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Oracle Cloud AR study materials
Oracle Cloud AR study resources

Oracle Cloud AR: Designing Compute, Storage and Networking Solutions on OCI

Oracle Cloud AR · Work through your exam, one topic at a time.

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Designing Compute, Storage and Networking Solutions on OCI

This domain tests shape selection, storage tiering and VCN design - the concrete plumbing questions: which shape, which gateway, which volume tier, and what fails when you cross an AD boundary.

Compute

  • VM, bare metal and flexible shapes; flexible shapes let you set OCPU and memory independently within published limits.
  • On x86, 1 OCPU = 1 physical core = 2 vCPUs; on Ampere A1, 1 OCPU = 1 core. This changes sizing math.
  • Instance pools with autoscaling: metric-based (CPU, memory via agent) or schedule-based. Preemptible instances cut cost for interruptible batch work.

Storage

  • Block Volume tiers: Lower Cost, Balanced (10 VPUs/GB), High Performance (20), Ultra High Performance (30). A volume lives in one AD and attaches only to instances in that AD.
  • Object Storage: Standard, Infrequent Access, Archive, plus auto-tiering and lifecycle policies; versioning for protection.
  • File Storage for shared POSIX workloads across instances.

Networking

  • A VCN can use /16 down to /28; subnets can be regional or AD-specific. Gateways: Internet, NAT, Service, DRG, Local Peering. FastConnect for dedicated private connectivity; site-to-site VPN as the cheaper fallback.
  • Load Balancer is flexible-bandwidth and needs a regional subnet for regional coverage; Network Load Balancer for extreme throughput and preserving source IP.

Worked example

A stateless API needs 2 OCPUs and 32 GB per node, bursting to six nodes. Choose VM.Standard.E4.Flex at 2 OCPU / 32 GB, placed in an instance pool across two ADs behind a regional flexible load balancer, with metric-based autoscaling on CPU. Put the shared uploads in Object Storage Standard with a lifecycle rule to Infrequent Access after 30 days. Reasoning: flexible shapes avoid paying for unused memory-bound ratios, and Object Storage removes the AD-pinning problem block volumes would create.

Traps

NAT gateways do not accept inbound connections. Two VCNs need a DRG or local peering - there is no implicit routing. Block volumes cannot be resized downward or attached across ADs.