Azure Cloud computing

What is Azure cloud computing? 

Azure is a cloud computing platform and infrastructure created by Microsoft for building, deploying, and managing applications and services through a global network of Microsoft-managed data centers. Azure provides a wide range of services including virtual machines, web applications, databases, and storage, among others. It allows developers and organizations to build, test, and deploy applications in the cloud, reducing the need for physical hardware and maintenance costs. With Azure, organizations can scale their resources as needed, quickly and easily provision new services, and benefit from the security, privacy, and compliance features of a world-class cloud computing platform.

What are the different cloud deployment models?

Azure cloud deployment models are:

1. Public Cloud: Azure resources are provided to the general public over the internet.
2. Private Cloud: Azure resources are dedicated to a single organization and are not shared with other organizations.
3. Hybrid Cloud: Combines the benefits of both public and private clouds to meet specific business requirements.

Each deployment model has its own advantages and disadvantages, and the choice of deployment model depends on the organization's specific requirements and preferences.

What are virtual machine scale sets in Azure?

Virtual Machine Scale Sets (VMSS) are a feature in Microsoft Azure that enables you to deploy, manage, and scale a set of identical, load-balanced virtual machines. These virtual machines can automatically increase or decrease in number based on demand, making it easy to manage large-scale applications that need to scale up and down. VMSS provides high availability, automatic instance replacement, and automatic scaling of the number of virtual machines in a scale set. This makes it an ideal solution for deploying web applications, big data processing, batch processing, and other types of workloads that need to scale dynamically.

What is an Availability Set?

An Availability Set is a feature in Microsoft Azure that helps ensure high availability for virtual machines (VMs) by automatically distributing them across multiple physical servers, network switches, and storage units within an Azure datacenter. The primary purpose of an Availability Set is to provide resiliency against potential failures of individual hardware components, such as servers or storage units, which could cause VMs to become unavailable. By using an Availability Set, customers can ensure that their VMs are running on different physical servers and that if one server fails, another server is available to take its place, thereby reducing downtime and improving the reliability of their workloads.

What are Fault Domains?

A fault domain is a group of Azure resources that share a common power source and network switch. When you deploy a virtual machine (VM), the system automatically places it in an availability set to ensure that if the underlying hardware fails, the VM continues to run on another host. In an availability set, VMs are separated into one or more fault domains, so that if an entire rack or data center goes down, only a portion of the VMs are impacted. This way, Azure provides resiliency to your application by ensuring that VMs are spread across different fault domains.

What are Update Domains?

Update domains are a feature of Azure that provides a way of dividing a set of virtual machines into small groups. The purpose of update domains is to provide a way to upgrade the virtual machines in a phased manner, with the aim of reducing the impact of planned maintenance on the availability of the application. During a planned maintenance operation, only one update domain is taken offline at a time, which helps to ensure that the overall application remains available even if some of the virtual machines are undergoing maintenance. This helps to provide high availability for the application during planned maintenance operations.

What are Network Security Groups? 

Network Security Groups (NSG) are a fundamental component of Azure networking, providing access control for inbound and outbound traffic to and from Azure virtual machines (VMs) and other resources. NSGs contain access control rules that determine which traffic is allowed or denied based on source and destination IP addresses, port numbers, and protocols. NSGs can be associated with one or more subnets within a virtual network, allowing you to secure communication between resources within the same subnet or between different subnets. NSGs can also be associated with individual VMs, providing an additional layer of security for controlling access to specific resources.

Do scale sets work with Azure availability sets?

Yes, virtual machine scale sets in Azure can work with availability sets. An availability set is a feature of Azure that provides high availability to an application by distributing the application instances across multiple isolated hardware nodes, known as fault domains. By distributing the instances across multiple fault domains, an availability set helps to ensure that the application is not affected by single points of hardware failure. By placing the virtual machines in a scale set in an availability set, you can improve the availability of the virtual machines and help to ensure that the application remains available during planned or unplanned maintenance events.

Why is Azure Active Directory used?

Azure Active Directory (AD) is used for centralized identity management and access control for various services and applications. It provides features like single sign-on (SSO), multi-factor authentication (MFA), and user and group management to secure access to resources and simplify identity management tasks. Azure AD also integrates with other Azure services and third-party applications, providing a seamless user experience and enabling organizations to securely manage access to their resources. With Azure AD, organizations can streamline user management and improve the security of their applications and services, making it a valuable tool for businesses of all sizes.

What happens when you exhaust the maximum failed attempts for authenticating yourself via Azure AD?

The maximum number of failed attempts to authenticate yourself via Azure Active Directory is typically set by the organization or administrator managing the Azure AD instance. When the maximum number of failed attempts is reached, access to the Azure AD-protected resources is typically locked or restricted until the user is able to reset their password or take other action to regain access. The exact behavior in such cases can depend on the security policies and procedures set by the organization.

What is Azure Service Fabric?

Azure Service Fabric is a distributed systems platform that makes it easy to build, deploy, and manage scalable and reliable microservices and containers. It provides a common infrastructure for building, deploying, and managing applications across multiple machines and data centers, making it possible to build, deploy, and operate large-scale, high-performance, and always-available services. Azure Service Fabric provides a variety of primitives, such as service discovery, communication, state management, and health monitoring, that make it easier to build, test, and operate complex, multi-tier, and highly-available applications.

What is a VNet?

A Virtual Network (VNet) in Azure is a representation of an isolated network environment in the cloud. It is used to securely connect Azure resources to each other, to the internet, and to on-premises networks. A VNet allows you to define a custom IP address space, create subnets, and configure network security and access. This provides a level of control and security for communication between your resources in Azure and helps ensure your applications are deployed in a manner that meets your security and compliance requirements.

What is Azure Redis Cache?

Azure Redis Cache is a managed, in-memory data store that is based on the open-source Redis cache. It provides access to a secure and dedicated Redis cache, managed by Microsoft. The cache can be used as a high-performance data store for applications that require fast, low-latency access to data, such as real-time analytics, content management, and gaming. Azure Redis Cache supports a wide range of data structures, including strings, hashes, lists, and sets, making it a flexible data store that can be used to store and retrieve many different types of data. Additionally, Azure Redis Cache supports various persistence options, allowing you to persist data to disk in order to prevent data loss in the event of a cache restart.

What are Redis databases?

Redis databases are in-memory data stores that are used to store key-value pairs. They are often used as a cache layer or as a persistent store for real-time data. Redis databases are fast and highly scalable, and they provide a range of data structures and commands that allow developers to store, retrieve, and manipulate data in complex ways. Some of the common use cases for Redis databases include session management, leaderboards, real-time analytics, and real-time notifications.

What is Azure Search?

Azure Search is a fully managed search-as-a-service solution provided by Microsoft Azure. It is used for indexing, searching and analyzing large amounts of data, and enables developers to add search functionality to their applications. Azure Search can index data from a variety of sources including Azure SQL Database, Azure Cosmos DB, and Blob Storage, and supports full-text search, geospatial search, and faceted navigation. With its powerful search algorithms and API, Azure Search makes it easy for developers to provide fast, relevant search experiences to their users.

What are stateful and stateless microservices for Service Fabric?

In Service Fabric, microservices can be either stateful or stateless.

Stateless microservices do not maintain any state between requests, they only process the incoming request and return a response. They are typically used for tasks such as processing requests, managing data access, and performing simple computations.

Stateful microservices, on the other hand, maintain state across multiple requests. They are used for tasks that require the preservation of state, such as session management, user profile data, or shopping cart data. In Service Fabric, stateful microservices store their data in reliable collections, which provide durability guarantees and enable the service to recover from failures.