Describe cloud concepts
Domain 1 of AZ-900 accounts for 25-30% of the exam. EarnYourCert has 132 original questions for this domain, all with explanations: 85 multiple choice, 27 yes/no and 20 completion or ordering items, like the real exam.
What this domain covers
- Shared responsibility model across IaaS, PaaS and SaaS
- Public, private and hybrid cloud
- Capital (CapEx) vs operational (OpEx) expenditure and consumption-based pricing
- High availability, scalability, elasticity and reliability
Domain 1 sample questions
8 questions from our 132-question bank for this domain. Try to answer before revealing the solution.
1. Which cloud characteristic refers to resources being accessible over the network from different types of devices, such as laptops or phones?
- Centralized governance
- Broad network access
- Vendor lock-in
- Economy of scale
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Correct answer: B. Broad network access refers to cloud resources being available over the network and accessible through standard mechanisms from different types of devices.
2. Which advantage best describes the fact that a customer can create an account and start using Azure services without signing a long-term contract beforehand?
- Low barrier to entry and immediate self-service
- A requirement for prior government approval
- A requirement to buy physical hardware first
- A requirement to sign an Enterprise Agreement
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Correct answer: A. Being able to create an account and start using services immediately, without long-term contracts or large upfront investments, lowers the barrier to entry and allows for quick experimentation.
3. What term describes a system's ability to continue functioning correctly even when one or more of its components fail?
- Fault tolerance
- Granular billing per resource and per hour
- Governance through Azure Policy definitions
- Predictability of performance and cost
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Correct answer: A. Fault tolerance is the ability of a system to continue operating correctly despite the failure of one or more of its components, typically through redundancy and resilient design.
4. How does cloud elasticity help avoid over-provisioning resources for infrequent traffic spikes?
- It removes the need to ever measure traffic
- It forces maintaining maximum capacity at all times
- It requires permanently buying additional servers
- Adds capacity only during spikes, then scales it back
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Correct answer: D. Elasticity allows adding extra capacity only during demand spikes and scaling it back down when no longer needed, avoiding payment for oversized resources the rest of the time.
5. How does the cloud reduce an organization's need to maintain a second physical datacenter solely for disaster recovery?
- It completely eliminates the need for backups
- Allows replicating data to another region on demand
- It requires permanently doubling the IT staff
- It requires building a second identical building
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Correct answer: B. The cloud allows replicating data and workloads to another region on demand, without needing to build and maintain a second physical datacenter solely for disaster recovery.
6. A company needs a globally distributed NoSQL database with guaranteed low latency and automatic scaling, without having to install or manage any database engine. Which Azure service and service model best fit this requirement?
- Azure Cosmos DB, a fully managed PaaS database service
- A virtual machine with MongoDB installed manually, as an example of IaaS
- Microsoft 365, as an example of SaaS for data storage
- Azure Functions, as an example of FaaS for persistent data storage
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Correct answer: A. Azure Cosmos DB is a fully managed (PaaS) NoSQL database service that offers global distribution, SLA-guaranteed low latency, and automatic scaling, without the customer needing to install or manage a database engine. A virtual machine with MongoDB installed manually would be an IaaS approach, where the customer would have to manage the database engine, exactly what's meant to be avoided. Microsoft 365 is a SaaS productivity suite, not a database service. And Azure Functions is a serverless compute service for running code, not designed as a primary persistent data store.
7. A company is deciding between hosting its website on a virtual machine (IaaS) or on Azure App Service (PaaS). If they choose App Service, which of the following tasks will ALWAYS remain the company's responsibility, regardless of the model chosen?
- Configuration of the data center's physical network where the Azure App Service is hosted
- Physical and logical maintenance of the underlying servers running the Azure App Service Plan
- Applying security patches to the underlying operating system that Azure App Service manages automatically
- The application code, its specific configuration, and management of the data it handles
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Correct answer: D. Regardless of whether IaaS or PaaS is used, the customer is always responsible for their application code, its specific configuration, and the data it handles, since these elements are exclusive to the customer in both models. Patching the operating system is the customer's responsibility in IaaS, but Microsoft's in PaaS, so it isn't constant. Physical maintenance of servers is always Microsoft's responsibility, in any model. And configuration of the data center's physical network is also always Microsoft's responsibility, the customer never manages that layer.
8. An insurance company uses SharePoint Online within Microsoft 365 to manage internal documents. A new employee asks whether the company needs to manage security updates for the server running SharePoint. What is the correct answer?
- No, because the company has no security responsibility at all when using SharePoint Online
- Yes, because in any cloud-based service the customer must always apply server updates
- No, because SharePoint Online is a SaaS service and Microsoft manages all the infrastructure and server updates
- Yes, but only if the company chose a basic-tier Microsoft 365 plan
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Correct answer: C. SharePoint Online is a SaaS service within Microsoft 365, meaning Microsoft handles all the underlying infrastructure, including the operating system, the server, and its security updates. It isn't true that the customer must always apply server updates in any cloud service, that varies by model (it's true in IaaS, but not in SaaS). The company does have security responsibilities, such as managing identities, permissions, and document classification, but not over the server infrastructure. And this management by Microsoft doesn't depend on the plan tier purchased, it's inherent to the SaaS model.