Hacker News new | ask | show | jobs
by shric 1465 days ago
An SLA of 100% simply means you agree to compensate your customers (as specified, usually with credit) if your service is down at all, nothing more.

Also, SRE here but not for Cloudflare -- I've never seen SREs directly involved in externally published SLAs, they usually come from legal. We deal with SLOs on more fine grained SLIs than overall uptime
1 comments
codethief 1465 days ago
> SLA […] SRE […] SLOs […] SLIs

I made it to SLA (which I believe stands for service level agreement). What do the other abbreviations stand for?

link
shric 1465 days ago
SRE - Site Reliability Engineer (a term Google came up with that's been adopted elsewhere) Google defined it approximately as what happens when you apply software engineering practices to what was traditionally an operations function.

SLO - Service Level Objective - the service level you strive for. If it's higher you have room for experimentation, etc.

SLI - Service Level Indicator - the actual metric(s) you use to measure a service level (latency, error rate, throughput, etc.)

link
nsheridan 1465 days ago
SLA - correct. That’s the contract between the operator and the users which describes the penalties for not meeting agreed-upon SLO

SLO - service level objective, the stated availability (or latency or durability etc) of the service. Usually expressed as a value over a period of time (e.g 99.9% availability as measured over a moving 30 average). The SLO is measured by the SLI.

SLI - service level indicator. Simply, the direct measurement of the service (i.e metrics)

SRE - Site Reliability Engineer, usually a member of a team who is responsible for the continued availability of the service and the poor sap who gets paged when it breaches SLO or has an outage or other impactful event.

link
KarlKode 1465 days ago
SRE: Site reliability engineer

SLI: Service level indicator (Metric to measure the health of a service. For example successful requests per interval / total requests per interval.)

SLO: Service level objective (what performance you expect eg. the previously mentioned SLI is >= 99.5%)

SLA: Servicelevel agreement (legal agreement that defines what happens if a SLO is not met)

link