3V0-25.25 Exam Dumps - VMware Professional Level Exams Questions and Answers

Comprehensive and Detailed 250 to 350 words of Explanation From VMware Cloud Foundation (VCF) documents:

With the introduction of theVirtual Private Cloud (VPC)consumption model inVCF 9.0and late 5.x releases, Role-Based Access Control (RBAC) has become more granular to support true multi-tenancy. A VPC is designed to be a self-contained "container" for a department's or user's networking resources.

To meet the specific requirement where a user can configure aspects of an individual VPC but is restricted from creating new subnets (which involves modifying the underlying network CIDR blocks and IPAM), a combination of specific roles is required.

VPC Admin:This is the primary role for the user within their assigned VPC. It allows the user to manage the overall VPC environment, including high-level settings and monitoring. However, the VPC Admin's power is often limited by the specific quotas and policies set by the Enterprise Admin.

Security Operator:This role allows the user to view security configurations and policies without having the permission to modify the network fabric or create new infrastructure components like subnets. It provides the "read-only" visibility into the security posture of the VPC.

Network Operator:Similar to the Security Operator, the Network Operator role provides visibility into the networking state—such as routing tables, segment status, and connectivity—without granting the "Write" permissions required to provision new subnets or alter the network topology.

AssigningNetwork Admin(Option B) orSecurity Admin(Option A) would grant too much privilege, as these roles typically include the ability to create, delete, and modify subnets and firewall policies at a structural level. By combining theVPC Adminrole withOperator-level roles, the administrator ensures the user has the necessary context to manage their assigned resources while strictly adhering to the restriction against creating new network subnets.

P1 and P2 interfaces on EN2

In aVMware Cloud Foundation (VCF)environment, the interaction between different tiers of logical gateways is governed by the placement ofService Routers (SR). When a Tier-1 Gateway is configured with stateful services, such as aGateway Firewall (GFW), it must operate inActive/Standby (A/S)mode. This ensures that session state is maintained on a single active node at any given time.

According to the provided diagram and VCF architectural guidelines, theActive Tier-1 SRis hosted onEdge Node 2 (EN2). In a multi-tier NSX design, the Tier-1 gateway is logically connected to the Tier-0 gateway via an internal transit segment (often referred to as the Router Link). While the Tier-0 gateway itself is running inActive/Active (A/A)mode across all nodes (EN1 through EN4) to provide high-bandwidth ECMP to the physical Top-of-Rack (ToR) switches, the Tier-1's path to the external world is constrained by its own current location.

Traffic originating from a workload segment attached to this Tier-1 will be processed by the GFW onEN2. From there, the packet must exit to the physical network via the Tier-0 uplinks. Because the Tier-1 SR is localized to EN2, it will utilize the local Tier-0 instances and their corresponding physical uplinks located on that same node to avoid unnecessary inter-edge "East-West" hair-pinning over the Geneve overlay.

The highlighted optionsP1 and P2 on EN2represent the specific physical/logical uplink paths (VLAN-backed) that the Tier-1 GFW on EN2 will use to reachToR A and ToR B. Even though EN1, EN3, and EN4 also have active Tier-0 paths, the stateful nature of the Tier-1 on EN2 means its North-South traffic flow is anchored to the uplinks of its current host node. Therefore, to identify the ECMP paths actively utilized by that specific stateful Tier-1 service, the administrator must look at the uplink interfaces (P1/P2) associated with the node where that Tier-1 is active.

Active-Standby Tier-0 Gateway

Active-Standby Tier-1 Gateway

In aVMware Cloud Foundation (VCF)multi-site or multi-instance architecture, established viaNSX Federation, secure connectivity between sites is often achieved throughIPSec VPN. IPSec VPN is considered a stateful service within the NSX networking stack.

Stateful services—which also include NAT and Load Balancing—require a centralized point of processing to maintain the security association (SA) and session state tables. In the NSX gateway architecture, this necessitates the presence of aService Router (SR)component. For stateful consistency and to avoid session disruption that would occur if asymmetric traffic were processed by different nodes, these gateways must operate in anActive-Standbyhigh-availability mode.

According to the "NSX-T Data Center VPN Configuration Guide," IPSec VPN services can be deployed on either the provider tier (Tier-0 Gateway) or the tenant tier (Tier-1 Gateway). When configured on a Tier-0 gateway, the VPN typically provides broad connectivity between the physical infrastructure of two sites. When configured on a Tier-1 gateway, it often provides targeted connectivity for a specific project or department's workload segments.

Configurations involvingActive-Activegateways (whether Tier-0 or Tier-1) do not support the native NSX IPSec VPN service because the ECMP (Equal Cost Multi-Pathing) nature of Active-Active mode could lead to packets belonging to the same VPN tunnel being processed by different Edge nodes, which cannot share the real-time encryption state. Therefore, for an administrator to successfully implement a cross-location VPN in a VCF Fleet, they must ensure the target gateway—be it Tier-0 or Tier-1—is deployed inActive-Standbymode.

Comprehensive and Detailed 250 to 350 words of Explanation From VMware Cloud Foundation (VCF) documents:

In the context ofVMware Cloud Foundation (VCF), particularly versions 5.x and the architectural advancements inVCF 9.0, the establishment of North-South routing via theNSX Tier-0 Gatewayis a critical post-deployment or bring-up task. The Tier-0 gateway usesBorder Gateway Protocol (BGP)to peer with physical Top-of-Rack (ToR) switches to exchange reachability information for the overlay networks.

When a BGP session is reported in the"Idle"state, it indicates that the BGP Finite State Machine (FSM) is at its first stage and is not yet attempting a TCP connection, or it has encountered an error that forced it back to this state. According to VMware VCF documentation and NSX troubleshooting guides, if the administrator can successfully ping between the Tier-0 uplink IP and the physical router interface,Layer 3 reachability is confirmed. This eliminates issues related to physical cabling, VLAN tagging on the trunk ports, or basic IP interface configuration.

The primary reason a BGP session remainsIdledespite successful ICMP reachability is a configuration mismatch. Specifically, anAutonomous System (AS) number mismatchis the most frequent culprit. BGP requires that the "Remote AS" configured on the Tier-0 gateway matches the "Local AS" of the physical peer. If the SDDC Manager automated workflow or the manual configuration in NSX Manager contains a typo in these values, the protocol handshake will fail immediately.

While aDistributed Firewall (DFW)could technically block port 179, it is not common in a "freshly deployed" environment for the default rules to block the Edge Node's control plane traffic.Geneve tunnelsandMTU issues(Option C and D) typically affect the data plane—causing packet loss for encapsulated guest VM traffic—but they do not prevent the BGP control plane (running over standard TCP) from moving beyond the Idle state. Therefore, verifying the AS numbers in the VCF Planning and Preparation Workbook against the physical switch configuration is the verified resolution path.

Comprehensive and Detailed 250 to 350 words of Explanation From VMware Cloud Foundation (VCF) documents:

In aVMware Cloud Foundation (VCF)Federation deployment across multiple sites, the management architecture is designed to provide "Global Visibility" while maintaining "Local Autonomy." This is achieved through the coordinated distribution ofGlobal Managers (GMs)andLocal Managers (LMs).

For a three-site deployment,NSX Federationbest practices mandate that each site maintains its ownLocal Manager (LM) Cluster(Option A). The LM is responsible for the site-specific control plane, communicating with local Transport Nodes (ESXi and Edges) to program the data plane. If the connection to the GM is lost, the LM ensures the local site continues to function normally. For production environments, these must be clusters (typically 3 nodes) rather than single nodes to ensure local management remains available.

To protect theGlobal Manageritself—which is the source of truth for all global networking and security policies—the GM cluster should bestretched across the three sites(Option D). In a standard 3-node GM cluster, placing one node at each site ensures that the Federation management plane can survive the complete failure of an entire site. This "stretched" cluster configuration provides a high level of resilience and ensures that an administrator can still manage global policies from any surviving location.

Option B is incorrect because the GM does not communicate directly with the data plane of a site; it must go through an LM. Option C is a risk to availability. Option E is incorrect because vSphere HA cannot protect against a site-wide disaster, and a single appliance represents a significant single point of failure for the entire global network configuration.

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Comprehensive and Detailed 250 to 350 words of Explanation From VMware Cloud Foundation (VCF) documents:

InVMware Cloud Foundation (VCF), the lifecycle of the NSX Manager cluster is strictly managed bySDDC Manager. During the initial deployment of a Management Domain or the creation of a new Workload Domain (if using a separate NSX instance), the administrator selects a "Form Factor" (Small, Medium, Large, or Extra Large) based on the expected scale of the environment.

As of current VCF versions (including 5.x), theForm Factoris a parameter defined during the deployment workflow that determines the resource reservations (CPU/RAM) and the disk partitioning of the appliance OVA. Unlike a standard virtual machine where you might simply adjust the vCPU and RAM settings in vCenter, the NSX Manager appliance is an opinionated system. Changing resources manually through vCenter (Option C) is not supported and can lead to stability issues or "Out of Sync" errors within SDDC Manager, as the database and internal services are tuned for the specific size selected at install.

There is currently no supported "in-place" upgrade or downgrade for the form factor of an existing NSX Manager node via the UI or API (Option B). To change the size, the administrator mustredeploythe manager nodes. In a VCF context, this often involves using SDDC Manager to delete the cluster or manually replacing nodes one by one—essentially deploying a new node of the correct size, joining it to the management cluster, syncing the data, and then removing the old, oversized node.

VCF Operations(formerly vRealize Operations) can provide "Right-sizing"recommendations(Option D), but it cannot execute the physical resizing of an NSX Manager appliance within the VCF framework. Therefore, the manual or orchestrated redeployment of the nodes is the only verified method to change the appliance footprint.

Comprehensive and Detailed 250 to 350 words of Explanation From VMware Cloud Foundation (VCF) documents:

In aVMware Cloud Foundation (VCF)environment, the NSX Management Cluster consists of three nodes to ensure high availability and quorum. When a single node fails and is subsequently replaced—either through a manual deployment or an orchestrated recovery viaSDDC Manager—the internal database (Corfu) and the cluster manager must be updated to reflect the current members of the cluster.

When a node is lost or manually deleted from vCenter without being properly decommissioned through the NSX API or CLI, the remaining "Leader" node retains the metadata and theUUIDof that missing member. Even after a new node joins the cluster and synchronizes data, the cluster state often remains in a"Degraded"status because the control plane still expects a response from the original, failed UUID.

According to NSX troubleshooting and recovery guides, the specific command to purge a stale or defunct member from the cluster configuration isdetach node <UUID>. This command must be executed from the CLI of the current Cluster Leader. By running detach node , the administrator instructs the cluster manager to permanently remove the record of the failed node from the management plane's membership list.

Option B and C are incorrect because "delete node" is not the primary CLI command used for cluster membership cleanup; "detach" is the specific primitive required to break the logical association. Option A would remove the healthy new node, worsening the situation. Once the stale UUID is detached, the cluster status should transition from "Degraded" to "Stable" as it no longer tries to communicate with the non-existent entity. This process is essential in VCF operations to maintain a healthy "green" status in both the NSX Manager and the SDDC Manager dashboard.

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Comprehensive and Detailed 250 to 350 words of Explanation From VMware Cloud Foundation (VCF) documents:

InVMware Cloud Foundation (VCF), theNSX Manageruses the SFTP protocol to securely transfer configuration backups to an external repository. SFTP is built on top of the SSH protocol, which relies on a "Trust on First Use" (TOFU) model for verifying the identity of the remote host.

When an NSX Manager first connects to an SFTP server, it retrieves the server'sSSH Public Key Fingerprintand stores it in its local known_hosts equivalent database. This fingerprint ensures that future connections are made to the same, verified server, preventing man-in-the-middle attacks.

The error"Host KEY Verification Failed"occurs when the administrator changes the SFTP server (or if the SFTP server's OS was reinstalled/keys regenerated). Even if the IP address remains the same, the new server presents a different SSH fingerprint than the one currently cached in the NSX Manager configuration. Because the signatures do not match, the NSX Manager aborts the connection for security reasons.

To resolve this issue, the administrator mustUpdate the SSH fingerprint(Option B) within the NSX Manager backup settings. This involves:

Retrieving the new fingerprint from the SFTP server (e.g., via ssh-keyscan).

Navigating to System > Lifecycle > Backup & Restore in the NSX Manager.

Editing the File Server configuration and pasting the new fingerprint into the appropriate field.

Option A is incorrect as it does not address the SSH protocol handshake failure. Option C is incorrect because SFTP/SSH uses fingerprints, not SSL/TLS certificates. Option D is irrelevant as it changes the source/destination of the connection but does not fix the underlying trust mismatch. Therefore, updating the fingerprint is the verified operational step to restore the automated backup workflow in VCF.