed at Google in the early 2000s to monitor the overall health of a large and complex system that handled more than 100 billion requests daily.
The elements that contribute to the reliability are presented in the form of a pyramid below. The elements range from the most fundamental (monitoring) to the most sophisticated (reliable product launches).
What is meant by DevOps?
In 2009, Belgian information technology consultant and Agile practitioner Patrick Debois came up with the term “DevOps,” which is an abbreviation for “development and operations.” Applying engineering practices to operational tasks, measuring the results of one’s efforts, and relying on automation rather than manual labor are some of its core principles comparable to those of SRE. However, a much broader scope is covered by it.
DevOps services aim to cover the entire product life cycle, from design to operations, and make all processes continuous after Agile methodologies. In contrast, SRE focuses on keeping services running and making them available to users. Maintaining such continuity from beginning to end is necessary to cut down on time to market and adapt quickly—the lifecycle of DevOps.
Five key DevOps Pillars
No more silos
The concept originates from the observation that the output level produced by a group of people is directly proportional to the degree to which they collaborate and share information.
Failures are normal
Instead of wasting resources trying to achieve an unreachable goal like eliminating all failures, the DevOps methodology encourages learning from previous errors.
They are the safest and most effective when changes are made frequently and in small amounts. The concepts of continuous integration and continuous delivery, abbreviated as CI/CD, have their foundations in this pillar, which, combined with automated testing of small batches of code and rollback of problematic batches.
The goal of automating DevOps processes is to speed up the delivery of software updates and reduce the amount of time spent on manual labor.
Metrics are crucial
Each modification needs to be evaluated using metrics to determine whether or not it has the desired effect.
What SRE has to Offer in Terms of Putting these Pillars into Action
Here is a brief outline of the importance of SRE in deriving optimal value from a DevOps initiative:
Consider the operation of the system a software issue
In a nutshell, software solutions are developed to teach a computer how to carry out tasks associated with information technology in an automated manner without the need for intervention from a human.
Track the system’s availability and uptime using the metrics provided
According to SRE, one of the most important prerequisites for the success of a system is its availability. Your service will be unable to carry out its necessary operations if it is unavailable during a specific period. SRE provides three metrics to measure availability.
Quantitative measurement of the behavior of a system.
The Service-Level Objective, also known as SLO.
A Service-Level Agreement, or SLA, promises customers that their service will meet certain Service-Level Objectives (SLOs).
Set error budget
This phrase is the counterpart to “failure is normal,” “the pace of change ought to be moderate,” and “metrics are crucial.”
Because it is impossible to achieve, the goal of achieving 100 percent reliability is not pursued by SRE. In addition, once a predetermined level is reached, further improvements in the system’s reliability are no longer advantageous, slows down the rate of updates, and reduce their frequency.
Therefore, the objective of SRE is to provide sufficiently good services without compromising the ability to provide frequently updated features promptly. This strategy allows for the presence of an acceptable risk of failure, which is referred to as the error budget.
The error budget at Google is defined every quarter concerning SLOs. This provides a clear picture of the amount of risk that can be taken within a quarter.
Lessen the financial impact of mistakes
This phrase is the counterpart to “failure is normal” and “the pace of change ought to be slow and steady.”
The higher the cost of repairing an error, the later in the product’s life cycle it is discovered that an error exists. SRE is aware of this fact and tries to resolve issues at the earliest possible stage by utilizing the practices listed below.
1. Always make early and frequent rollbacks.
When an error is found or even suspected to be present in a release, the team will roll back the release first and investigate the issue. This strategy shortens the Mean Time to Recovery (MTTR), which refers to the typical amount of time required to bring your service back online after it has failed.
2. Canary every rollout
The canary release method can make the rollout procedure more secure. First, a beta version of the update is distributed to a select group of users. They put it through some testing and give their feedback. Once the release has been updated with the necessary changes, it is made available to everyone. Canary releases shorten the Mean Time to Detect, also known as MTTD, which is the amount of time it typically takes for your team to identify an issue. Additionally, this method impacts fewer customers when there is a system malfunction.
Playbooks should be created and maintained.
This concept corresponds to phrases such as “no more silos” and “automate everything.”
Playbooks, also known as playbooks, are documents that describe diagnostic procedures and ways to react to automated alerts. Playbooks are also sometimes referred to as playbooks. Meantime to Repair (MTTR), stress, and the risk of human error are all reduced due to their use.
The information contained in playbooks becomes obsolete when there is a shift in the environment. Therefore, in the case of daily releases, these guides must be updated daily as well; considering how challenging it is to produce high-quality documentation, some SREs advocate for creating only general instructions that are updated infrequently. Some people are adamant about having comprehensive playbooks that outline each step in detail.
When Is It Necessary For Businesses To Have Both DevOps And SRE
Despite all the ambiguity and overlaps, one thing can be said with a high degree of certainty: SRE and DevOps are not competing factions; rather, they are two relatives working towards the same goal and utilizing the same tools, but with slightly different concentrations.
Whereas the SRE culture emphasizes dependability rather than the speed of change, the DevOps culture emphasizes agility throughout the entire product development cycle. Despite this, both strategies aim to strike a middle ground between two extremes and can complement one another regarding their methods, practices, and solutions.
No matter how big your company is, someone is probably working there who fills the role of a Site Reliability Engineer (SRE), fosters collaboration between software developers and information technology specialists, or composes scripts to automate labor-intensive processes. If you can track these individuals down and formally acknowledge the work that they have done, then you will have the foundation for an efficient SRE or DevOps team, depending on which name you prefer. We trust that this article will prove informative. Until next time, happy developing!