Cisco 350-901 DEVCOR/AUTOCOR flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

Twelve-Factor config

Configuration that varies between deployments is stored in environment variables rather than code, so the same build artifact can run unchanged in dev, test, and production.

Semantic Versioning

Version numbers use MAJOR.MINOR.PATCH: MAJOR for incompatible changes, MINOR for backward-compatible features, PATCH for backward-compatible fixes. Pre-release and build metadata are appended after a hyphen or plus sign.

Idempotent HTTP methods

GET, PUT, DELETE, and HEAD are idempotent: repeating an identical request yields the same server state. POST is not idempotent, so retried POSTs need a deduplication key.

Test pyramid

A testing strategy with many fast unit tests at the base, fewer integration tests in the middle, and few slow end-to-end tests at the top, balancing feedback speed against confidence.

Git rebase versus merge

Rebase replays commits onto a new base, producing linear history but new commit hashes; merge preserves history and creates a commit with two parents. Avoid rebasing shared branches.

Singleton pattern

A design pattern that restricts a class to one instance and provides a global access point, commonly used for configuration or connection managers; it complicates testing and parallelism.

Statelessness in REST

Each API request must contain all information needed to process it; the server stores no client session context between requests, which improves scalability and simplifies failure recovery.

HTTP 429 response

Too Many Requests indicates rate limiting. The response typically includes Retry-After, and clients should back off exponentially with jitter rather than retrying immediately.

OAuth client credentials flow

A machine-to-machine OAuth 2.0 grant where the client sends its ID and secret directly to the token endpoint and receives an access token without any user interaction or redirect.

Cursor pagination

The API returns an opaque token pointing to the next page instead of a numeric offset, keeping results stable when records are inserted or deleted during iteration.

Conditional GET with ETag

A client resends an ETag in If-None-Match; if the resource is unchanged the server returns 304 Not Modified with no body, saving bandwidth on repeated reads.

Webhook signature verification

The receiver recomputes an HMAC over the raw request body using a shared secret and compares it to the signature header, rejecting forged deliveries before processing.

Bearer token placement

Access tokens are sent in the Authorization header as 'Bearer <token>'. Placing tokens in URLs leaks them into logs, proxies, and browser history.

DNA Center auth token

POST credentials via HTTP Basic to /dna/system/api/v1/auth/token; the returned X-Auth-Token header value authenticates subsequent Intent API calls until it expires.

Meraki API key header

Meraki dashboard API requests include the X-Cisco-Meraki-API-Key header and target https://api.meraki.com/api/v1 with organization-scoped resource paths.

Intersight signed requests

Cisco Intersight authenticates REST calls with an HMAC signature built from a key ID, secret, request target, and date, or with an OAuth bearer token.

Webex webhooks

A Webex integration registers a target URL; when a subscribed event occurs, Webex POSTs a JSON payload describing the resource and event to that URL.

APIC object model

Cisco ACI's APIC exposes managed objects as classes such as fvTenant and fvBD, queried over HTTPS with filters and authenticated by a login token cookie.

NETCONF operations

NETCONF runs over SSH and uses XML operations including get-config, edit-config, lock, commit, and validate, operating on YANG-modeled configuration and state datastores.

RESTCONF mapping

RESTCONF exposes YANG-modeled data over HTTP using GET, POST, PUT, PATCH, and DELETE with JSON or XML encoding, typically under a /restconf/data base path.

vManage API header

Cisco SD-WAN vManage requires a session obtained via j_security_check, after which requests to /dataservice paths include the X-XSRF-TOKEN header.

Containers versus virtual machines

Containers share the host kernel and isolate with namespaces and cgroups, giving small fast images; VMs run full guest operating systems with stronger isolation boundaries.

Kubernetes Deployment object

A Deployment manages a ReplicaSet of Pods, declares desired replica count, and performs rolling updates and rollbacks by changing the Pod template.

OIDC ID token

OpenID Connect adds authentication to OAuth 2.0 by issuing a signed JWT ID token containing subject, issuer, audience, and expiry claims that the client validates.

JWT structure

A JSON Web Token is three Base64URL parts separated by dots: header, payload, and signature. The payload is encoded, not encrypted, so it must not hold secrets.

Broken object-level authorization

An API flaw where a user can access another user's object by changing an identifier in the request; defenses enforce ownership checks on every object access.

Blue-green deployment

Two identical environments run side by side; traffic switches from the live blue environment to the new green one after validation, enabling fast rollback by switching back.

Ansible idempotency

Ansible modules describe desired state, so running a playbook repeatedly produces the same result and reports changed only when an actual modification occurs.

Terraform state locking

Terraform stores resource mappings in a state file; a remote backend with locking prevents two concurrent applies from corrupting that state.

Terraform plan and apply

Plan compares configuration, state, and real infrastructure to show pending changes; apply executes that plan, creating, updating, or destroying resources to match the declaration.

GitOps reconciliation

Git holds the declared desired state; an in-cluster agent continuously compares live resources to the repository and reconciles drift, with rollback performed by reverting commits.

gNMI streaming telemetry

A gRPC-based protocol that pushes structured, model-driven operational data from network devices on a subscription, replacing periodic SNMP polling with near-real-time updates.