Service Level Objectives with Reliably

Service Level Objectives are a core element of your reliability effort.

Service Level Objectives identify what you should care about on your system. They are what good looks like for the users of your system. If an SLO is underperforming, it will be impacting your users in some way. They're a signal of your services health, allowing you to make decisions about what you should focus on next.

Discover how the Reliably CLI allows to define and measure SLOs.

What are SLOs again?

SLOs are one of the three Service Level concepts that power the SRE practice, alongside Service Level Indicators and Service Level Agreements.

tip

If you want to read more about SRE terminology, the Google Cloud Blog article SRE fundamentals: SLIs, SLAs and SLOs is a good starting point.

SLOs with Reliably

The Reliably CLI allows you to define SLOs for Availability and Latency.

An Availability SLO allows you to specify a target availability percentage for a Service.

A Latency SLO allows you to specify a threshold latency for a service and a target percentage. The percentage gives the target percentage of responses within that threshold latency.

Service Level Indicator

An SLI is a measurement of your service's behaviour.

Error rate, latency, etc. are SLIs.

Note

When you use the Reliably CLI you can measure the performance of your SLOs by including SLIs in your Reliably manifests. Currently you can measure Availability and Latency SLOs with AWS or GCP resources.

Define Service Level Objectives

Service Level Objective

With SLIs in mind, an SLO is a target for your SLIs.

Example SLOs:

  • 99% of successful requests on a service
  • 98% of requests on a service fulfilled in less than 100 ms

Service Level Agreements

Service Level Agreements are contracts with the client and so represent the minimum that can be provided, below which the customer will be more than unhappy.

Managing your SLOs with the Reliably CLI

The Reliably CLI provides the slo init and slo report commands to allow you to define and report on your SLOs.

Define your SLOs in the terminal with the Reliably CLI.

Generate actionable reports.

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