Free and Premium Oracle 1z0-1124-25 Dumps Questions Answers

Problem: OKE pods can’t resolve private DB IP despite VCN DNS working.

Option A: CoreDNS in OKE must forward to VCN’s resolver for private IPs; misconfiguration is a common issue—correct.

Option B: Security lists block traffic, not resolution; VCN DNS isn’t hosted on the DB—incorrect.

Option C: Public endpoint affects API access, not internal DNS—incorrect.

Option D: Route tables don’t control DNS resolution—incorrect.

Conclusion: Option A is the most probable cause.

Oracle notes:

"CoreDNS in OKE must be configured to forward queries to the VCN’s DNS resolver (.169 address) for private IP resolution."This supports Option A. Reference:OKE DNS Configuration - Oracle Help Center(docs.oracle.com/en-us/iaas/Content/ContEng/Tasks/contengdns.htm).

Zero Trust Principles:Require explicit, identity-based access controls at every network stage.

Evaluate OCI Services:

Internet Gateway:Enables public internet access, no identity-based control.

Service Gateway:Provides private service access, no granular routing control.

NSGs:Offer stateful, identity-based rules at the VNIC level.

DRG:Facilitates routing, not identity-based access control.

NSG Fit:NSGs allow rules based on VNIC identity, source/destination IP, and ports, aligning with Zero Trust.

Conclusion:NSGs are the best fit for granular, identity-based routing control.

NSGs are pivotal for Zero Trust in OCI. The Oracle Networking Professional study guide states, "Network Security Groups provide granular, stateful security rules that can be applied to specific VNICs, enabling identity-based access controls essential for Zero Trust architectures" (OCI Networking Documentation, Section: Network Security Groups). Unlike security lists (subnet-level), NSGs offer instance-level precision.

Objective: Identify the OCI resource for private, low-latency VCN-to-VCN connectivity in the same region.

Option A: DRG connects VCNs to external networks (e.g., on-premises) or across regions, not for same-region peering—incorrect.

Option B: LPG is designed for private peering of VCNs within the same region, ensuring low-latency communication—correct.

Option C: Internet Gateway provides public internet access, not private connectivity—incorrect.

Option D: Service Gateway connects VCNs to OCI services, not other VCNs—incorrect.

Conclusion: Option B is the appropriate resource.

Oracle documentation states:

"A Local Peering Gateway (LPG) enables private connectivity between two VCNs in the same region, providing direct, low-latency communication."This confirms Option B. Reference:Local VCN Peering Overview - Oracle Help Center(docs.oracle.com/en-us/iaas/Content/Network/Tasks/localVCNpeering.htm).

Objective: Identify essential info for CPE to establish a Site-to-Site VPN with OCI.

Option A: Region and availability domain are for OCI resource placement, not CPE config—incorrect.

Option B: The DRG’s public IP is the VPN endpoint, and the IKE pre-shared key authenticates the tunnel—essential and correct.

Option C: OCID and compartment ID are for OCI management, not CPE setup—incorrect.

Option D: Subnet CIDRs are for routing, configured later, not for tunnel establishment—incorrect.

Conclusion: Option B provides the critical VPN connection details.

Oracle documentation states:

"To configure your CPE for Site-to-Site VPN, you need the public IP address of the DRG (VPN headend) and the IKE pre-shared key from the OCI console."This confirms Option B. Reference:Setting Up IPSec VPN - Oracle Help Center(docs.oracle.com/en-us/iaas/Content/Network/Tasks/settingupIPSec.htm).

Goal: Balance global load balancing with regional WAF protection near users.

Option A: Single WAF in one region creates a bottleneck and increases latency—insufficient.

Option B: GLB distributes globally to regional Load Balancers, each with a WAF, ensuringprotection close to users—correct.

Option C: WAF before GLB centralizes protection, adding latency and a single failure point—incorrect.

Option D: Source IP routing with regional WAFs is less optimal than GLB’s health-based routing—less effective.

Conclusion: Option B optimizes both goals.

Oracle states:

"OCI GLB distributes traffic across regions. Pair with regional Load Balancers and WAFs for localized protection and optimal performance."This supports Option B. Reference:Global Load Balancer Overview - Oracle Help Center(docs.oracle.com/en-us/iaas/Content/Balance/Concepts/globalbalance.htm).

Goal:Stable endpoint for MySQL DB with HA failover support.

Endpoint Options:

Public IP:Exposed, changes on failover; unsuitable.

DNS with Floating IP:Persistent across failovers; ideal.

Private IP:Tied to primary, fails on switch; incorrect.

Service Gateway:For OCI services, not MySQL DB; incorrect.

Evaluate Options:

A:Public exposure, no HA; incorrect.

B:Floating private IP with DNS ensures continuity; correct.

C:Static IP breaks on failover; incorrect.

D:Misaligned purpose; incorrect.

Conclusion:DNS with floating IP is most suitable.

MySQL DB in OCI uses floating IPs for HA. The Oracle Networking Professional study guide explains, "A DNS hostname resolving to the floating private IP of the active MySQL Database Service instance ensures seamless connectivity during failover events" (OCI Networking Documentation, Section: MySQL Database Service HA). This provides predictability and stability.

Problem:DNSSEC validation fails post-setup.

DNSSEC Chain:Requires DS record in parent zone for trust.

Evaluate Causes:

A:Low TTL affects caching, not validation; unlikely.

B:Missing DS in parent zone breaks chain; most likely.

C:Resolver config is client-side, not affecting external tools; incorrect.

D:OCI uses standard algorithms; highly unlikely.

Conclusion:Registrar delay in publishing DS is the primary cause.

DNSSEC relies on the parent zone. The Oracle Networking Professional study guide explains, "DNSSEC validation fails if the registrar hasn’t published the DS record in the parent zone, as this breaks the chain of trust" (OCI Networking Documentation, Section: DNSSEC Troubleshooting). This is a common post-enablement issue.

Context: Zero Trust assumes no trust, requiring strict isolation (micro-segmentation).

Option A: Bandwidth isn’t increased by segmentation—incorrect.

Option B: Segmentation may increase route tables for granularity, not reduce them—incorrect.

Option C: Micro-segmentation isolates workloads, limiting breach impact (blast radius)—core Zero Trust goal and correct.

Option D: Inter-region connectivity isn’t simplified by micro-segmentation—incorrect.

Conclusion: Option C aligns with Zero Trust principles.

Oracle notes:

"Micro-segmentation in OCI VCNs, using NSGs and security lists, limits the blast radius of breaches by isolating resources, a key Zero Trust principle."This supports Option C. Reference:Zero Trust in OCI - Oracle Help Center(docs.oracle.com/en-us/iaas/Content/Network/Concepts/zerotrust.htm).

Goal:Prefer FastConnect routes over public internet in OCI.

BGP Attributes:

Local Preference:Higher value prefers a path within an AS.

AS Path:Shorter path preferred, but manipulated on sender side.

Prefix Length:More specific wins, but not controllable here.

MED:Influences inbound traffic, not OCI preference.

Evaluate Options:

A:Higher Local Preference ensures FastConnect priority; correct.

B:AS Path is set by on-premises, not OCI; incorrect.

C:Prefix specificity is on-premises controlled; incorrect.

D:MED affects on-premises, not OCI; incorrect.

Conclusion:Local Preference is the right attribute.

Local Preference controls route preference in BGP. The Oracle Networking Professional study guide states, "To prioritize FastConnect routes in OCI, increase the Local Preference for routes learned via the FastConnect virtual circuit over other paths" (OCI Networking Documentation, Section: BGP Configuration). This ensures OCI prefers the private path.

Objective: Improve OCI-AWS data transfer performance.

Option A: Region distance affects latency—valid.

Option B: Dedicated interconnect boosts bandwidth and stability—valid.

Option C: Compute pricing doesn’t influence inter-cloud bandwidth—invalid.

Option D: WAN optimization can enhance transfer efficiency—valid.

Conclusion: Option C is not a design consideration for performance.

Oracle notes:

"To optimize OCI-AWS connectivity, consider region proximity, dedicated interconnects, or WAN optimization. Compute pricing is unrelated to network performance."This excludes Option C. Reference:Hybrid Cloud Networking - Oracle Help Center(docs.oracle.com/en-us/iaas/Content/Network/Concepts/hybridcloud.htm).

Needs: Private, dedicated connection for large data transfers to Object Storage.

Option A: VPN with Service Gateway uses public internet, limiting bandwidth—incorrect.

Option B: Internet Gateway exposes traffic publicly—incorrect.

Option C: FastConnect Private Peering provides a dedicated link, and Service Gateway ensures private Object Storage access—correct.

Option D: DRG with Internet Gateway isn’t private—incorrect.

Conclusion: Option C best meets the need.

Oracle states:

"FastConnect Private Peering combined with a Service Gateway enables secure, high-bandwidth access to Object Storage from on-premises networks."This supports Option C. Reference:FastConnect and Service Gateway - Oracle Help Center(docs.oracle.com/en-us/iaas/Content/Network/Tasks/fastconnect.htm#servicegateway).

Requirement Analysis: Strict compliance mandates logging all user access to private resources in a multi-tier setup.

Option A Assessment: Dynamic port forwarding with no logging fails compliance, as it provides no audit trail.

Option B Assessment: Managed Bastion sessions in OCI offer detailed logging (e.g., session start/end times, user IDs), integrated with OCI Logging. This meets compliance needs with a managed, scalable solution.

Option C Assessment: SSH port forwarding with minimal logs doesn’t provide the detailed auditing required for strict compliance.

Option D Assessment: A jump server with manual logging is error-prone, lacks scalability, and isn’t a managed OCI service, making it less suitable.

Conclusion: Option B provides the most robust, compliance-ready solution with detailed logging.

From Oracle’s Bastion documentation:

"OCI Bastion provides managed SSH sessions with detailed logging capabilities, capturing user access details for audit and compliance. Enable session logging to record all activities."This supports Option B as the best choice. Reference:Bastion Service Overview - Oracle Help Center(docs.oracle.com/en-us/iaas/Content/Bastion/Concepts/bastionoverview.htm).

Objective:Enable transitive routing via a network appliance (e.g., firewall) between VCNs.

Transitive Routing Setup:DRG connects VCNs; appliance processes traffic.

Key Requirement:DRG must route traffic to the appliance’s private IP.

Evaluate Options:

A:Service Gateway is for OCI services, not transitive routing; incorrect.

B:Static routes on DRG to appliance ensure correct traffic flow; essential.

C:Load Balancer is optional, not essential for routing; incorrect.

D:LPG is for intra-region VCN peering, not appliance-DRG connection; incorrect.

Conclusion:DRG static routes to the appliance are critical for transitive routing.

Transitive routing with a network appliance requires explicit routing configuration. The Oracle Networking Professional study guide notes, "To enable transitive routing through a network appliance, configure static routes in the DRG route table pointing to the appliance’s private IP as the next hop" (OCI Networking Documentation, Section: Transitive Routing with DRG). This ensures traffic is processed by the appliance between VCNs.

Requirement:Private VCN connection across tenancies.

Services:

Internet Gateway:Public access; incorrect.

Service Gateway:OCI services, not VCNs; incorrect.

RPC:Cross-tenancy private peering; correct.

DRG with LPG:LPG is intra-region, not cross-tenancy; incorrect.

Evaluate Options:

A:Public; incorrect.

B:Service-focused; incorrect.

C:Designed for this scenario; correct.

D:Misaligned components; incorrect.

Conclusion:RPC is the right service.

RPC enables cross-tenancy peering. The Oracle Networking Professional study guide notes, "Remote Peering Connections (RPCs) establish private connectivity between VCNs in different tenancies over OCI’s private backbone" (OCI Networking Documentation, Section: Remote Peering Connections). This ensures no public internet traversal.

Requirement Analysis: The solution needs a private, high-bandwidth, low-latency connection (provided by FastConnect) with encryption for data confidentiality.

Option A (IPSec VPN): IPSec encrypts traffic at Layer 3 over public or private networks. While feasible over FastConnect, it’s redundant since FastConnect is already private, adding unnecessary overhead and complexity.

Option B (OCI Vault): Vault manages encryption keys and secrets but doesn’t encrypt traffic itself—only supports application-level encryption, not link-level—incorrect.

Option C (MACsec): MACsec (Media Access Control Security) provides Layer 2 encryption for Ethernet traffic, ideal for securing FastConnect’s dedicated link directly between devices, ensuring confidentiality without higher-layer overhead—correct.

Option D (OCI Bastion): Bastion secures remote access to VCN resources, not link encryption—incorrect.

Conclusion: MACsec enhances FastConnect with efficient, link-level encryption, meeting all requirements.

Oracle documentation states:

"MACsec provides Layer 2 encryption for FastConnect, securing Ethernet traffic between on-premises and OCI infrastructure. It’s ideal for ensuring confidentiality over dedicated connections."This supports Option C as the best additional product. Reference:FastConnect Security Options - Oracle Help Center(docs.oracle.com/en-us/iaas/Content/Network/Tasks/fastconnect.htm#security).

Requirement: Secure outbound connection to a public API without exposing the instance.

Option A: Internet Gateway allows inbound and outbound traffic, exposing the instance—violates policy.

Option B: NAT Gateway enables outbound-only internet access from a private subnet. A security list restricts traffic to the API’s IP, ensuring security—correct.

Option C: Service Gateway is for OCI services, not third-party APIs—incorrect.

Option D: DRG with FastConnect is for private connections (e.g., on-premises), not internet APIs—incorrect.

Conclusion: Option B meets the policy and connectivity needs.

Oracle notes:

"A NAT Gateway allows instances in a private subnet to initiate outbound internet traffic without receiving inbound connections. Use security lists to restrict destinations."This supports Option B. Reference:NAT Gateway Overview - Oracle Help Center(docs.oracle.com/en-us/iaas/Content/Network/Tasks/NATgateway.htm).

Objective: Identify the OCI component for dynamic routing in a hybrid setup.

Option A: Internet Gateway enables public internet access, not private hybrid routing—incorrect.

Option B: DRG is a virtual router that dynamically routes traffic between on-premises networks and VCNs via FastConnect or VPN, using protocols like BGP—correct.

Option C: Service Gateway provides private access to OCI services, not on-premises connectivity—incorrect.

Option D: LPG peers VCNs within the same region, not with on-premises—incorrect.

Conclusion: DRG is essential for hybrid dynamic routing.

Oracle documentation confirms:

"The Dynamic Routing Gateway (DRG) enables dynamic routing between your on-premises network and VCNs, supporting hybrid cloud connectivity via FastConnect or VPN."This validates Option B. Reference:Dynamic Routing Gateway Overview - Oracle Help Center(docs.oracle.com/en-us/iaas/Content/Network/Tasks/managingDRGs.htm).

Goal:Minimize downtime in blue/green deployment with ALB.

ALB Capabilities:Supports weighted routing for gradual traffic shifts.

Evaluate Options:

A:Immediate switch risks downtime if ‘green’ fails; less efficient.

B:Listener swap causes abrupt change; not optimal.

C:Gradual shift with weights ensures smooth transition; most efficient.

D:Forcing ‘blue’ unhealthy is disruptive and hacky; inefficient.

Conclusion:Weighted routing provides the smoothest transition.

ALB supports blue/green via routing rules. The Oracle Networking Professional study guide states, "Application Load Balancer’s routing rules allow weighted traffic distribution between backend sets, enabling blue/green deployments with minimal downtime" (OCI Networking Documentation,Section: Load Balancer Routing). This method ensures stability during updates.

Requirements:Private, encrypted connectivity to on-premises, no public internet.

Gateway Options:

Service Gateway:For OCI services, not on-premises.

Internet Gateway:Public internet access, unsuitable.

DRG with FastConnect:Private on-premises connectivity.

NAT Gateway:Outbound internet, not private to on-premises.

Evaluate Options:

A:Limited to OCI services; incorrect.

B:Uses public internet; violates policy.

C:FastConnect via DRG ensures private, encrypted link; correct.

D:Public IPs contradict requirement; incorrect.

Conclusion:DRG with FastConnect is the most appropriate.

FastConnect provides private connectivity via DRG. The Oracle Networking Professional study guide states, "A Dynamic Routing Gateway with FastConnect establishes a dedicated, private connection to on-premises networks, ensuring data encryption and isolation from the public internet" (OCI Networking Documentation, Section: FastConnect). This meets security and privacy needs.

Requirement:Transitive routing across regions and to on-premises, privately.

Components:

LPG:Intra-region VCN peering; limited scope.

DRG:Cross-region and on-premises routing via private backbone.

Service Gateway:OCI service access; not transitive.

Internet Gateway:Public internet; not private.

Evaluate Options:

A:Region-specific; incorrect.

B:Supports multi-region and on-premises; correct.

C:Service-focused; incorrect.

D:Public; incorrect.

Conclusion:DRG is the key component.

DRG enables complex routing scenarios. The Oracle Networking Professional study guide notes, "The Dynamic Routing Gateway (DRG) facilitates transitive routing between VCNs in different regions and on-premises networks over OCI’s private backbone" (OCI Networking Documentation, Section: Dynamic Routing Gateway). This meets both requirements efficiently.

Zero Trust Context:Assumes no inherent trust, requiring explicit controls at all network stages.

Evaluate Principles:

Implicit Trust:Assumes trust, opposite of Zero Trust; incorrect.

Least Privilege:Grants minimal access, explicitly enforced; aligns with Zero Trust.

Perimeter Security:Relies on boundary protection, not Zero Trust; incorrect.

Network Segmentation:Isolates networks, a tactic not a principle; incomplete.

Conclusion:Least Privilege is the core principle for explicit access control.

Zero Trust Packet Routing in OCI emphasizes Least Privilege. The Oracle Networking Professional study guide states, "The Least Privilege principle in Zero Trust requires that access controls be explicitly defined and enforced at every network communication stage, ensuring no implicit trust" (OCI Networking Documentation, Section: Zero Trust Networking). This drives granular security policies.

Requirements: Outbound internet access, no inbound exposure, and private OCIR access.

Option A: Internet Gateway allows inbound traffic, violating the no-exposure rule—incorrect.

Option B: NAT Gateway enables outbound-only internet access, but Internet Gateway adds inbound exposure—incorrect.

Option C: NAT Gateway provides outbound internet access without inbound exposure; Service Gateway enables private OCIR access—correct.

Option D: DRG is for external networks, not internet/OCIR access; Internet Gateway exposes servers—incorrect.

Conclusion: Option C satisfies all requirements.

Oracle states:

"Use a NAT Gateway for outbound internet access from private subnets without inbound connectivity. Use a Service Gateway for private access to OCI services like OCIR."This supports Option C. Reference:NAT and Service Gateway Overview - Oracle Help Center(docs.oracle.com/en-us/iaas/Content/Network/Tasks/NATgateway.htm & docs.oracle.com/en-us/iaas/Content/Network/Tasks/servicegateway.htm).

Requirements: HA and IPv6 support for public web app.

Option A: ULA is private, not routable; NAT for IPv6 is inefficient—incorrect.

Option B: ULA doesn’t support public IPv6 clients—incorrect.

Option C: Public IPv6 CIDR is correct, but IPv4-only LB with NAT lacks direct IPv6—less resilient.

Option D: Public IPv6 CIDR with dual-stack LB and instances ensures full IPv6 support and HA across ADs—correct.

Conclusion: Option D maximizes resilience and connectivity.

Oracle states:

"For public IPv6 applications, use a public IPv6 CIDR block and configure Load Balancers and instances for both IPv4 and IPv6 to ensure resilience."This supports Option D. Reference:IPv6 in OCI - Oracle Help Center(docs.oracle.com/en-us/iaas/Content/Network/Tasks/managingIPv6.htm).

Requirement: Provide VLAN config info for FastConnect setup.

Option A: CIDR blocks are for routing, not VLAN setup—incorrect.

Option B: VLAN ID defines the circuit, BGP ASN and peering IPs establish routing—essential and correct.

Option C: MTU is a performance setting, not required for VLAN config—incorrect.

Option D: OCID and compartment ID are for OCI management, not provider setup—incorrect.

Conclusion: Option B provides the necessary VLAN configuration details.

Oracle states:

"For FastConnect, provide the provider with a VLAN ID, your BGP ASN, and BGP peering IPs to configure the virtual circuit."This confirms Option B. Reference:FastConnect Configuration - Oracle Help Center(docs.oracle.com/en-us/iaas/Content/Network/Tasks/fastconnect.htm#providerconfig).

Requirements:Private subnet, no internet, access to other VCN subnets, HA database.

Analyze Components:

Public Subnet:Internet-exposed, against policy.

Private Subnet:No internet, aligns with policy.

Service Gateway:For OCI services, not ADB connectivity.

DRG:For inter-VCN routing.

NSGs:Granular traffic control.

Evaluate Options:

A:Public subnet violates no-internet policy; incorrect.

B:Service Gateway for Object Storage/Yum irrelevant to ADB; incomplete.

C:Private subnet, NSGs, DRG, and CIDR planning meet all needs; correct.

D:Public subnet with internet access; violates policy.

Conclusion:Option C is the most effective approach.

Autonomous Database requires private deployment for security. The Oracle Networking Professional study guide notes, "For Autonomous Database on Dedicated Exadata, use a private subnet with NSGs for access control and a DRG for inter-VCN connectivity, reserving CIDR for scalability" (OCI Networking Documentation, Section: Autonomous Database Networking). Service Gateway isn’t used for ADB access, but the private setup ensures compliance.

Goal:Inspect NSG rules for a VNIC from Cloud Shell.

Command Flow:

Get instance → Extract VNIC → List NSGs → Get NSG details.

Evaluate Options:

A:Direct NSG fetch lacks VNIC linkage; incomplete.

B:Full pipeline from instance to NSG details; precise and correct.

C:Grep is too basic, misses structure; incorrect.

D:Awk parsing is fragile, less reliable than jq; less optimal.

Conclusion:Option B provides the most robust inspection.

CLI with jq ensures accurate NSG retrieval. The Oracle Networking Professional study guide notes, "To troubleshoot NSG rules, use the OCI CLI to fetch instance VNIC details and associated NSG configurations, piping through jq for structured output" (OCI Networking Documentation, Section: CLI Troubleshooting). Option B follows this methodology.

Requirements:Quick, cheap, encrypted VPN; interim before FastConnect.

VPN Options:

Static VPN:Simple, native, low cost.

Third-Party Appliance:Complex, costly.

Service Gateway:Not for VPN; incorrect.

BGP VPN:Dynamic, more setup; less quick.

Evaluate Options:

A:Static VPN is fast, secure, budget-friendly; correct.

B:Appliance adds cost and complexity; incorrect.

C:Misaligned use of Service Gateway; incorrect.

D:BGP is overkill for pilot; less efficient.

Conclusion:Static VPN via DRG is most suitable.

Static VPN is ideal for quick setups. The Oracle Networking Professional study guide notes, "A Site-to-Site VPN with static routing via DRG provides a fast, encrypted connection for short-term needs, minimizing cost and setup time" (OCI Networking Documentation, Section: Site-to-Site VPN). This fits the pilot project perfectly.

Requirement:Restrict inter-subnet communication unless permitted.

Options Analysis:

A:Removing default route breaks all routing, overly restrictive; incorrect.

B:Separate VCNs are excessive, complex; less practical.

C:NSGs provide granular, explicit control; optimal approach.

D:External firewall adds complexity, not VCN-native; inefficient.

NSG Advantage:Instance-level rules enforce policy within VCN.

Conclusion:NSGs are the most appropriate solution.

NSGs enable precise security within a VCN. The Oracle Networking Professional study guide states, "Network Security Groups (NSGs) allow you to define strict ingress and egress rules for instances, ensuring inter-subnet communication is explicitly permitted as per security policies" (OCI Networking Documentation, Section: Network Security Groups). This is more efficient than VCN separation or external firewalls.

Objective: Allow VCN-A to access on-premises (192.168.1.0/24) via VPN, isolate VCN-B using DRG route tables effectively and securely.

Option A: Single route table for both VCNs with NSGs on VCN-B to block traffic. This works but relies on NSGs, which are secondary to routing. Routing-level isolation is more secure and efficient.

Option B: Single route table for VCN-A with the VPN route, default table (no VPN route) for VCN-B. This isolates VCN-B effectively at the routing level, but managing one table across all attachments can complicate scaling.

Option C: Two route tables, both with VPN routes, then blocking VCN-B with security lists. This is inefficient—routes are advertised unnecessarily, relying on security lists instead of routing isolation.

Option D: Two route tables—DRG-RT-A with VPN route for VCN-A, DRG-RT-B with no VPN route for VCN-B. This ensures VCN-B has no path to on-premises at the DRG level, providing the strongest isolation.

Conclusion: Option D is the most effective and secure, leveraging routing for isolation rather than secondary security controls.

Oracle documentation states:

"DRG route tables control traffic between VCN attachments and external connections (e.g., VPN). Associate a unique route table with each attachment to enforce specific routing policies."

"To isolate a VCN, ensure its DRG route table contains no routes to the destination."Option D aligns with this approach. Reference:Dynamic Routing Gateway Overview - Oracle Help Center(docs.oracle.com/en-us/iaas/Content/Network/Tasks/managingDRGs.htm).

Problem Context: BGP session is established, but no routes are exchanged, and basic config (ASNs, IPs) is correct.

Option A Analysis: Misconfigured keepalive timers would cause the session to drop intermittently. Since the session is confirmed as established, this is unlikely. Keepalives affect session stability, not route exchange.

Option B Analysis: A mismatch in BGP authentication keys (e.g., MD5 passwords) would prevent the session from establishing. Given the session is up, this is not the issue.

Option C Analysis: BGP prefix lists or route maps filter advertised routes. If either the on-premises router or OCI applies a filter (intentionally or misconfigured), it could block route advertisements despite an established session. This is a common issue in BGP setups and aligns with the symptoms.

Option D Analysis: MTU mismatches could cause packet loss or fragmentation, but BGP uses TCP (small packets), and session establishment indicates MTU isn’t the primary issue. Route exchange failures are more likely due to filtering than MTU.

Conclusion: Option C is the most likely cause, as filtering directly prevents route exchange without affecting session status.

From Oracle’s FastConnect documentation:

"Once a BGP session is established, routes are exchanged based on the prefixes advertised by each side. Route maps, prefix lists, or filters on either the CPE or OCI side can restrict which routes are advertised or accepted."

"If no routes appear in the routing table despite an active session, verify that no filters are blocking advertisements."This supports Option C as the most likely cause. Reference:FastConnect Overview - Oracle Help Center(docs.oracle.com/en-us/iaas/Content/Network/Tasks/fastconnect.htm).

Objective: Identify a VPN disadvantage for large dataset migration.

Option A: VPNs can be secure with IPSec; not inherently less secure—incorrect.

Option B: VPNs are automatable with IaC (e.g., Terraform)—incorrect.

Option C: Public internet limits VPN throughput due to bandwidth and latency variability—correct disadvantage.

Option D: VPNs are compatible with OCI services—incorrect.

Conclusion: Option C is the key disadvantage.

Oracle notes:

"Public internet-based VPNs face throughput limitations due to bandwidth and latency variability, impacting large data migrations.”This supports Option C. Reference:VPN Limitations - Oracle Help Center(docs.oracle.com/en-us/iaas/Content/Network/Tasks/settingupIPSec.htm#limitations).

Goal: Apply least privilege for Cloud Shell to run diagnostics (ping, traceroute, nc) within a VCN.

Option A: Read permission on all virtual-network-family resources is too broad, granting unnecessary access beyond diagnostics—violates least privilege.

Option B: Instance Principals use temporary credentials tied to the Cloud Shell instance, enhancing security. A dynamic group with “read” and “use” permissions on NSGs and VNICs allows inspecting configurations and running diagnostics (e.g., via VNICs), meeting the exact need—correct.

Option C: Inspect permission only provides metadata access, insufficient for running diagnostics (e.g., no “use” for traffic)—incorrect.

Option D: Use permission on virtual-network-family at tenancy level is overly permissive, granting access to all network resources—violates least privilege.

Conclusion: Option B is the most restrictive and secure, aligning with least privilege.

Oracle states:

"Instance Principals allow services like Cloud Shell to authenticate without static credentials. Policies with ‘read’ and ‘use’ on specific resources (e.g., network-security-groups, vnics) enable diagnostics while adhering to least privilege."This supports Option B. Reference:Instance Principals - Oracle Help Center(docs.oracle.com/en-us/iaas/Content/Identity/Tasks/instanceprincipals.htm).

Understand the Requirement: The goal is high availability (HA) and automatic failover for a Site-to-Site VPN between an on-premises network and OCI with minimal disruption.

Evaluate Option A: A single VPN connection with one tunnel lacks redundancy. If the tunnel fails, there’s no failover mechanism, as OCI doesn’t inherently provide automatic failover for a single tunnel. This is a single point of failure.

Evaluate Option B: A single VPN connection with two tunnels using different CPE IP addresses leverages OCI’s IPSec VPN capabilities. OCI supports multiple tunnels per VPN connection, and using distinct CPE IPs (e.g., via different ISPs or devices) ensures that if one tunnel fails (due to ISP or CPE failure), the second tunnel remains active. OCI’s Dynamic Routing Gateway (DRG) automatically reroutes traffic to the active tunnel using IKE and IPSec health checks.

Evaluate Option C: Two separate VPN connections, each with one tunnel and different CPE IPs, also provide HA. Using BGP, routes are advertised redundantly. However, managing two VPN connections is more complex than a single connection with two tunnels, and BGP failover might introduce slight delays compared to IPSec tunnel failover.

Evaluate Option D: Two tunnels with the same CPE IP address within one VPN connection don’t provide true HA. If the CPE or its ISP fails, both tunnels fail, as they share a single point of failure.

Conclusion: Option B is the simplest, most resilient configuration that ensures automatic failover with minimal disruption using OCI’s native VPN capabilities.

OCI’s Site-to-Site VPN supports multiple tunnels within a single IPSec connection for redundancy. According to the Oracle Help Center:

"You can configure multiple tunnels for a single IPSec connection to provide redundancy. OCI uses IKE (Internet Key Exchange) to monitor tunnel health and automatically fails over to an active tunnel if one becomes unavailable."

"For maximum availability, use different CPE public IP addresses for each tunnel (e.g., different ISPs or devices)."This aligns with Option B, ensuring HA without the complexity of separate VPN connections or BGP. Reference:Site-to-Site VPN Overview - Oracle Help Center(docs.oracle.com/en-us/iaas/Content/Network/Tasks/settingupIPSec.htm).

Objective:Efficiently propagate on-premises route updates to multiple VCNs.

DRG Capabilities:Supports route distribution to attached VCNs.

Analyze Options:

A:Manual updates are inefficient and error-prone; unsuitable.

B:Centralized DRG with route distribution automates propagation; efficient.

C:Multiple DRGs add complexity and manual effort; inefficient.

D:Service Gateway is for OCI services, not route updates; incorrect.

Conclusion:Centralized DRG with route distribution is the most efficient method.

Route distribution in a DRG simplifies multi-region routing. The Oracle Networking Professional study guide notes, "Using a centralized DRG with route distribution enabled allows routes learned from on-premises networks to be automatically propagated to all attached VCNs, reducing management overhead" (OCI Networking Documentation, Section: DRG Route Distribution). This leverages OCI’s automation capabilities.

Requirements: Low latency, high bandwidth for multicloud production.

Option A: Dedicated peering via third-party provider offers high performance—optimal.

Option B: IPSec VPNs over public internet have variable latency and limited bandwidth—least optimal.

Option C: FastConnect peering with partners ensures dedicated performance—optimal.

Option D: OCI-Azure Interconnect is fast, but VPN to AWS adds latency—less optimal than A or C but better than B.

Conclusion: Option B is the least optimal due to performance constraints.

Oracle notes:

"IPSec VPNs over public internet provide security but lack the bandwidth and latency consistency of dedicated connections like FastConnect for production workloads.”This supports Option B as least optimal. Reference:Multicloud Connectivity Options - Oracle Help Center(docs.oracle.com/en-us/iaas/Content/Network/Concepts/multicloud.htm#options).

Problem: Instances with IPv6-only traffic can’t ping external IPv6 addresses despite FastConnect and IPv6 prefixes.

Option A: OCI supports Bring Your Own IP (BYOIP) for IPv6, including global unicast addresses, so this is incorrect.

Option B: NAT Gateways are for IPv4 outbound traffic, not IPv6—irrelevant here.

Option C: For IPv6-only instances to reach external IPv6 addresses (beyond FastConnect),an Internet Gateway (IGW) is required with a default route (::/0) in the subnet route table. This enables public IPv6 connectivity—correct.

Option D: Service Gateway is for OCI services, not general IPv6 internet access—incorrect.

Conclusion: Option C fixes the issue by enabling IPv6 internet access.

Oracle states:

"To enable IPv6 traffic to the internet, attach an Internet Gateway to the VCN and add a route rule for ::/0. OCI supports BYOIP for public IPv6 prefixes."This aligns with Option C. Reference:IPv6 in OCI - Oracle Help Center(docs.oracle.com/en-us/iaas/Content/Network/Tasks/managingIPv6.htm).