Start an Istio pilot with a concrete need, such as service-to-service authorization, traffic shifting, or telemetry. Apply it to a small staging service pair and test allowed and denied requests, a rollout split, and what happens when a proxy or control-plane component fails.
A service mesh adds configuration and operational dependencies. Measure latency and resource overhead, and make sure developers can debug routing and policy decisions. If a simpler ingress or application-level solution meets the need, the extra layer may not be worth operating.
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