Two eras of infrastructure management with fundamentally different assumptions about change. ## Technology Shift (Table 1-1) | Dimension | Iron Age | Cloud Age | |-----------|----------|-----------| | Resources | Physical hardware | Virtualized resources | | Provisioning | Days or weeks | Minutes or seconds | | Process | Manual (runbooks) | Automated (code) | ## Mindset Shift (Table 1-2) | Dimension | Iron Age | Cloud Age | |-----------|----------|-----------| | Cost of change | High | Low | | Changes are | Risks to minimize | Essential to improve quality | | A change of plan means | Failure of planning | Success in learning | | Optimize to | Reduce opportunities to fail | Maximize speed of improvement | | Delivery approach | Large batches, test at the end | Small changes, test continually | | Architecture | Monolithic (fewer, larger parts) | Microservices (more, smaller parts) | ## The Implication The Iron Age approach to risk is self-defeating: adding barriers to change impedes the fixing and improvement that would reduce risk. Cloud Age methodology (Lean, Agile, DevOps) treats frequent, small changes as the mechanism *for* achieving reliability — not a threat to it. --- *Source: [[Infrastructure as Code, 3rd Edition — Kief Morris]] (Kief Morris, O'Reilly 2025) — Ch 1 — What Is Infrastructure as Code?*