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Cisco DCAUTO 300-635 practice questions

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Question 1Data Center Automation and Programmability Fundamentals

Which Cisco platform provides a controller-based, intent-driven fabric for data center networks and exposes a REST API for automation?

  1. Cisco Nexus Dashboard (with Nexus Dashboard Fabric Controller) Correct answer.
  2. Cisco DNA Center
  3. Cisco Intersight
  4. Cisco Identity Services Engine

Explanation

Nexus Dashboard with Nexus Dashboard Fabric Controller is Cisco's data center fabric controller that manages Nexus switches and exposes REST APIs for automation. The other products serve different roles: policy/identity, campus intent, and compute management respectively.

Question 2Data Center Automation and Programmability Fundamentals

In a Cisco ACI fabric, which construct groups endpoints that share the same policy requirements and network services?

  1. Endpoint Group (EPG) Correct answer.
  2. Tenant
  3. Fabric Extender Profile
  4. Bridge Domain

Explanation

An Endpoint Group (EPG) is a logical collection of endpoints with common policy requirements, and it is the primary object to which contracts are applied. Bridge Domains provide Layer 2/Layer 3 forwarding, tenants are policy containers, and fabric extender profiles are for FEX connectivity.

Question 3Data Center Automation and Programmability Fundamentals

Which Cisco ACI feature lets you define connectivity and services as a reusable template that can be deployed repeatedly across tenants?

  1. Contracts
  2. Bridge Domain
  3. Endpoint Group
  4. Service Graph Templates Correct answer.

Explanation

Service Graph Templates describe an ordered set of service devices and connections that can be reused across deployments. Contracts define allowed communication, while EPGs and Bridge Domains are basic policy and forwarding objects.

Question 4Data Center Automation and Programmability Fundamentals

Which data model format is the native encoding used by Cisco NX-OS NETCONF and RESTCONF interfaces for configuration data?

  1. YANG-modeled XML or JSON Correct answer.
  2. Protobuf
  3. INI
  4. CSV

Explanation

YANG is the modeling language, and NETCONF/RESTCONF encode data in XML or JSON depending on the transport and device support. CSV, INI, and Protobuf are not the native encodings for these interfaces.

Question 5Data Center Automation and Programmability Fundamentals

Which HTTP methods are typically used in RESTCONF to retrieve and to create or replace configuration data?

  1. POST to retrieve and PATCH to replace
  2. GET to retrieve and PUT to create or replace Correct answer.
  3. HEAD to retrieve and DELETE to replace
  4. OPTIONS to retrieve and TRACE to replace

Explanation

RESTCONF maps CRUD operations onto HTTP methods: GET reads data, and PUT creates or replaces a resource. POST creates a resource, PATCH merges, and DELETE removes; HEAD, OPTIONS, and TRACE are not used for configuration changes.

Question 6Data Center Automation and Programmability Fundamentals

What is the primary purpose of the Cisco ACI object model's Managed Object (MO) hierarchy?

  1. To encrypt tenant traffic end to end
  2. To represent fabric configuration as a tree of addressable objects Correct answer.
  3. To define the physical power budget of leaf switches
  4. To store packet captures from fabric interfaces

Explanation

The ACI object model represents every configurable element as a managed object arranged in a tree, each addressable by a distinguished name. Packet capture, power budgeting, and encryption are separate features not provided by the MO hierarchy itself.

Question 7Data Center Automation and Programmability Fundamentals

In Python, which library is commonly used to send HTTP requests to a RESTCONF or ACI REST API and parse JSON responses?

  1. matplotlib
  2. numpy
  3. requests Correct answer.
  4. sqlite3

Explanation

The requests library provides simple HTTP methods and JSON decoding, making it a common choice for calling REST APIs. numpy and matplotlib are for numerical and plotting work, and sqlite3 handles embedded databases.

Question 8Data Center Automation and Programmability Fundamentals

Which Cisco SD-WAN component provides a centralized policy and orchestration plane and exposes APIs for automation?

  1. vSmart
  2. vBond
  3. vManage Correct answer.
  4. vEdge

Explanation

vManage is the management and orchestration plane that provides the GUI and REST API for configuration and monitoring. vEdge is the data plane device, vBond handles authentication and orchestration discovery, and vSmart distributes control plane policy.

Question 9Data Center Automation and Programmability Fundamentals

Which Cisco ACI object is used to apply a contract between two EPGs to permit specific traffic?

  1. A bridge domain subnet
  2. A VLAN pool
  3. A fabric membership policy
  4. A contract provided by one EPG and consumed by another Correct answer.

Explanation

In ACI, one EPG provides a contract and another EPG consumes it to allow the traffic defined by the contract's subjects and filters. Bridge domain subnets, fabric membership policies, and VLAN pools handle forwarding, membership, and VLAN allocation rather than inter-EPG permission.

Question 10Data Center Automation and Programmability Fundamentals

A Python script authenticates to the Cisco ACI REST API and needs to keep a session. Which approach best maintains authentication across multiple requests?

  1. Disable TLS verification to avoid authentication
  2. Use a requests.Session and include the APIC cookie in subsequent requests Correct answer.
  3. Re-authenticate with a new login for every single GET request
  4. Use HTTP instead of HTTPS to bypass the cookie

Explanation

The APIC login returns a token cookie that must be sent with later requests, and a requests.Session persists cookies and connection state automatically. Re-authenticating per request is inefficient, and disabling TLS or using HTTP weakens security without solving authentication.

Question 11Data Center Automation and Programmability Fundamentals

Which statement best describes the difference between imperative and declarative automation in data center networking?

  1. Declarative automation only works with SNMP
  2. Imperative automation specifies step-by-step commands, while declarative automation specifies the desired end state Correct answer.
  3. Imperative automation specifies the desired end state, while declarative automation lists CLI commands
  4. Both approaches require manual CLI entry on every device

Explanation

Imperative automation issues explicit ordered actions, whereas declarative automation describes the intended end state and lets the controller determine the steps. This distinction underpins intent-based controllers such as ACI and Nexus Dashboard.

Question 12Data Center Automation and Programmability Fundamentals

Which YANG statement is used to define a configuration node that can appear multiple times in a list?

  1. container
  2. list Correct answer.
  3. leaf-list
  4. leaf

Explanation

The YANG list statement defines a collection of entries that share a key and can repeat. A leaf is a single value, a container groups nodes without a value, and a leaf-list is a repeated leaf of the same type.

Question 13Data Center Automation and Programmability Fundamentals

A network engineer wants to retrieve only the interface configuration subtree from an NX-OS device using NETCONF. Which capability supports selecting a subtree?

  1. NTP authentication
  2. Syslog severity levels
  3. SNMP community strings
  4. NETCONF subtree filtering in the get or get-config operation Correct answer.

Explanation

NETCONF supports subtree filtering to return only the requested portion of the data tree. SNMP, syslog, and NTP are unrelated management or time services and do not filter NETCONF data.

Question 14Data Center Automation and Programmability Fundamentals

In Cisco ACI, what does the distinguished name (DN) of a managed object represent?

  1. The full hierarchical path of the object within the management information tree Correct answer.
  2. The IP address of the leaf switch hosting the endpoint
  3. The contract filter priority
  4. The VLAN ID assigned to the endpoint

Explanation

A DN uniquely identifies a managed object by its complete path in the management information tree, similar to a directory path. It is not a switch IP, a VLAN ID, or a filter priority.

Question 15Data Center Automation and Programmability Fundamentals

Which practice improves the security of a Python automation script that calls data center controller APIs?

  1. Embed the password directly in the script source
  2. Log the full authentication token at debug level
  3. Email the API token to team members
  4. Store credentials in environment variables or a secrets manager rather than hard-coding them Correct answer.

Explanation

Secrets should be kept out of source code and logs, using environment variables or a dedicated secrets manager. Hard-coding, emailing tokens, and logging tokens all expose credentials to unauthorized parties.

Question 16Data Center Automation and Programmability Fundamentals

Which Cisco ACI construct defines the Layer 3 default gateway for endpoints in an EPG?

  1. A bridge domain subnet configured as a gateway address Correct answer.
  2. A contract subject
  3. A VLAN pool
  4. An endpoint group contract

Explanation

The bridge domain subnet provides the default gateway address for endpoints associated with that bridge domain. Contracts govern communication, VLAN pools allocate VLANs, and EPG contracts are the same contract relationship rather than gateway addressing.

Question 17Data Center Automation and Programmability Fundamentals

A developer uses the Meraki Dashboard API and receives HTTP 429. What does this status indicate and how should the client respond?

  1. Authentication failed; the client should rotate the API key
  2. The request succeeded but returned no content
  3. The rate limit was exceeded; the client should back off and retry after the indicated interval Correct answer.
  4. The resource was not found; the client should create it

Explanation

HTTP 429 means too many requests were sent, and the client should honor the Retry-After interval and use exponential backoff. 404 indicates a missing resource, 401 indicates authentication failure, and 204 indicates success with no content.

Question 18Data Center Automation and Programmability Fundamentals

Which statement correctly describes the role of a device package or model in model-driven programmability for NX-OS?

  1. It supplies the YANG models that describe the device's configurable and operational data Correct answer.
  2. It defines the physical rack layout
  3. It encrypts all control plane traffic
  4. It replaces the need for any management interface

Explanation

Device packages provide the YANG models that define the schema for configuration and state data exposed over NETCONF and RESTCONF. They do not replace management interfaces, define rack layout, or encrypt traffic.

Question 19Data Center Automation and Programmability Fundamentals

Which Cisco platform exposes a REST API for managing UCS servers and is commonly used for infrastructure automation across compute?

  1. Cisco vManage
  2. Cisco Nexus Dashboard
  3. Cisco DNA Center
  4. Cisco Intersight Correct answer.

Explanation

Cisco Intersight is the cloud-operated management platform for UCS and other compute infrastructure with a REST API. Nexus Dashboard targets data center fabric, DNA Center targets campus networking, and vManage targets SD-WAN.

Question 20Data Center Automation and Programmability Fundamentals

An engineer needs to compare two versions of an ACI tenant configuration and roll back to a prior version. Which ACI capability supports this?

  1. Contract filters
  2. Endpoint learning
  3. Configuration snapshots and rollback Correct answer.
  4. VLAN pooling

Explanation

ACI supports configuration snapshots that can be compared and rolled back to restore prior tenant states. Endpoint learning, contract filters, and VLAN pooling are operational features unrelated to configuration versioning.

Question 21Data Center Automation and Programmability Fundamentals

In a CI/CD pipeline for network automation, what is the primary benefit of validating intended configuration against a YANG model before deployment?

  1. It catches schema and type errors before changes reach production devices Correct answer.
  2. It guarantees zero packet loss during deployment
  3. It removes the need for authentication
  4. It automatically rewrites device firmware

Explanation

Model validation checks that the configuration conforms to the expected schema and data types, catching errors early in the pipeline. It cannot guarantee zero packet loss, replace authentication, or upgrade firmware.

Question 22Data Center Automation and Programmability Fundamentals

A team wants idempotent configuration of NX-OS interfaces through automation. Which approach best achieves idempotency?

  1. Send the full interface configuration on every run regardless of current state
  2. Declare the desired interface state and let the tool reconcile only differences Correct answer.
  3. Reboot switches before each configuration push
  4. Rely on manual CLI entry before each run

Explanation

Idempotency means repeated runs converge to the same declared state and change only what differs. Blindly resending full configuration or rebooting does not reconcile state and may cause disruption, and manual entry defeats automation.

Question 23Data Center Automation and Programmability Fundamentals

Which consideration is most important when choosing between synchronous and asynchronous API calls for a large-scale fabric provisioning script?

  1. Whether the script uses tabs or spaces
  2. Whether the device hostname is uppercase
  3. Whether the controller returns a task identifier that must be polled for completion Correct answer.
  4. Whether syslog is enabled on the switch

Explanation

Many controller operations are long-running and return a task or job identifier that must be polled, so the script must handle asynchronous completion correctly. Formatting, hostname case, and syslog settings do not determine the API call pattern.

Question 24Data Center Automation and Programmability Fundamentals

An ACI contract is provided by EPG-A and consumed by EPG-B, but traffic still fails. Which analysis is most consistent with ACI policy behavior?

  1. The VLAN pool must be larger than 1000 IDs
  2. The bridge domain must always be deleted and recreated
  3. The contract filter may not match the required ports or protocol, or the EPGs may not be in the same VRF Correct answer.
  4. The fabric must be rebooted to apply contracts

Explanation

Contract enforcement depends on matching filters and on the EPGs being in VRFs that permit the communication path. Deleting bridge domains, resizing VLAN pools, or rebooting the fabric are not standard remedies for a filter or VRF mismatch.

Question 25Data Center Automation and Programmability Fundamentals

Why is using a controller-level API generally preferred over per-device CLI scripting for large data center fabrics?

  1. The controller maintains fabric-wide state and policy consistency that per-device scripts may violate Correct answer.
  2. CLI scripting cannot change interface settings
  3. Controllers remove the need for network design
  4. Controllers eliminate the need for any device credentials

Explanation

Controller APIs operate on a fabric-wide model, preserving policy consistency and intent, whereas per-device scripts can drift and create inconsistent state. Controllers still require credentials, CLI scripting can change interfaces, and network design remains necessary.

Question 26Data Center Automation and Programmability Fundamentals

Which Cisco ACI object type is the root of the tenant configuration hierarchy and contains all other tenant-level managed objects?

  1. fvAEPg
  2. fvBD
  3. fvTenant Correct answer.
  4. fvCtx

Explanation

The fvTenant class is the container object that holds every other tenant-scoped managed object, such as VRFs, bridge domains, and EPGs. Its distinguished name is typically uni/tn-<name>, making it the anchor for tenant configuration.

Question 27Data Center Automation and Programmability Fundamentals

In Cisco ACI, which managed object holds the fabric-wide access policies such as VLAN pools, interface policies, and switch profiles?

  1. uni/infra
  2. uni/vmmp
  3. uni/tn-infra
  4. uni/fabric Correct answer.

Explanation

Fabric-wide access and infrastructure policies live under the fabric container, addressed as uni/fabric. VLAN pools, physical domain profiles, and related access constructs are organized there rather than inside a tenant.

Question 28Data Center Automation and Programmability Fundamentals

Which HTTP methods does the Cisco ACI REST API use to create, read, update, and delete managed objects?

  1. POST for create, GET for read, DELETE for update, PUT for delete
  2. POST for create, GET for read, POST for update, DELETE for delete Correct answer.
  3. GET for create, PUT for read, PATCH for update, DELETE for delete
  4. PUT for create, GET for read, POST for update, PATCH for delete

Explanation

The ACI REST API follows REST conventions: POST creates objects, GET reads them, POST to an existing object updates its attributes, and DELETE removes them. A GET with a query filter can also read a subtree or class of objects.

Question 29Data Center Automation and Programmability Fundamentals

Which encoding format does the Cisco ACI REST API use for request and response payloads by default?

  1. JSON Correct answer.
  2. YAML
  3. Protocol Buffers
  4. XML

Explanation

ACI REST responses are JSON by default, and payloads are JSON structures that mirror the managed object tree. Clients can request XML with an Accept header, but JSON is the default and most common format.

Question 30Data Center Automation and Programmability Fundamentals

Which Cisco SD-WAN component is responsible for the data plane, forwarding traffic between sites over the overlay?

  1. vManage
  2. vEdge or cEdge router Correct answer.
  3. vBond
  4. vSmart

Explanation

The vEdge or cEdge router is the data-plane device that forwards traffic and establishes IPsec tunnels across the SD-WAN overlay. vManage, vSmart, and vBond provide management, control, and orchestration functions respectively.

Question 31Data Center Automation and Programmability Fundamentals

Which protocol does Cisco SD-WAN use to distribute routing and policy information from vSmart controllers to edge devices?

  1. NETCONF
  2. BGP
  3. OSPF
  4. OMP Correct answer.

Explanation

Overlay Management Protocol (OMP) is Cisco SD-WAN's proprietary control protocol. vSmart controllers use OMP to send routes, TLOCs, and policies to the edges over the DTLS control connections.

Question 32Data Center Automation and Programmability Fundamentals

Which Cisco platform provides a REST API for managing UCS servers and is commonly used for infrastructure automation across a UCS domain?

  1. UCS Manager Correct answer.
  2. NX-OS
  3. ACI
  4. Intersight

Explanation

Cisco UCS Manager exposes a REST API that lets automation tools manage servers, service profiles, and policies within a UCS domain. Intersight is a separate cloud-based management platform with its own API, not the on-premises UCS domain manager.

Question 33Data Center Automation and Programmability Fundamentals

A developer needs to send a JSON payload to an ACI controller to create a new bridge domain. Which HTTP request best accomplishes this?

  1. GET /api/mo/uni/tn-Prod/BD-Web.json
  2. POST /api/mo/uni/tn-Prod/BD-Web.json with the fvBD payload Correct answer.
  3. GET /api/class/fvBD.json
  4. DELETE /api/mo/uni/tn-Prod/BD-Web.json

Explanation

Creating a managed object uses a POST to its distinguished name URL with a JSON body describing the object. The DN in the URL identifies the parent and object name, and the payload supplies attributes.

Question 34Data Center Automation and Programmability Fundamentals

A Python script must retrieve all EPGs in a tenant named Prod without knowing their names in advance. Which ACI REST request is most appropriate?

  1. GET /api/mo/uni/tn-Prod.json?query-target=subtree Correct answer.
  2. POST /api/mo/uni/tn-Prod.json
  3. GET /api/mo/uni/tn-Prod/out-Default.json
  4. GET /api/class/fvAEPg.json?query-target-filter=eq(fvAEPg.name,"Prod")

Explanation

A subtree query on the tenant DN returns all descendant managed objects, which can be filtered to the fvAEPg class. This discovers EPGs without prior knowledge of their names.

Question 35Data Center Automation and Programmability Fundamentals

Which ACI object must be associated with an EPG so that its endpoints can receive an IP address from a subnet defined on a bridge domain?

  1. A domain profile
  2. A contract
  3. A bridge domain association Correct answer.
  4. A VRF

Explanation

An EPG must be associated with a bridge domain for its endpoints to use the BD's subnets and default gateway. The EPG-to-BD relationship is what ties application endpoints to Layer 3 services.

Question 36Data Center Automation and Programmability Fundamentals

An engineer wants to assign a VLAN pool to a physical domain in ACI so that EPG static paths can use those VLANs. Which object relationship is required?

  1. Associate the VLAN pool with the contract
  2. Associate the VLAN pool with the VRF
  3. Associate the VLAN pool directly with the tenant
  4. Associate the VLAN pool with the physical domain, and associate the domain with the EPG Correct answer.

Explanation

VLAN pools are attached to domains, and EPGs are bound to domains through domain profiles. This chain lets the fabric allocate VLANs for static paths on leaf interfaces.

Question 37Data Center Automation and Programmability Fundamentals

Which Cisco SD-WAN API endpoint family is used to retrieve device inventory information from vManage?

  1. /dataservice/template/feature
  2. /dataservice/policy/definition
  3. /dataservice/device Correct answer.
  4. /dataservice/tenant

Explanation

The /dataservice/device family of endpoints exposes device inventory and status information from vManage. Templates and policies are managed under separate endpoint families.

Question 38Data Center Automation and Programmability Fundamentals

A developer authenticates to the Cisco SD-WAN vManage API and receives a session token. How should the token be used on subsequent requests?

  1. In the X-XSRF-TOKEN header
  2. In the request body of every call
  3. In the Authorization header as a Bearer token Correct answer.
  4. As a query parameter named token

Explanation

vManage returns a session token that clients present in the Authorization header using the Bearer scheme. This authenticates subsequent API calls without resending credentials.

Question 39Data Center Automation and Programmability Fundamentals

Which Cisco Intersight API feature lets a client retrieve only selected fields from a resource to reduce payload size?

  1. The $count parameter
  2. The $select query parameter Correct answer.
  3. The $apply parameter
  4. The $expand parameter

Explanation

Intersight supports OData-style query options, and $select limits the response to specified properties. This reduces payload size and improves efficiency when only a few fields are needed.

Question 40Data Center Automation and Programmability Fundamentals

Which data model and encoding does Cisco NX-OS use to expose configuration and operational state through NETCONF?

  1. YANG models with XML encoding over SSH Correct answer.
  2. CLI scraping with screen-scraping libraries
  3. SNMP MIBs with BER encoding
  4. RESTCONF with JSON only

Explanation

NX-OS NETCONF uses YANG data models and XML encoding over an SSH transport. This enables model-driven configuration and retrieval of operational data.

Question 41Data Center Automation and Programmability Fundamentals

A developer wants to make a Python automation script idempotent when configuring NX-OS interfaces. Which approach best achieves this?

  1. Read the current interface state, compare it to the desired state, and apply only the differences Correct answer.
  2. Run the same CLI commands every time regardless of current state
  3. Use a random delay before each command
  4. Delete and recreate all interfaces on every run

Explanation

Idempotency means repeated runs converge to the same desired state without side effects. Reading current state and applying only necessary changes avoids unnecessary reconfiguration and errors.

Question 42Data Center Automation and Programmability Fundamentals

A network engineer needs to compare two versions of an ACI tenant configuration and roll back to a prior version. Which ACI capability best supports this?

  1. Contracts
  2. Snapshots and rollback Correct answer.
  3. Configuration zones
  4. Service graphs

Explanation

ACI snapshots capture tenant configuration at a point in time and support comparison and rollback. This is the built-in mechanism for configuration versioning and recovery.

Question 43Data Center Automation and Programmability Fundamentals

Which consideration is most important when choosing between synchronous and asynchronous API calls for a large-scale fabric automation task?

  1. Synchronous calls cannot use HTTPS.
  2. Asynchronous calls eliminate the need for error handling.
  3. Synchronous calls are always faster than asynchronous calls.
  4. Asynchronous calls can improve throughput by overlapping I/O wait times. Correct answer.

Explanation

Asynchronous calls allow a client to issue multiple requests without blocking on each response, improving throughput when network latency dominates. Error handling is still required, and synchronous calls can also use HTTPS.

Question 44Data Center Automation and Programmability Fundamentals

An ACI contract is provided by EPG-A and consumed by EPG-B, but traffic still fails. Which analysis is most consistent with ACI contract behavior?

  1. The contract must define subjects with filters that match the traffic, and the provider and consumer relationships must be correctly applied. Correct answer.
  2. The contract must be applied as a provider contract on EPG-B as well.
  3. The contract must be applied as a consumer contract on EPG-A as well.
  4. The EPGs must be in the same bridge domain for the contract to work.

Explanation

Contracts require subjects containing filters that match the traffic, and the provider and consumer relationships must be correctly applied to the EPGs. A contract without matching filters or with mismatched relationships will not permit traffic.

Question 45Data Center Automation and Programmability Fundamentals

A developer needs to retrieve a large number of ACI objects and wants to minimize the risk of incomplete results. Which approach is most appropriate?

  1. Request the entire class without filters and ignore the response size
  2. Rely on the default page size and assume all objects are returned
  3. Use a single GET with a timeout of one second
  4. Use pagination parameters such as page and page-size to retrieve results in batches Correct answer.

Explanation

ACI REST APIs support pagination, and using page and page-size parameters ensures all objects are retrieved in manageable batches. Ignoring pagination can lead to incomplete results or timeouts.

Question 46Data Center Automation and Programmability Fundamentals

An engineer is designing a Python library that wraps multiple Cisco APIs, including ACI, SD-WAN, and Intersight. Which design choice best supports maintainability?

  1. Hard-code credentials in each module
  2. Use a shared HTTP session with configurable authentication per platform Correct answer.
  3. Avoid using exceptions and return None on errors
  4. Write separate copies of request logic for each API

Explanation

A shared HTTP session with pluggable authentication lets each platform use its own auth scheme while reusing connection pooling and request logic. This improves maintainability and consistency.

Question 47Data Center Automation and Programmability Fundamentals

A team wants to validate ACI tenant configuration changes in a CI pipeline before applying them to production. Which approach best fits ACI's operational model?

  1. Run changes only during business hours
  2. Disable contracts during validation to avoid failures
  3. Apply changes directly to production and rely on manual review afterward
  4. Use configuration zones to validate changes against a snapshot before deployment Correct answer.

Explanation

ACI configuration zones compare proposed changes against a snapshot and can validate them before deployment. This supports pre-change validation in a CI pipeline.

Question 48Data Center Automation and Programmability Fundamentals

Which statement best describes how Cisco SD-WAN policies are applied through the vManage API?

  1. Policies are applied only through the vManage GUI
  2. Policies are defined centrally and pushed to vSmart controllers, which distribute them to edges Correct answer.
  3. Policies are applied directly to each edge device via CLI
  4. Policies are stored only in vBond and never distributed

Explanation

SD-WAN policies are defined centrally in vManage and activated on vSmart controllers, which then distribute them to edge devices via OMP. This centralizes policy management across the fabric.

Question 49Data Center Automation and Programmability Fundamentals

In a Cisco ACI fabric, a developer is writing a script that must log in to the APIC REST API and obtain a session token before making further calls. Which APIC endpoint and method combination is used for this authentication step?

  1. PUT to /api/mo/uni/userext/user-admin.json with the credentials in the request body
  2. GET to /api/aaaLogin.json with the credentials supplied as query string parameters
  3. POST to /api/aaaLogin.json with a payload containing the user name and password attributes Correct answer.
  4. POST to /api/class/aaaUser.json with the credentials stored in a cookie header

Explanation

The APIC exposes a dedicated login resource at /api/aaaLogin.json; a POST carrying the aaaUser attributes name and pwd returns a token in the imdata payload, which the client then sends as an APIC-Cookie. Login is a state-changing action, so POST is required rather than GET or PUT. The token can later be refreshed through aaaRefresh and terminated through aaaLogout.

Question 50Data Center Automation and Programmability Fundamentals

A developer is building a tool that must create, modify, and delete tenant objects on an APIC through REST calls. The tool needs a single request form that works for all three operations without changing URL structure. Which ACI REST approach satisfies this requirement?

  1. Issue a POST to /api/mo/uni/tn-<name>.json with the desired object state; the APIC creates or updates the object as needed Correct answer.
  2. Issue a GET with an imdata filter to create objects and a DELETE to remove them
  3. Issue a POST to create, a PUT to modify, and a DELETE to remove, each against a different class-based URL
  4. Issue a PATCH to /api/node/mo/uni.json for every operation and rely on the payload to indicate intent

Explanation

ACI's managed object model treats a POST to an MO URL as a declarative statement of desired state: if the object does not exist it is created, and if it exists the supplied attributes are applied. Deletion is the exception in that it requires a status attribute of deleted in the payload, but the same MO endpoint and POST method are still used. This uniform pattern is what allows generic tooling to configure any class without per-operation URL logic.