Practice & Reference · Glossary

Glossary

Every bit of migration jargon in one place, in plain language — 199 terms, from “rehost” and “landing zone” to “data gravity” and “egress.” Search to jump straight to a word.

☺ Explain it like I’m 10

This is the mover’s dictionary. If a word in any lesson ever looks scary, it’s explained here in one friendly sentence. Nutty the Squirrel keeps the whole list neatly filed.

🐿️Your host for this topic: Nutty the Squirrel — the Academy’s cataloguer, who files every term by meaning so you can find it fast.

12-Factor AppA methodology of twelve principles (by Adam Wiggins of Heroku, ~2011) for building portable, scalable, cloud-friendly applications.

7 RsThe seven strategies for migrating an application to the cloud: Retire, Retain, Rehost, Relocate, Repurchase, Replatform, and Refactor (Re-architect).

AgilityHow quickly a team can build, change, and ship software. A major cloud driver because managed services remove undifferentiated setup work.

Anti-patternA common approach that looks like a good solution but reliably produces bad outcomes; the opposite of a best practice.

API (Application Programming Interface)A defined contract that lets software components request services from one another in a predictable way.

API-first designAn approach in which the API contract (e.g., OpenAPI/REST or GraphQL) is designed and agreed before implementation, enabling parallel work and reusable interfaces.

ApplicationA program that performs work for users (e.g., a website, an accounting system). In this course, the 'family and pets.'

AutoscalingThe automatic adding or removing of computing resources in response to real-time demand, so an application has enough capacity during peaks and saves money during lulls.

Availability Zone (AZ)One or more discrete, isolated data centers within a region, each with independent power, cooling, and networking, so a failure in one does not take down the others.

AWS Application Migration Service (MGN) / AWS Transform MGNAWS's rehosting service that replicates whole servers into EC2 with minimal downtime; successor to CloudEndure Migration, rebranded AWS Transform MGN in June 2026.

AWS Cloud Adoption Framework (CAF)AWS's readiness framework organized into six perspectives: Business, People, Governance, Platform, Security, and Operations.

AWS CloudFormationAWS's native IaC service that provisions AWS resources from JSON or YAML templates.

AWS DMS (Database Migration Service)A managed AWS service that migrates database data, supporting online (continuous) replication for near-zero-downtime cutovers.

AWS Migration Acceleration Program (MAP)AWS's incentive-backed program for executing migrations in three phases: Assess, Mobilize, and Migrate & Modernize.

AWS Snow FamilyAWS's line of physical data-transfer appliances (e.g., Snowball); largely being retired, with new customers directed to online transfer, the AWS Data Transfer Terminal, or partners.

AWS Well-Architected FrameworkAWS's set of best practices organized into six pillars: operational excellence, security, reliability, performance efficiency, cost optimization, and sustainability.

Azure BicepMicrosoft's Azure-specific IaC language with a concise syntax that compiles to ARM templates; relies on Azure Resource Manager for state.

Azure Cloud Adoption Framework (CAF)Microsoft's framework with seven methodologies: Strategy, Plan, Ready, Adopt, Govern, Secure, and Manage.

Backup and restore (DR strategy)The cheapest disaster-recovery approach: keep backups in the cloud and rebuild/restore after an outage. Highest RTO/RPO (hours), lowest cost.

Big bangA migration or deployment approach that moves everything to the new environment in a single, all-at-once cutover — fast but risky, and exactly the reckless one-night move Gizmo the Gremlin loves.

Big-bang cutoverSwitching everything from the old environment to the new one in a single, all-at-once event rather than in phases.

Bill shockAn unexpectedly large cloud invoice caused by unmonitored, over-provisioned, or idle resources.

Blast radiusHow much of the system or how many users are affected when something goes wrong.

Block storageStorage that presents raw volumes attached to a single server (e.g., Amazon EBS, Azure managed disks) — used for operating-system disks and database volumes needing low latency.

Blue-green deploymentA release technique that runs two identical environments — 'blue' (current) and 'green' (new) — and switches all traffic from one to the other at once, allowing an instant rollback if problems appear.

Boiling the oceanAttempting to tackle far too much scope at once instead of prioritizing a manageable slice.

BrownfieldWorking within an existing environment — migrating or modernizing legacy systems while respecting their current constraints and dependencies.

Bulk load (full load)A one-time copy of all existing data from source to target.

Business caseThe financial and strategic justification that compares current TCO against projected cloud cost and benefits to justify the migration.

CAF (Cloud Adoption Framework)The AWS Cloud Adoption Framework: a set of best practices organized into six perspectives — Business, People, Governance, Platform, Security, and Operations — that guide an organization's overall cloud transformation (Microsoft and Google publish their own equivalents).

Canary deploymentA release technique that sends a change to a small subset of users or servers first and monitors it before gradually rolling it out to everyone, so problems are caught early with limited blast radius.

CDC (Change Data Capture)A technique that continuously tracks and replicates changes made to a source database so the target stays in sync during a migration, keeping downtime to a minimum.

Change Data Capture (CDC)Reading a database's transaction log to stream each row-level change to another system in near real time.

Change managementThe structured approach to preparing and supporting people (training, communication, new skills) through the organizational change a migration brings.

CI/CDContinuous Integration (automatically building and testing every change) and Continuous Delivery/Deployment (automatically releasing validated changes), the automation engine of DevOps.

CIDR / subnetCIDR is the notation (e.g., 10.0.0.0/16) for defining IP address ranges; a subnet is a subdivision of a network's address range, typically split into public (internet-reachable) and private (internal-only) subnets inside a VPC.

CloudComputing resources (servers, storage, databases, services) rented over the internet from a provider such as AWS, Microsoft Azure, or Google Cloud. In this course, Cloudville / Sky City.

Cloud Center of Excellence (CCoE)A cross-functional team that defines cloud standards, guardrails, reusable patterns (like landing zones), and best practices, accelerating and governing an organization's migration and cloud operations.

Cloud migrationThe process of moving applications, data, and workloads from one environment (often an on-premises data center) to a cloud provider such as AWS, Azure, or Google Cloud.

Cloud repatriationAlso called reverse migration: moving workloads or data back from public cloud to private cloud or on-premises, typically for cost, performance, control, or compliance reasons.

Cloud-nativeBuilt specifically to exploit cloud features like elastic scaling, managed services, and serverless — the destination of a Refactor.

Cloud-to-cloud migrationMoving workloads and data from one cloud provider to another (e.g., AWS to Azure or Google Cloud).

CloudEndure MigrationThe earlier AWS rehosting product (acquired by AWS in 2019) whose technology became AWS Application Migration Service / MGN.

CNCF (Cloud Native Computing Foundation)A Linux Foundation body that hosts and governs cloud-native open-source projects; Kubernetes was its first hosted and first graduated project.

ContainerA lightweight, portable package containing an application plus its dependencies that shares the host OS kernel and runs consistently across environments; Docker is the leading tool.

Continuous replicationOngoing copying of changes from source to target after the initial load, keeping the two in sync until cutover.

CutoverThe moment the live workload switches from the old environment to the new one. The riskiest instant of a move, which is why big-bang cutovers are discouraged.

Cutover windowThe agreed time slot (often a night or weekend) in which a wave’s final data sync, switch-over, validation — and, if needed, rollback — must all fit.

Data / databaseThe information an organization stores and the systems that organize it (e.g., customer records). In this course, the 'boxes.'

Data centerA building full of computer servers, storage, and networking that runs an organization's applications and stores its data.

Data gravityA concept (coined by Dave McCrory, 2010) that large datasets attract applications, services, and more data toward them and become harder to move as they grow.

Data lakeA repository that stores massive volumes of raw data in its native format, applying structure only when data is read (schema-on-read); ideal for analytics and machine learning.

Data migrationThe process of moving data (database records, files, backups) from one storage system or location to another, as opposed to moving the applications or servers that use it.

Data residency / data sovereigntyRules requiring that data physically reside in, or be governed by the laws of, a specific country or region (e.g., under GDPR or DORA).

Data sovereigntyThe principle that data is subject to the laws of the country where it is physically stored; stricter than data residency because it concerns legal jurisdiction, not just location.

Data validation and reconciliationProving migrated data is complete and correct by comparing source and target using row counts, checksums/hashes, referential-integrity checks, and sample records.

Data warehouseA store of cleaned, structured data with a schema applied on write (schema-on-write), optimized for business intelligence and reporting.

DecommissionTo formally shut down, remove, and dispose of a system or server once it is no longer needed — the final step when retiring an application.

DecommissioningSafely shutting down and retiring the old on-premises environment — performed last, only after the new system is proven stable.

Dedicated interconnectA private physical network link that bypasses the public internet (AWS Direct Connect, Azure ExpressRoute, Google Cloud Interconnect).

Dependency mappingDocumenting which systems connect to and rely on which others, so nothing is moved in isolation and broken.

DevOpsA culture and set of practices that unite development and operations through automation and collaboration to deliver software faster and more reliably.

Disaster recovery (DR)The set of policies, tools, and procedures for restoring IT systems and data after a major disruptive event such as an outage, cyberattack, or natural disaster.

DiscoveryTaking a complete inventory of existing servers, applications, and data before planning the move.

Discovery & assessmentThe phase and tooling that inventory existing servers, applications, and dependencies and estimate cloud cost and readiness before migrating.

Distributed monolithAn anti-pattern where a system is split into services that remain so coupled they must be deployed together — distributed cost with no independence benefit.

DMS (Database Migration Service)A managed tool — such as AWS Database Migration Service — that moves databases to the cloud, often with minimal downtime, and can convert between different database engines.

DockerThe platform (released 2013) that popularized containerization by making it easy to build, share, and run application containers.

DowntimeA period when a service is unavailable to users, often a risk during a migration cutover; good plans minimize it with phased moves and rollback options.

Dual-writeApplication logic that writes every change to two data stores (old and new) at the same time.

Egress costThe fee cloud providers charge for data leaving their network (e.g., cloud-to-on-premises).

Egress feesPer-gigabyte charges a cloud provider bills for transferring data OUT of its cloud to the internet or another provider; inbound (ingress) is usually free.

ElasticityThe ability to automatically grow AND shrink resources to match demand, so you pay for roughly what you use instead of provisioning for peak load.

ETL / ELTExtract-Transform-Load (reshape data before loading) / Extract-Load-Transform (load raw data, then transform inside a powerful target such as a cloud data warehouse).

Event-driven architectureA design where services communicate by producing and reacting to events (messages about things that happened), keeping producers and consumers loosely coupled.

FaaS (Function as a Service)A cloud model that runs small, single-purpose pieces of code on demand in response to events, with the provider automatically managing servers and scaling — AWS Lambda is a leading example.

Facade (routing layer)A component placed in front of a system that receives all requests and decides where to send them — the key enabler of the Strangler Fig pattern.

Feature flag (toggle)A switch in the code that turns a feature or code path on or off without redeploying — often used with Branch by Abstraction and Canary.

File storageShared network file systems accessible by many servers at once (e.g., Amazon EFS, Azure Files, Google Filestore), useful for lift-and-shift apps that expect a traditional file share.

FinOpsA cultural practice and framework (finance + engineering + business) for managing cloud cost, with phases Inform, Optimize, and Operate; stewarded by the FinOps Foundation.

FrameworkA structured playbook of best practices from a vendor (e.g., AWS CAF, Azure CAF) that guides how to plan and run a migration.

Functions-as-a-Service (FaaS)A serverless category that runs individual functions in response to events; examples include AWS Lambda, Azure Functions, and Google Cloud Functions.

GDPRThe EU General Data Protection Regulation, which governs how personal data of EU residents is stored, processed, and transferred — a common driver of data-residency and region choices in migrations.

Google Cloud migration pathGoogle's four-phase move: Assess, Plan, Deploy, and Optimize.

GovernanceThe policies and guardrails that keep a cloud environment secure, compliant, and cost-controlled by default.

GreenfieldBuilding a brand-new system from scratch in a fresh environment, free of constraints from existing legacy systems.

GuardrailsAutomated policies that prevent or flag risky, non-compliant, or costly actions in a cloud environment.

Heterogeneous migrationA database migration where source and target use different engines (e.g., Oracle to PostgreSQL), requiring schema conversion.

High availability (HA)Designing a system to keep running through component failures, typically by spreading redundant resources across multiple Availability Zones so one failure does not cause an outage.

HIPAAA US law setting privacy and security rules for protected health information; workloads handling health data must meet its safeguards, influencing which services and regions can be used.

Homogeneous migrationA database migration where source and target use the same engine (e.g., MySQL to MySQL), regardless of version.

Hybrid cloudAn environment combining private/on-premises infrastructure with public cloud, connected and managed as a single system.

Hybrid interconnectPrivate, high-speed links (e.g., AWS Direct Connect, Azure ExpressRoute, Google Cloud Interconnect, or VPN) that join on-premises and cloud into one network.

HypercareThe intense, closely-monitored support period immediately after cutover to detect and fix issues quickly.

HyperscalerA very large public cloud provider that operates data centers at massive scale — namely AWS, Microsoft Azure, and Google Cloud.

HypervisorThe software layer that creates and runs virtual machines. Relocate moves workloads at this layer without touching the app.

IaaS (Infrastructure as a Service)Renting raw cloud building blocks (virtual servers, storage, networking) while you manage the operating system and everything above it.

IAM (Identity and Access Management)The system that controls who (users/services) can access which cloud resources and what they can do.

Infrastructure as Code (IaC)Defining and provisioning infrastructure through declarative, version-controlled text files instead of manual configuration; tools include Terraform, CloudFormation, and Bicep.

IngressData transferred INTO a cloud, which providers typically do not charge for.

IT migrationThe planned process of moving applications, data, VMs, and workloads from one computing environment to another while keeping them functioning.

Kubernetes (EKS / AKS / GKE)An orchestrator that runs and scales fleets of containers automatically; offered managed as Amazon EKS, Azure AKS, and Google GKE.

Kubernetes (K8s)An open-source container orchestration system that automates deploying, scaling, and healing containers across a cluster; created by Google (2014, based on Borg) and donated to the CNCF (2015).

Landing zoneA pre-configured, secure, governed cloud foundation (identity, networking, security guardrails) set up before any workloads are migrated in.

Legacy systemOlder software that still works and still matters but is difficult to change or maintain (in this course, nervous Iggy the Iron Server).

Lift-and-shiftThe everyday nickname for the Rehost strategy: moving a workload to the cloud unchanged and quickly, without redesigning it.

Load balancerA component that distributes incoming traffic across multiple servers to improve availability and scale, and a key enabler of rolling, blue-green, and canary deployments.

Managed databaseA database run and maintained by the cloud provider (e.g., Amazon RDS, Azure SQL Database, Google Cloud SQL), removing most operational chores from your team.

Managed serviceA cloud service the provider operates for you (e.g., a managed database), so you consume it without patching, backing up, or running the underlying servers yourself.

MAP (Migration Acceleration Program)AWS's structured program of tools, best practices, expert guidance, and funding that helps organizations migrate through three phases — Assess, Mobilize, and Migrate & Modernize.

Message queueA service that stores and forwards messages between decoupled components (e.g., Amazon SQS, Azure Service Bus, Google Pub/Sub), enabling asynchronous, resilient communication.

MicroservicesAn architecture that splits an application into many small, independent services that can be built, deployed, and scaled separately.

MigrationMoving an application or workload from one environment to another (e.g., on-premises to cloud), typically with little or no change to the application itself.

Migration factoryRunning migration waves as a repeatable production line — shared tooling, runbooks, and per-wave retrospectives make each wave faster and cheaper than the last.

Migration lifecycleThe full, staged journey of moving IT to the cloud, commonly modeled as Assess → Mobilize → Migrate & Modernize → Operate/Optimize.

Migration waveA batch of related workloads migrated together in a single iteration; large migrations are split into successive waves to reduce risk and complexity.

ModernizationImproving a workload as or after you move it — for example replatforming or refactoring it to use cloud-native services.

MonolithA single, large, tightly-coupled application where all functions are bundled together — often the thing a Refactor breaks apart.

Multi-cloudUsing two or more public cloud providers (e.g. AWS, Azure, and Google Cloud) at the same time, often for resilience, flexibility, or best-of-breed services. Also spelled "multicloud."

Multi-site / active-active (DR strategy)Running full production capacity in more than one location simultaneously so failover is near-instant — the lowest RTO/RPO and the most expensive DR strategy.

Object storageStorage that keeps data as objects accessed over HTTP APIs (e.g., Amazon S3, Azure Blob, Google Cloud Storage); highly scalable and cheap, ideal for files, backups, media, and data lakes.

Observability / monitoringThe ability to understand a system's internal state from its outputs — typically logs, metrics, and traces — so problems can be detected and diagnosed quickly.

Offline data transferShipping bulk data on a rugged, encrypted physical appliance (e.g., Azure Data Box, Google Transfer Appliance, AWS Snowball) for the provider to load in their data center.

Offline migrationMigrating by taking the source offline and copying all data in a single pass, causing an outage during the copy.

On-demand pricingPay-as-you-go per-second/per-hour cloud pricing with no commitment — the most flexible but most expensive option, best for spiky or short-lived workloads.

On-premisesIT infrastructure that a company owns and runs in its own facility (Fort Rusty in this course), as opposed to renting cloud resources.

On-premises (on-prem)Computing equipment an organization owns and runs in its own facility (its own data center), rather than renting from a cloud provider. In this course, Fort Rusty.

Online data transferMoving data over the internet or a dedicated network link (e.g., AWS DataSync, Azure Storage Mover, Google Storage Transfer Service).

Online migrationMigrating while the source stays live and changes are continuously synced, limiting downtime to a brief final cutover.

OrchestrationAutomated coordination of many containers — scheduling, scaling, self-healing, networking, and rolling updates — typically handled by Kubernetes.

Over-provisioningAllocating more cloud resources (CPU, memory, storage) than a workload actually needs, wasting money continuously.

PaaS (Platform as a Service)Renting a managed platform to run your applications without managing the underlying servers or operating systems.

PatternA named, reusable, proven solution to a commonly recurring problem — here, a repeatable recipe for part of a migration.

PCI DSSThe Payment Card Industry Data Security Standard, a set of controls required for systems that store or process payment-card data, often shaping network segmentation and encryption in a migration.

Phased / wave-based migrationMoving workloads in small, sequenced batches ('waves') so each can be validated before the next begins.

PilotA small, low-risk trial migration used to prove the process and build skills before scaling up.

Pilot / Proof of Concept (POC)A small, low-risk trial migration used to validate the plan, tools, and landing zone before the full move.

Pilot light (DR strategy)A DR pattern where a minimal core of the system (e.g., replicated data and a switched-off app tier) stays ready in the cloud and is scaled up during a disaster — lower RTO/RPO than backup-and-restore at moderate cost.

POC / PilotA proof of concept (POC) or pilot: a small-scale trial migration used to validate an approach, tools, and assumptions before committing to a full-scale move.

Portfolio assessmentInventorying every application and scoring it on consistent criteria to decide which R each one gets.

Portfolio assessment / rationalizationScoring every application to choose a migration strategy for it and deliberately shrinking the estate by retiring or consolidating apps.

RationalizationThe portfolio-assessment step of deciding, per application, whether to retire, retain, repurchase, replatform, rehost, relocate, or refactor it.

Re-architectRedesigning an application's fundamental structure — for example, breaking a monolith into microservices — and AWS's alternate name for the Refactor strategy.

RefactorIn migration, the strategy of substantially rewriting an application to take full advantage of cloud-native features; note that in classical software engineering (Martin Fowler) 'refactoring' more narrowly means restructuring code without changing its external behavior.

Refactor / Re-architectSubstantially redesigning an application to use cloud-native features (e.g., microservices, serverless). The most complex, costly, and highest-benefit R.

RegionA distinct geographic area where a cloud provider clusters its data centers, letting customers place resources close to users or within specific legal jurisdictions.

RehostA migration strategy (also called 'lift and shift') that moves an application to the cloud as-is, with no changes to its code or architecture — simply carry the whole box over and set it down.

Rehost (lift and shift)Moving an application to the cloud unchanged. Fast and low-risk, but captures few cloud benefits until later optimized.

Rehost / Lift and shiftMoving an application to the cloud as-is, with no changes to the app itself.

RelocateMoving many servers at once at the hypervisor or container level (e.g., a VMware environment to VMware Cloud on AWS) without changing the OS or application.

Replatform'Lift, tinker, and shift' — making small optimizations (such as adopting a managed database) during migration without changing the core architecture.

Replatform / Lift, tinker, and shiftMoving an application to the cloud while making a few targeted optimizations, without rewriting its core architecture.

ReplicationKeeping a synchronized copy of a database, typically via the database engine's built-in mechanism.

RepurchaseA strategy (sometimes 'drop and shop') of retiring an existing application and replacing it with a ready-made commercial product, usually a SaaS subscription — throw out the old furniture and buy new.

Repurchase / Drop and shopRetiring an existing application and replacing it with a different, ready-made product — usually a SaaS subscription.

Reserved Instance / Committed-Use DiscountA pricing model where you commit to a specific amount of compute for 1–3 years in exchange for a large discount (often 30–70%) versus on-demand. Best for steady, predictable workloads such as rehosted always-on servers.

RetainDeliberately keeping an application in its current environment for now, planning to revisit migrating it later.

RetirePermanently decommissioning (shutting down) an application because it no longer has business value.

Right-sizingAdjusting resource allocations to match actual usage, a core cost-optimization technique.

ROI (Return on Investment)A measure of whether an investment's benefits were worth its cost; for migration, whether savings and value earned back the TCO within the planning horizon.

RollbackQuickly reverting to the previous working version when a change causes problems.

Rollback / backout planA predefined, tested procedure to return to the previous working state if a migration cutover fails.

Rolling deploymentA release technique that gradually replaces instances of the old version with the new one, a few at a time, until the entire fleet is updated without full downtime.

RPO (Recovery Point Objective)The maximum acceptable amount of recent data loss, expressed as a time window (e.g., 15 minutes).

RTO (Recovery Time Objective)The maximum acceptable time to restore a service after an outage.

RunbookA documented, step-by-step procedure for performing an operation (like a cutover), specifying tasks, owners, and order.

SaaS (Software as a Service)Ready-to-use software accessed over the internet (e.g., email, CRM), where the provider manages almost everything.

Savings PlanA flexible commitment-based discount (e.g., AWS Savings Plans) where you promise a steady hourly spend for 1–3 years and get lower rates across eligible compute, without locking to a single instance type.

ScalabilityThe ability to increase capacity to handle more load. In the cloud this is often near-instant compared with buying physical hardware.

Schema conversionTranslating a database's structure — tables, data types, and code like views and stored procedures — from the source engine's rules to the target engine's rules.

Schema Conversion Tool (SCT) / DMS Schema ConversionAWS tooling that converts a database's structure, data types, and stored code from one engine to another so DMS can then move the data.

Security-by-designBuilding security controls in from the very start of the design rather than bolting them on afterward.

ServerlessA cloud execution model where the provider automatically provisions and scales compute on demand and you pay only for actual usage; you manage code, not servers.

Shared responsibility modelThe framework dividing security duties: the provider secures the cloud itself; the customer secures what they put in it (data, access, configuration). The split shifts by service model.

Shift left (security)Addressing security early in the design and build process rather than bolting it on after deployment.

Site-to-site VPNAn encrypted network tunnel between two sites carried over the public internet.

SLA (Service Level Agreement)A formal contract between a provider and customer that defines the guaranteed level of service, such as an uptime percentage, and the remedies if it is not met.

SOC 2An independent audit report attesting that a service organization meets defined security, availability, and confidentiality controls — frequently required of cloud providers and cloud-hosted SaaS.

Spot / Preemptible InstanceSpare cloud capacity sold at a steep discount that the provider can reclaim with little notice. Ideal for fault-tolerant, interruptible work (batch jobs, testing); unsuitable for stateful, always-on services.

Storage tier (hot / cool / cold / archive)Pricing tiers that trade retrieval speed/cost for storage cost; frequently-accessed 'hot' data costs more to store but is instantly available, while 'archive' tiers (e.g., Glacier) are very cheap to store but slow/costly to retrieve — a key cost lever for rarely-used data.

Strangler Fig patternAn incremental modernization pattern (coined by Martin Fowler) where new functionality gradually replaces a legacy system piece by piece behind a façade, until the old system can be retired.

Success metrics / KPIsMeasurable targets defined up front (e.g., % cost reduction, latency, uptime, migration velocity) that define what a successful migration looks like.

TaggingAttaching metadata labels (owner, environment, cost center, project) to cloud resources so spend and ownership can be tracked and reported.

TCO (Total Cost of Ownership)The complete cost of an option over several years, including direct costs (compute, storage, network) and indirect ones (migration, training, security, downtime).

Technical debtDeferred work and shortcuts that accumulate over time and cost more to fix later — a risk of over-using Retain.

TerraformHashiCorp's multi-cloud IaC tool that uses the HCL language and tracks infrastructure in a state file.

The 7 RsSeven named migration strategies — Rehost, Replatform, Repurchase, Refactor/Re-architect, Retire, Retain, Relocate — popularized by AWS, building on Gartner's earlier framework.

Vendor lock-inDifficulty or cost of moving away from a provider or product because your systems depend heavily on its specific features. A key long-term risk.

Virtual machine (VM)A complete computer — operating system and all — packaged as a software file that runs on shared physical hardware. In this course, a 'room folded flat' for travel.

VM (Virtual Machine)A software 'computer' that runs on shared physical hardware, with its own operating system and apps, as if it were a separate machine.

VMware HCXA VMware migration and mobility platform for moving virtual machines (including live vMotion) between data centers and clouds.

VPC (Virtual Private Cloud)A logically isolated, private network within a public cloud where a customer controls IP addressing, subnets, routing, and security.

Warm standby (DR strategy)A scaled-down but running copy of the workload kept in the recovery environment, ready to scale to full size quickly — low RTO/RPO at higher ongoing cost than pilot light.

Wave planningGrouping applications into ordered batches ('waves') and migrating one batch at a time by dependency, risk, and priority.

Well-Architected FrameworkThe AWS Well-Architected Framework: design principles and best practices organized into six pillars — operational excellence, security, reliability, performance efficiency, cost optimization, and sustainability — for building and reviewing cloud workloads.

WorkloadA defined unit of computing work — such as a website, a payroll job, or an analytics pipeline — and the resources it needs. In this course, the 'furniture.'

Zero trustA security model defined in NIST SP 800-207 based on 'never trust, always verify' — every access request is continuously authenticated and authorized with least privilege, regardless of network location.

Zombie / idle applicationAn app with near-zero (zombie) or very low (idle) resource usage — a prime candidate to retire rather than migrate.

Zombie applicationAn app with very low resource usage (AWS cites average CPU/memory below ~5%) that is a strong candidate to Retire.