Why Your Cloud Server Shows 'Running' But Still Refuses Connections

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A cloud instance showing a 'Running' status does not mean it is reachable — the two states are entirely separate. Successful connectivity depends on five correctly configured networking components: a Virtual Cloud Network (VCN), subnets, route tables, internet gateways, and security lists. Using a house-and-property analogy, the guide explains that a VCN acts as the foundational fenced land on which all other infrastructure must be built, not the other way around. Missing even one of the five components results in connection timeouts, even when the server itself is fully operational. Most cloud providers, including Oracle, auto-generate default versions of these components, but misconfigurations remain a common source of connectivity failures.

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