Cloud Basics

Question 1

What 5 characteristics define a cloud?

Answer 1

Resource Pooling, Rapid Elasticity, Metered Usage, Broad Access, Self Provisioning

Question 2

What is load balancing?

Answer 2

Evenly distributing incoming network traffic across a group of backend resources (i.e. servers)

Question 3

Describe rapid elasticity.

Answer 3

Capabilities can be elastically provisioned and released, in some cases automatically, to scale rapidly outward and inward commensurate with demand.

Question 4

Describe metered usage.

Answer 4

Under a metered-billing pricing model, the cloud-based application must be able to track your usage level and automatically calculate a price that matches your usage level

Question 5

Describe resource pooling.

Answer 5

The provider’s computing resources are pooled to serve multiple consumers using a multi-tenant model, with different physical and virtual resources dynamically assigned and reassigned according to consumer demand. This allows customers to change their levels of service at will without being subject to any of the limitations of physical or virtual resources.

Question 6

Describe self provisioning.

Answer 6

Self-provisioning, commonly known as the cloud self-service, is a feature among many cloud service providers which allows their end users to provision resources by themselves, and set up or launch a service or application without the intervention of dedicated IT personnel or the service providers themselves.

Question 7

Describe broad access.

Answer 7

The cloud characteristic of Broad Network Access means that the service can be accessed from multiple locations (such as from a corporate office or from home) using multiple different types of client (such as a Windows PC or an Android mobile).

Question 8

What is CapEx?

Answer 8

It stands for CAPital EXpenditure and refers to the upfront cost associated with setting up a cloud system (e.g. server racks, operating systems, HVAC)

Question 9

What is OpEx?

Answer 9

It stands for OPerational EXpenditure and refers to the recurring expenses associated with the cloud (e.g. subscription costs)

Question 10

What are some benefits of using a cloud?

Answer 10

No CapEx required, cloud is responsible for securing their systems, quick to get going using cloud provider services, complexities are taken care of by cloud provider, less space required on-prem for hardware, HVAC

Question 11

What are the two basic services provided by all cloud providers?

Answer 11

Compute Power and Storage

Question 12

What is the Shared Responsibility Model?

Answer 12

A breakdown of who is responsible for which parts of the cloud system. Cloud service providers are always responsible for maintaining the physical hardware (datacenter servers, connectivity, HVAC) and the cloud customer is always responsible for handling stored data, dictating devices which can connect to the cloud, and setting up accounts and roles within the cloud.

This model is used when defining the different service types: Infrastructure as a Service (IaaS), Platform as a Service (PaaS), and Software as a Service (Saas). The share of responsibility shifts between the cloud service provider and cloud customer based on which service model is used.

Question 13

What are the three main types of clouds?

Answer 13

Private Cloud (cloud used by a single entity, sometimes hosted directly from your own datacenter)

Public Cloud (available to the general public)

Hybrid Cloud (Inter-connected environment of both private and public cloud resources)

Question 14

What are some benefits of the Consumption-Based Model?

Answer 14

No upfront costs
No upfront CapEx (Capital Expenditure) required
Ability to pay for resources as they are needed
Ability to stop paying for unnecessary resources

Question 15

What is a SLA and what are common up-time percentages?

Answer 15

Service Level Agreements (SLA) are contracts between the cloud provider and the cloud consumer that state specific regarding guaranteed up-time and any credits that may be owed to the cloud consumer if that particular service is down for more than that percentage of time.

In Azure, 99%, 99.9%, 99.5% and 99.99% are common up-time guarantees.

Question 16

Describe Vertical Scaling and Horizontal Scaling.

Answer 16

Vertical scaling is focused on increasing or decreasing the capabilities of resources. Horizontal scaling is adding or subtracting the number of resources.

Analogy: Say you are a company looking to increase productivity. Vertical scaling would be training your current employees to perform more tasks. Horizontal scaling is hiring more employees.

Question 17

When would it make the most sense to use IaaS?

Answer 17

In any instance when you need the most control over how the cloud services function. This is especially common in Lift-and-Shift scenarios when you need to replicate the existing structure of an on-prem system in the cloud where you already have a system in place for handling network controls, OS patches and updates, etc.

Question 18

When would it make the most sense to use PaaS?

Answer 18

In instances where you don’t need fine-grained control over all aspects of provisioning a service, but desire the ability to customize some of the features. For instance, in analytics, it useful to have a tool that is kept up-to-date by the cloud provider that also allows you to define custom filtering methods for analyzing data.

Question 19

What distinguishes a sovereign region from a traditional Azure region?

Answer 19

They are isolated outside the main Azure instance and are generally reserved from government use.

Question 20

What is the difference between a region and an availability zone?

Answer 20

Regions are geographical areas that service large portions of a country. Availability zones are sections within a region that dictate which services are available in each zone. Availability zones within the same region are sometimes used as fallbacks when a zone experiences a failure or maintenance.

Question 21

Define a Resource and a Resource Group.

Answer 21

Resources are “Anything you create, provision, deploy, etc….” such as Virtual Machines or databases. Resource groups are groupings of these resources. Grouping resources makes it easier to apply restrictions or rules to all resources within a group at the same time.

Question 22

What is the difference between a Subscription and a Resource Group?

Answer 22

Subscriptions are one level up in the hierarchy than Resource Groups. Subscriptions define which services are available to a resource group and are responsible for authorization and access control of everything within the subscription.

You can have multiple subscriptions for your Azure account, each with unique access rules and resources. They are commonly used to create distinct development environments, separate resources based on the needs of different departments in an organization, or keep track of billing.

Question 23

What is a Management Group?

Answer 23

The next level up in the hierarchy above Subscriptions. They allow you to group together multiple subscriptions in order to apply the same rules to several subscriptions at once. These are most commonly needed in very large scale, enterprise applications where you might have teams across different regions or that have very different responsibilites or resource requirements.