What is an SLA?
A Service Level Agreement (SLA) is a formal commitment between a service provider and customer that defines the expected level of service. It specifies metrics, responsibilities, and consequences for not meeting the agreed standards.
SLA Components
Service Description What services are covered.
Performance Metrics
- Availability (uptime)
- Response time
- Throughput
- Error rates
Responsibilities
- Provider obligations
- Customer obligations
Remedies
- Credits for failures
- Escalation procedures
- Termination rights
Common Metrics
| Metric | Definition |
|---|---|
| Availability | Uptime percentage |
| MTTR | Mean time to repair |
| MTBF | Mean time between failures |
| Response Time | Time to first response |
| Resolution Time | Time to fix issue |
Availability Levels
| Level | Downtime/Year |
|---|---|
| 99% | 3.65 days |
| 99.9% | 8.76 hours |
| 99.99% | 52.56 minutes |
| 99.999% | 5.26 minutes |
SLA vs SLO vs SLI
SLA External commitment with consequences.
SLO (Service Level Objective) Internal target.
SLI (Service Level Indicator) Actual metric measurement.
Best Practices
- Define measurable metrics
- Align with business needs
- Include exclusions
- Regular review
- Clear reporting
- Realistic targets