Core Oci Services practice questions

Lower Cost

Why it fails: Lower Cost is optimized for large sequential workloads or infrequent access storage.

Basic

Why it fails: Basic is designed for boot volumes and non-performance-critical workloads.

Balanced

Why it fails: Balanced is used for general-purpose workloads with moderate IOPS requirements.

HTTP request rate and database query latency

Why it fails: These require custom alarms and notifications rather than native instance pool autoscaling configuration.

Disk I/O throughput and Network packet drops

Why it fails: These are not default native autoscaling metric triggers.

GPU temperature and power consumption

Why it fails: These are hardware metrics not used for instance pool autoscaling.

Local Peering Gateway

Why it fails: Local Peering Gateway is for VCN-to-VCN peering within a region.

Object Storage Shapes

Why it fails: Object Storage is a storage service, not a compute shape.

Database Shapes

Why it fails: Database shapes are specific to Oracle Database deployments.

Network Shapes

Why it fails: Networking services do not use compute shapes.

Internet Gateway with NAT

Why it fails: Internet gateways route public traffic.

Remote Peering Connection via DRG

Why it fails: Remote Peering Connection is for VCNs in different regions.

Change the VCN route table during maintenance windows

Why it fails: Route tables do not affect host infrastructure maintenance.

Attach an additional Block Volume to prevent host reboots

Why it fails: Block volumes do not prevent host maintenance reboots.

Convert the virtual machine into a Bare Metal server

Why it fails: VMs cannot be converted to bare metal in-place.

Dynamic Routing Gateway policies

Why it fails: DRG routes inter-network traffic.

Internet Gateway rules

Why it fails: Internet Gateway routes internet traffic.

Security Lists

Why it fails: Security lists apply to entire subnets, not individual VNIC groups.

Identity and Access Management (IAM) dynamic groups

Why it fails: IAM groups govern user and service permissions.

Virtual Cloud Network Route Tables

Why it fails: Route tables manage network packet routing.

OCI Object Storage Lifecycle Rules

Why it fails: Object storage lifecycle rules apply to object storage, not block volume backups.

Standard Flexible Virtual Machines

Why it fails: Standard VMs require OS patching and management.

Standard Dedicated Virtual Machine Hosts

Why it fails: Dedicated hosts require full VM and OS management.

Security Lists can reference another Security List as a rule source.

Why it fails: Security lists reference CIDR blocks, whereas NSGs can reference other NSGs.

Network Security Groups can only be used in public subnets.

Why it fails: NSGs can be used in both public and private subnets.

Security Lists do not support stateful firewall rules.

Why it fails: Both security lists and NSGs support stateful and stateless rules.

OCI Object Storage bucket (mounted as block device)

Why it fails: Object storage cannot be mounted as a block device.

OCI Container Instance storage

Why it fails: Container instances are separate compute entities, not attachable storage.

Subnets (can be regional or AD-specific)

Why it fails: Subnets are created within a single availability domain or region depending on type, so they are not exclusively regional constructs. The option is tempting because regional subnets do exist, and it would be correct if the question asked which components can span or be scoped to a region.

Compute Instances

Why it fails: Compute instances are launched into a specific availability domain or fault domain, making them AD-scoped rather than regional. It is tempting because instances consume regional networking, and would be correct if the question asked which resources are availability domain-specific.

Public Internet Cache

Why it fails: Not an OCI storage service.

Unencrypted On-Premises NAS

Why it fails: External unencrypted NAS is not an OCI native service.

Local unmanaged scratch disks

Why it fails: Scratch disks are ephemeral.

Internet Gateway DNS Forwarder

Why it fails: Internet gateways do not handle DNS resolution.

Public DNS Zone

Why it fails: Public zones are for internet-facing DNS.

Traffic Management Steering Policies

Why it fails: Steering policies route global DNS traffic based on health or geo-location.

Use Object Storage mounted as a block device

Why it fails: Object storage cannot be mounted as a block device.

Attach a single Block Volume in read/write mode to multiple instances simultaneously

Why it fails: Standard Block Volumes do not support concurrent read/write multi-attachment across VMs.

Configure Local NVMe drives as a shared cluster disk

Why it fails: Local NVMe drives are local to a single physical host.

Dynamic Routing Gateway with IPsec VPN

Why it fails: VPN is for on-premises connectivity.

Internet Gateway with NAT

Why it fails: Internet gateway routes public internet traffic.

Standard Flexible VM Shape

Why it fails: Standard Flexible VM Shapes are on-demand instances OCI does not reclaim, so you pay full price regardless of idle capacity. They suit steady production workloads needing guaranteed availability. Preemptible instances, terminable on capacity reclamation, provide the cost saving required here.

Dedicated Virtual Machine Host

Why it fails: Dedicated Virtual Machine Host gives you sole tenancy of a physical server, so OCI never reclaims it and you pay the full host rate. It suits licensing or compliance isolation. Preemptible capacity, which OCI can terminate, delivers the cost reduction the batch job needs.

Standard Bare Metal Shape

Why it fails: Standard Bare Metal Shapes provide dedicated physical servers billed at full on-demand rates, with no reclamation by OCI. They suit high-performance or licensing-bound workloads. The scenario needs preemptible instances that OCI may terminate, cutting compute costs substantially.

OCI API Gateway

Why it fails: API Gateway manages and secures REST APIs; it does not balance Layer 4 traffic or preserve client source IP addresses. It is tempting because it fronts backend services, and it would be correct when exposing APIs with authentication, throttling and rate limiting.

Dynamic Routing Gateway

Why it fails: A Dynamic Routing Gateway routes traffic between VCNs and on-premises networks; it performs no load balancing or source IP preservation. It is tempting because it handles high-throughput network traffic, and it would be correct when connecting a VCN to an on-premises network.

Public Load Balancer (Layer 7)

Why it fails: A Layer 7 public load balancer terminates HTTP connections and cannot deliver the millions of packets per second or ultra-low latency of a Layer 4 network load balancer. It is tempting because it distributes traffic, and it would be correct for HTTP path-based routing.

Standard Storage

Why it fails: Standard Storage is the hot tier for frequently accessed data, carrying no retrieval charge but the highest per-GB storage cost, so it fails the infrequent-access requirement. It would be correct for actively used, latency-sensitive objects. Infrequent access with rapid retrieval and lower retrieval costs than Archive is Infrequent Access tier.

Archive Storage

Why it fails: Archive Storage is the coldest tier: retrieval takes hours and incurs retrieval fees, contradicting the rapid-access requirement. It suits long-term compliance retention rarely read. The tier for infrequent access needing rapid retrieval with lower retrieval costs than Archive is Infrequent Access.

Boot Volume storage

Why it fails: Boot Volume storage is block storage attached to compute instances for operating systems, not an Object Storage tier, so it cannot hold objects at all. It would be correct for instance boot disks. The Object Storage tier for infrequent access with rapid retrieval and lower retrieval costs than Archive is Infrequent Access.

Specify the CIDR block of the entire VCN as the source

Why it fails: A VCN-wide CIDR source permits every subnet and host in the VCN, not just the web-tier NSG, violating least privilege. It is tempting because CIDR blocks are valid sources, but they are correct when the peer is a fixed address range rather than a dynamically changing group of instances.

Use an Internet Gateway source identifier

Why it fails: An Internet Gateway source identifier matches traffic originating from outside the VCN, so it cannot represent the web-tier NSG. It is tempting because internet gateways are valid rule sources, but they are correct when permitting inbound public traffic, not intra-VCN tier-to-tier communication.

Configure a Dynamic Routing Gateway rule

Why it fails: A Dynamic Routing Gateway rule governs connectivity to on-premises or remote networks, not ingress between NSGs inside one VCN. It is tempting because DRGs are legitimate rule components, but they are correct for hybrid or peered traffic, not for selecting a peer NSG as the source.