advancedScenario-Based & System Design Questions

A container can `ping` another container by IP but DNS resolution by container name fails.

This is the classic default-bridge-network trap: the default bridge network does not provide embedded DNS, only IP-level connectivity. Fix by creating and using a user-defined bridge network (or, in Compose, simply relying on its auto-created project network) — both provide automatic name-based service discovery that the default bridge lacks.

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