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Composite SLA & System Reliability Calculator
Model composite system availability, annual downtime windows, and composite MTTR/MTBF for serial and redundant systems.
Inputs
Gateway / CDN Layer
API Application Service
Database Storage Tier
MTBF / MTTR Auditor
Results
Composite Availability SLA
99.8401%
Formula
Composite SLA formula
Uptime = Gateway × [ 1 - (1 - API_SLA)^N ] × [ 1 - (1 - DB_SLA)^M ]Multiplies serial components together, while parallel redundant arrays increase individual segment uptime.
Step by step
How the calculation works
- 1Define the SLA percentages for Gateway, API services, and Database layers.
- 2Choose the redundancy level (parallel instances) for the API and Database tiers.
- 3Input your estimated Mean Time Between Failures (MTBF) and Mean Time To Repair (MTTR) to cross-check reliability.
- 4Review composite SLA, annual downtime windows, and verify uptime requirements.
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