Stage 1 · Lesson 3 of 6
Setting SLOs and SLAs
An (service level objective) is a target for an over a rolling window, such as 99.9 per cent of checkout requests succeed over 30 days. It is internal: the team and product owners agree it and plan work around it. An (service level agreement) is an external contract with customers, usually with service credits if it is missed.
The SLO should be stricter than the SLA so you react before money is owed. Start from current performance and user expectations, not from a round number you like, then revise after a few months. Different user journeys can deserve different SLOs: browsing may tolerate more failure than payment.
Common trapcopying a target such as 99.99 per cent from another company without checking whether your dependencies can even support it.
A question to check yourself, an AI practice session and 2 cheat sheet entries come with the full roadmap. Unlock
Resources for this stage
Start with· follow one of these
- BookFreeGoogle Site Reliability Engineering Book
Google · Advanced
Free online: read the chapters on embracing risk and service level objectives first
- BookFreeThe Site Reliability Workbook
Google (O'Reilly) · Intermediate
Free online: the Implementing SLOs chapter walks through a worked example and an error budget policy