aaaa

If a recovery solution takes 8 minutes to access the backup in a separate datacenter and another 6 minutes to instantiate new servers using the backed-up data, the RTO is _

14 minutes

DevOps can have a huge impact on: - Team structure - Traditional ways of conducting operations - Software architecture - All of the above

All of the above

Events of interest during service operation include - Software license usage - Status information from systems - Performance metrics from applications - Security information

All of the above

Which is an example of a post-deployment error? Choose the best answer. - Version dependencies existing among the components - A developer connected test code to a production database - Parameters for dependent systems were set incorrectly - All of the above

All of the above

Which is not a reason for DNS to return two or more IP addresses for a single URL? - Testing - Performance - Relability - All of the above

All of the above

What are the methods for early release testing?

Beta relealse, canary release (release to a few servers), or A/B release (canary but compare new and old server performance)

Define the build process, continuous integration, and automated testing

Build process: creating a component Continuous integration: checking whether it integrates with other modulese Automated testing: non-human testing - easier and more reliable

Netflix Eureka is an example of a cloud service registry that acts as a _ server

DNS

Describe the development practices that a team should use to improve both dependability and modifiability of their services

Defensive programming, end-to-end testing, environment testing, and timeout requests. Encapsulate the affected portions of a likely change

Discuss various organizational and cultural issues of adopting DevOps

Departmental clashes, more training

What is the significance of incident management with DevOps?

DevOps is useful: log the incident, categorize and prioritize it, escalate if necessary, resolve, and close the incident

What are the two methods for managing service demand of client requests?

Either monitor performance and adapt, or use SLAs to inform the client of their capabilities

Amazon's rules for teams require all teams to expose their data and functionality by reading each other team's datastore directly to avoid time consuming inter-team communication. - True - False

False

Deployment scripts is different from application code. Therefore, errors in deployment scripts such as misconfigurations will only affect the deployment process but not the application itself. - True - False

False

If a web page is implemented by a collection of microservices, then its scalability should be managed by the infrastructure of the entire web system, not each individual service, and should be independent to its SLA. - True - False

False

In order to remove the inter-team coordination, a design decision of system architecture should be made to allow each component to be allocated to a single (virtual) machine or container but avoid multiple components to be allocated to a single (virtual) machine. - True - False

False

One difference between ITIL's service transition and the DevOps approach is that DevOps assumes fairly large release packages where careful planning, change management, and so on are feasible—in contrast to the high-frequency small releases encountered in typical ITIL scenarios. - True - False

False

Releasing a new system or version of an existing system to customers is one of the most sensitive steps in the software development cycle. This is only true the system or version is for external distribution or is used directly by consumers. It does not cause any concern if the system or version is strictly for internal use. - True - False

False

We should prevent likely changes from rippling through a service by reducing its modules that implement the interfaces. - True - False

False

When user issues a command to create a VM, this user must also decide on which physical machine to create the VM instance - True - False

False

DevOps and continuous deployment require the implementation part of service transition to be highly automated so it can deal with high-frequency transition and provide better quality control - True - False

False (delivery part, not implementation part)

A feature toggle can be implemented by a "try-catch" statement with a global Boolean variable. - True - False

False, an if statement

Encapsulating either the affected portions of a likely change or the interactions that might cause ripple effects of a change is a good method for making a service run faster. - True - False

False, makes it more modifiable

Git is a distributed version control system. Using its push command, changes from the server are synchronized with the local repository. - True - False

False, pull command

Describe the activities that an IT operations group carries out and what activities are suitable for a DevOps approach

Hardware provisioning, software provisioning, IT provision, SLA provision, capacity planning, business continuity, information security

ITIL stands for _

Information technology infrastructure library

_ is the step in which the built executable artifact is tested - Integration testing - Pre-commit testing - Nonfunctional testing - User acceptance testing

Integration testing

Explain why traceability is critical to moving a system through the deployment pipeline

It allows the ability to recreate an exact environment for testing

What is the significance of cross-team coordination?

It is the most time consuming factor which DevOps attempts to minimize. It is important to ensure effort isn't duplicated and the code can be adjoined

Describe the overall architecture of microservice, including its coordination model, management of resources, and mapping among architectural elements

It is where each service provides a small amount of functionality and total functionality is derived from multiple services. They retain compatibility through architectural structure. The coordination model - an instance registers with the registry, client invokes the instance and queries the registry The service, component, or a client monitors its needs and provisions/deprovisions VMs as needed Each component should be self-contained and worked on by only one team

Discuss the importance of continual IT services improvement and how it is performed

Its main focus is to ensure that the business needs are being met: if they have not changed - improve efficiency; if they have - adapt

_ testing is a mechanism to continue to test even after placing a system in production or promoting it to normal production.

Live

The best way to determine if the system behaves in a defined way when assumptions about the environment hold or the user performs actions in the right order with the right inputs are not met is to run - A/B tests - Negative tests - Canary tests - Unit tests

Negative tests

Which one is an incorrect statement? - A service itself can be responsible for provisioning additional services - Amazon's autoscaling groups in collaboration with CloudWatch monitoring system can provision an instance when the load reaches a given threshold - A client or a component in the client chain can be responsible for provisioning instances of a service - None of the above is true

None of the above is true

Describe the computing characteristics of the cloud

On-demand self-service, seemingly unlimited elasticity, measured service

Which could be a source for dependability problems of a system? - Large amount of cross-team coordination - Mapping among architectural elements - Possible failure of an instance of a service - Mixed versions of third-party software and libraries used by a service

Possible failure of an instance of a service

What is the significance of RPO and RTO?

Recovery point objective - what is the maximum period for which data loss is tolerable? Consider different backup strategies. Recovery time objective - what is the maximum tolerable period for service to be unavailable? Use multiple data centers

Deployment pipeline does not contain the step of - Build and integration tests - Performance tests - Pre-commit tests - Requirement analysis

Requirement analysis

The CRM of Salesforce.com is a good example of - IaaS - PaaS - SaaS

SaaS

Define types of services available from cloud providers

SaaS - allows consumers to use applications on the cloud (email, games) PaaS - allows consumers to deploy applications on the cloud (web servers, database servers) IaaS - allows consumers to to handle storage and networks (virtual machines, load balancers)

Which is not a characteristic of the cloud? - Resource pooling - Self diagnosis - Rapid elasticity - Broad network access

Self diagnosis

Define the core concepts and phases of ITIL and IT services

Service Design - anything to be implemented must first be designed; Service Operation - where customers begin to use; Service Transition - everything inbetween such as development

_ are a subset of the automated acceptance tests that are used to quickly analyze if a new commit breaks some of the core functions of the application. - None of the above - User acceptance tests - Smoke tests - Unit tests

Smoke tests

Identify barriers to the success of DevOps

Some types of businesses lose more from frequent downtime than faster releases

Describe the infrastructure requirements to support the development and deployment process

Team members can work on different versions concurrently, one team's code doesn't overwrite another's, work isn't lost if a member leaves the team

The people involved in the Ops side of DevOps typically come from: - Technology experts - Service desk operations - Day-to-day provisioning of IT services - Consultants

Technology experts and Day-to-day provisioning of IT services

Identify crosscutting aspects of a deployment pipeline such as: Test harnesses Negative tests Regression tests Traceability of errors Small components Environment tear down

Test harnesses: collection of software used to test data and generate a report Negative tests: tests how a system responds to unexpected occurrences Regression tests: retesting functional code for new bugs Traceability of errors: used to find out which version of the code is running and reproduce bugs Small components: easier to test individually Environment tear down: dismantle unused environments to free resources

Explain why the unique aspects of the cloud could impact DevOps

The ability to create and switch environments simply, the ability to create VMs easily, the management of data

Explain the motivation for the DevOps movement

The longer a release takes, the more its benefits are lost; currently coordination is lacking

Describe the DevOps perspective

The two consistent themes are the emphasis on automation and relocation of Ops responsibilities to Devs

Identify issues of adopting or migrating from an existing architecture to a microservice architectural style

There can be latency, authorization needs to be carefully designed, and monitoring / debugging need to be modified

Explain Amazon's rules for teams to support their microservice architecture

There should be no communication between two teams except through a service's interfaces

What is infrastructure-as-code?

Treating environments / infrastructure with proper version control and testing, as you would with code

An architect involved in a DevOps project should ensure feature toggles are removed when the code they toggle has been placed into production and been judged to be successfully deployed. - True - False

True

An organization can introduce continuous deployment without major architectural modifications. - True - False

True

CA Technologies provides IT management solutions to their customers. They commissioned a survey in 2013. More than 50% of respondents of this survey said they were already seeing an increased frequency of deployment of their software or services. - True - False

True

Chef is a configuration management tool that can be used to maintain traceability of errors because of its capability of keeping track of all changes it applies to a machine. - True - False

True

Continuous deployment is the DevOps practice that leads to the most far-reaching architectural modifications. - True - False

True

Dev and DevOps are becoming more responsible for application SLAs and external SLAs in the DevOps movement - True - False

True

In cloud computing, a virtual machine is an emulation of a physical machine - True - False

True

The language you wish to expose to the user is an example of configuration setting (or parameter). - True - False

True

The main reason of making multiple instances of a service be available is to support a load too heavy for a single instance and to guard against failure. - True - False

True

Explain whether or not DevOps practices require architectural change

Typically no. However, many businesses that adotp continuous deployment willingly change to microservice-based architectures

Describe the importance of versioning and branching, feature toggles, configuration parameters, and pre-commit testing

Versioning and branching: identify distinct versions of code, share revisions between devs, and log changes Feature toggles: disable features not ready to test Configuration parameters: externally settable variable that changes the system (language, file location) Pre-commit testing: Test-driven development (code is written to pass tests) or unit tests (test is written to test individual code)

Identify features of virtualization

Virtualization is emulating a physical machine by using partial resources of one; a vm image is the boot; a heavily baked image means it's fully self-contained

Differentiate between methods of SDLC

Waterfall Model: each stage is completed sequentially with no overlap The Iterative Model: starts with a small set of requirements and repeatedly builds onto it The Spiral Model: breaks into four phases and iterates within each one to completion The V Model: Every phase has a test period The Big Bang Model: Very little planning

With cloud elasticity, the pay-as-you-go model, and the ease of provisioning new virtual hardware, capacity planning is becoming more about runtime monitoring and _ rather than planning for purchasing hardware

autoscaling

The CDC testing practice requires the test cases for testing a microservice to be decided and even co-owned by all the _ of that microservice.

consumers

The seven-step process suggested by ITIL for continual service improvement is a _ -driven process

data

One method of viewing the relationship between DevOps and ITIL is that DevOps provides continuous _ of the various ITIL services rather than requiring those services to be packaged into a major release.

delivery

A _ consists of the steps that are taken between a developer committing code and the code actually being promoted into normal production, while ensuring high quality

deployment pipeline

In cloud computing, a VM _ is a file that contains a bootable operating system and some software installed on it.

image

Controlling tools by scripts is far better than controlling tools by commands. The scripts and associated configuration parameters should also be kept under version control, just as the application code. This new movement is called _

infrastructure as code

An important trend in DevOps is to manage all the code and parameters for setting up an environment just as you manage your application code, with proper version control and testing. This is an example of _

infrastructure-as-code

In a discussion of VM in Chapter 2, simple requests such as computation, reading a file, or receiving a local message will have a distribution closer to normal. Complicated requests such as extensive map-reduce jobs, searches across a large database, or launching virtual instances will have a skewed distribution such as a _

long tail

The DevOps goal of minimizing coordination among various teams can be achieved by using a _ architectural style where the coordination mechanism, the resource management decisions, and the mapping of architectural elements are all specified by the _ and hence require minimal inter-team coordination.

microservice, architecture

Two methods are discussed in Chapter 4 for managing demand on the service from client requests. One is to monitor _ and the other possible technique is to use _ to control the number of instances.

performance, SLAs

DevOps is a set of _ intended to reduce the _ between committing a change to a system and the change being placed into normal production, while ensuring high _

practices, time, quality

One category of DevOps practices identified in the textbook is to treat Ops as first-class citizens from the point of view of _

requirements

ITIL v3 emphasizes the concept that IT is a _ that supports business goals

service

Among several DevOps team roles, _ is responsible to maintain and communicate the vision for the service assigned to develop by the team.

service owner

Before writing the actual code for a piece of functionality, you develop an automated test for it. Then the functionality is developed, with the goal of fulfilling the test. This philosophy is called _

test-driven development

Define DevOps

the set of practices intended to reduce the time between deploying high quality content

The ITIL service life cycle consists of service strategy, service design, service _ , service operation, and continual service improvement

transition

Development at Google is _ -based rather than _ -based. Instead of reintegrating a big branch, their developers deal with integration issues at each _ , which is a simpler solution, but requires more frequent action than using branches.

trunk, branch, commit