SLI, SLO and SLA

What are SLIs, SLOs and SLAs? 

Service Level Indicators (SLIs) are metrics that you choose to measure the health and performance of your services. Service Level Objectives (SLOs) are the desired target for those indicators. Service Level Agreements (SLAs) build on this and include the consequences of not meeting those targets. All are fundamental to Site Reliability Engineering.

In this post, I’ll try to explain each in more detail, how they relate to each other, and some examples of each.

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Tags: seekingsrebook, servicelevelagreements, sitereliabilityengineering, sla, SLAs, sli, SLIs, slo, SLOs, sre, thesrebook

Post Production Debugging

Monitoring and Observing Your App Post Release

Pre-release tests are essential, but the ability to debug, monitor and observe your application suite post-release is what allows you to detect, and quickly fix, the production problems that will inevitably rise.

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Tags: apdex, KPIs, monitoring, mttd, mttf, mttr, o11y, observability, production, SLAs, testinginproduction

AWS S3 SLAs

According to the AWS S3 docs, S3 is designed for 99.99% availability over a given year, but their SLA compensates you when availability drops below 99.9% monthly uptime. That is, you will receive some level of refund (up to 25%) if there is more than 43 minutes of downtime per month.

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Tags: aws, s3, servicelevelagreements, SLAs