The term Site Reliability Engineering (SRE) owes its origins to Google's approach of leveraging automation, tools, and processes in Operations and Service Management. The objective was to ensure service reliability and availability within operations management. At its core, Site Reliability Engineering is the practice of applying software engineering skills to IT operations, that maximizes reliability and efficiency of software systems while improving workflow.
The older approach to Service Management involved System Administrators to maintain services while managing critical events and updates as per their priority. This had a significant drawback as the approach required regular manual interventions proving cost-intensive.
Site Reliability Engineering addressed such drawbacks by introducing professionals called Site Reliability Engineers. These individuals are responsible for building and integrating software tools to improve organizational systems' reliability, automation, and scalability. Over time, as the field evolved, it included solutions like on-call monitoring, automated capacity planning, infrastructure scaling, and plans for disaster recovery.
In the sections to follow, we will address in detail their responsibilities, how SRE differs from DevOps, and things to keep in mind when considering this career path.
Site Reliability Engineer Roles and Responsibilities
Automation of IT Operations
Handling IT operations involves performing the same functions day in, day out. Instead of manually performing these functions, SRE emphasizes the need to automate them. As part of their core responsibilities, SRE Engineers build tools that aid automation in managing IT operations and support. As such, Site Reliability Engineers enable automation for some of the following key functions -
- Continuous Integration and Delivery (CI/CD) across SDLC phases
- Incident Response
- Infrastructure Component Provisioning
Site Reliability Engineers are responsible for ensuring that services are available, the underlying infrastructure is properly functioning, and other internal tools, processes, and systems are working as expected. An essential responsibility also includes monitoring critical applications and related services to ensure availability during critical business hours.
Specifying Service Level Indicators and Objectives
Service Level Objectives are defined levels of service uptime or availability that act as essential metric indicators for measuring performance.
SRE Engineers are responsible for identifying and creating indicators, while keeping an eye on performance. This involves analyzing historical data and setting realistic objectives to meet Service Level Agreements (SLAs).
Incident Management and Disaster Recovery
Possibly one of the most crucial responsibilities of an SRE Engineer is to collaborate for high-priority Incident Tickets and ensuring system recovery within an SLA. When an outage occurs, the first step to recovery is to utilize monitoring systems and diagnose the root cause. Armed with this information, site reliability engineers can proceed to manage the incident properly and restore the system online.
On-Call Support and Issue Resolution
Overlapping the role above, SRE engineers have to be on stand-by to interface with developers when issues arise and get escalated. They interact with developers to provide consultation and troubleshooting services when alerts get raised.
When a developer escalates an issue, the Site Reliability Engineer investigates, diagnoses the problem, and subsequently resolves it. An SRE engineer may also include other engineers if required. Besides, SRE engineers ensure high-priority tickets are handled for a speedy resolution to meet Service Level Agreement.
Facilitate Post Incident Analysis
Following an incident’s resolution, there is the need to revisit the events that occurred and determine the root cause. A Site Reliability Engineer is involved in this review process and is responsible for identifying the root-cause and how to prevent the future occurrence of similar incidents.
As SRE engineers have access to both staging and production environments, they gather a wealth of knowledge about the system over time. It is expected that they document this information to make it available for other engineers and teams when they need it.
They are also expected to keep records of outages of the system. These records provide critical insights about long-term trends while assisting the organization to produce reasonable Service Level Agreements. More so, keeping records of incidents, especially low priority ones, is specifically useful in identifying and resolving elusive bugs within the system.
The Difference Between SRE and DevOps
DevOps is a combination of tools and practices designed to automate and integrate processes between the development and operations team to make software production and deployment reliable. There is a tendency to assume that SRE and DevOps refer to the same thing. However, there are some notable differences highlighted below:
- Success Score: DevOps measures successful implementation by focusing on metrics to measure the automation of deployments and the frequency of failure or error occurrence. While SRE relies on DevOps processes to measure successful implementation in terms of reliability of the system and uses reliability metrics like Service Level Objectives to continually improve the system
- Automation: Although they both leverage automation for repetitive tasks, DevOps uses automation to increase developer efficiency and improve the release quality, while automation in SRE aims to reduce the cost of error.
- Processes: The processes that are automated are also different. In DevOps, tasks such as deployments, application restarts, and backups are primarily of the focus. SRE automates these functions, as well as processes concerned with modifying the architecture and implementing new technologies.
- Operations: DevOps is concerned with continuous delivery up to the point of deployment, while SRE is concerned with providing ongoing operations support at the end of consumer consumption.
- Development: DevOps focuses on getting through the development pipeline more efficiently when it comes to code or new features. SRE is more concerned with balancing site reliability with the addition of new features.
- Fault Tolerance: When it comes to failure management, DevOps finds a way to tolerate failure instead of spending time making the system fully fault-tolerant. SRE, on the other hand, determines how much failure is acceptable as defined in the error budget. SRE focuses on identifying failures and evaluating them to prevent them from happening the same way again.
Site Reliability Engineer Role - Pros and Cons
Pros of the SRE Role
- As Site Reliability Engineers focus on system reliability, they reduce operational expenses, lessen and mitigate failure points, while automating monotonous time and resource wasting tasks. The organization thus gains economic savings both in terms of effort and money.
- Increased system accuracy and efficiency as a result of wider automation administered by Site Reliability Engineers.
- Failure resolution is preemptive as SRE Engineers identify failure causes early while mitigating faults more holistically.
Cons of the SRE Role
- Because of the relatively recent adoption of reliability engineering, most site reliability engineers deal with uncharted territory. Therefore, it can be difficult to fix any potential crack with its adoption.
- The bar of entry is high as it requires having a wide array of skill sets from operations management, coding, and testing.
Factors to Consider When Choosing SRE as a Career
If you are considering choosing SRE as a career, here are a few things you should keep in mind:
- A Site Reliability Engineer must have a software-centric mindset.
- The primary focus of Site Reliability Engineering is system reliability and performance. An SRE Engineer must understand that improving reliability and performance is done by keeping software at the center of the process.
- Programming is requisite for a Site Reliability Engineering role because of the need to automate its functions. As a result, it is expected that you must be comfortable with coding in a variety of programming languages and vary from company to company.
- A Site Reliability Engineer job description requires a passion for automating things. If you find yourself automating mundane development tasks, then you are on the right track.
Site Reliability Engineering is a paradigm within a software lifecycle, that handles operations using software principles to create reliable systems.
Typically, Site Reliability Engineers are responsible for both technical and operational tasks in the organization. As part of their essential duties, SRE Engineers use their engineering skills to automate and lessen the need for manual intervention in operations management. Besides, they are also responsible for Monitoring, Issue Resolutions, Disaster Recovery, and Internal Tooling and Processes of an organization.
A site reliability role is usually challenging that requires commitment and a passion for automation, coding skills, and a software-centric mindset. The roles and responsibilities these professionals play in an organization help reduce operational costs while improving the reliability of the system, thus, benefitting both customers and the organization.