Availability metrics
Uptime = the percentage of time the system is up. Downtime = when it is unavailable. 99.9% ≈ 8.7 hours of downtime per month. 99.99% ≈ 52 minutes of downtime per month.
Reducing downtime
Highly available architecture: remove single points of failure. Proactive monitoring: surface issues early. Fast recovery: standardized recovery flows. Key advantages: full-stack visibility from hardware to application, predictive maintenance, fast fault location, automated recovery.