1Z0-1072-25: Oracle Cloud Infrastructure 2025 Architect Associate

By Oracle · Question Mode

QuestionQ31

VerifiedNetworking

A newly hired network administrator is tasked with removing SSH permissions from every compute instance in the company’s tenancy. She uses Tenancy Explorer to locate all Virtual Cloud Networks (VCNs) in the tenancy.

She removes port 22 from the Security Lists in every VCN. After finishing the task, she tests SSH access to the first compute instance and finds that she can still SSH to it.

Why is this occurring?

Explanation

In OCI, the effective security rules for a VNIC are the union of the security-list rules associated with its subnet and the rules in every Network Security Group (NSG) assigned to that VNIC. A stateful NSG ingress rule allowing all protocols from 0.0.0.0/0 includes TCP port 22, so SSH remains permitted even after port 22 is removed from the VCN security lists.

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