Azure Interview Questions

Azure Interview Questions Download Azure Interview Questions PDF

Azure Interview Questions

The developers, who have a hosting account, can use a Windows Azure portal to submit applications to Windows Azure. A developer can easily access the Windows Azure portal through the Web browser, by signing in with a Windows Live ID to run an application.

A table is a type of Azure Storage, where one can store the data as memory storage. Blobs are stored in container and Entity in the table.

The key concepts in the table are explained below:

  •  Tables allow structure data storage
  •  There can be 0..n tables in a storage account
  •  Table store data as a collection of entities
  •  Entity have a primary key and properties as a key value pair

Virtual machine scale sets are Azure compute resources, which can be used to deploy as well as manage a set of identical VMs. When all the VMs are configured in the same way, scale sets are automatically designed to support true auto-scale, and no pre-provisioning or prearrangement of VMs is required. That is why it is easier to build large-scale services, which target big compute, big data, and containerized workloads.

A scale set is an implicit availability set with five fault domains and five update domains. Scale sets of more than 100 VMs span multiple placement groups, which are equivalent to multiple availability sets. An availability set of VMs can exist in the same virtual network as a scale set of VMs. A common configuration is to put control node VMs (which often require unique configuration) in availability set and put data nodes in the scale set.

The SLA ensures that, when you send two or more role instances for each role, access to your cloud service will be maintained not less than 99.95 percent of the time. Furthermore, identification and re-correction activity will be started 99.9 percent of the time when the procedure of a role instance is not running.

Scaling by including extra instances is frequently referred to as scaling out. Windows Azure similarly supports scaling up by employing a bigger role instead of more role instances. By adding and expelling role instances to your Windows Azure application while it is running, you can adjust the execution of the application against its running costs. An auto-scaling solution simply diminishes the amount of manual work engaged in dynamically scaling an application.

Federation is introduced in SQL Azure for scalability. It helps administrators by making repartitioning and redistributing of data easier and thus, helps with scaling data. It helps developers in the routing layer and the sharding of data. It helps in routing without application downtime. Federation does basic scaling of objects in a SQL Azure Database. Federations are the partitioned data. There can be multiple Federations within a database. Moreover, each Federation represents a different distribution scheme. We create a Federation with a different distribution scheme and requirement. Student and Grade’s tables of a School Database may have a different distribution requirement, so they are put into different Federations.

VNet is a representation of your network in the cloud. It logically isolates the instances launched in the cloud, from the rest of the resources of a user.

The firewall checks access to the originating IPs from which a user may try to access the database. To configure the firewall, we need to configure a range of acceptable IP addresses upon which we try to connect to the SQL Azure server using the Management Portal or with the SQL Server Management Studio. All access to SQL Azure is blocked by a firewall.

By default Database created in SQL Azure is blocked by the firewall for maximized security. SQL Azure firewall rules are provided to protect the data and to prevent access restrictions to the SQL Azure database.

Redis is an open source, BSD licensed in-memory data structure store, which is commonly used as a database, cache and message broker. Azure Redis Cache is also based on this. It gives you access to a secure, dedicated Redis cache, managed by Microsoft, and accessible from any application within Azure.  It supports data structures such as strings, hashes, lists, sets, and sorted sets with range queries, bitmaps, hyperlog logs and geospatial indexes with radius queries.

It is different from other Azure services as unlike some of the other available services; Azure Redis Cache does not have an MSDN class library reference. This is because each client has its API that makes calls to the Redis cache instance using Redis commands. That is why there is not one centralized class reference on MSDN, and each client maintains its reference documentation.

Azure Queues provides the user with a solid, diligent messaging between and within the services. It also highlights quite a straightforward rest-based get/peek/put interface. The Azure Storage Queues make use of the local Azure Storage Emulator and debugging is made quite easy. The tooling for Azure Storage Queues allows you to easily peek at the top 32 messages and if the messages are in XML or JSON, one can visualize their contents directly from Visual Studio. Moreover, these queues can be purged of their contents, which is especially useful during development and QA efforts.

On the other hand, Bus Queues are part of a more far-reaching Windows Azure messaging framework, which supports queuing. As a rule, Azure Service Bus Queues can delete themselves after a configurable amount of idle time. This feature is very practical when you create Queues for each user because if a user hasn’t interacted with a Queue for the past month, it automatically gets clean it up. It is also a great way to reduce costs. However, these Queues are limited to a maximum of 80 GB. Once the user has reached this limit, his or her application will start receiving exceptions.

Each data disk on the VM can be up to 1 TB. However, the number of data disks, which you can use depends on the size of the virtual machine. Azure storage accounts can also provide storage for the operating system disk and any data disks where each disk is a .vhd file stored as a page blob.

Azure Managed Disks are the new and recommended disk storage offerings for use with Azure Virtual Machines for persistent storage of data. A user can use multiple Managed Disks with each VM. Managed Disks offer two types of durable storage options: Premium and Standard Managed Disks.

A hybrid cloud is a mixture of internal and external cloud services, a combination of a private cloud combined with the use of public cloud services. This type of cloud is most suitable when you want to keep the confidential data in your premise (private cloud) and consume the other services from a public cloud.

Advantages of Hybrid Cloud:

  • Scalability: Usually the Private Cloud services will have a lesser scalability due to its security, cost and compliance whereas the Public Cloud has a high scalability and moving non-sensitive data from the private to the public will free up resources in the data centers in the Private Cloud and that increases a very high scalability for a Hybrid Cloud.
  • Cost-effectiveness: Similarly the Public Cloud is very cost effective rather than Private Cloud, and here the Hybrid Cloud provides cost effectiveness with the data and other sensitive operations secured.
  • Security: Since there is a Private Cloud used; the data and sensitive operations are secured highly in the Hybrid Cloud.
  • Flexibility: We can easily move out of the non-sensitive data and manage large scalability using a Public Cloud service along with the Private Cloud. So with the availability of large scalability using Public Cloud and security using Private Cloud an enterprise has a vast opportunity in developing for new needs.

The Traffic Manager allows users to control the distribution of user traffic of deployed Azure cloud services, Azure websites or any other endpoint. In this, the distribution of traffic includes Azure cloud services, Azure websites, and other endpoints. There are three different load-balancing methods provided by Azure. The Traffic Manager applies an intelligent routing policy engine to the Domain Name Service (DNS) queries on the domain names and then maps the DNS routes to the apt instances of the required applications.

Roles are simply servers in layman terms. They are managed and load balanced platforms like service virtual machines, which work together to achieve a common goal. There are three roles, which are implemented in Windows Azure:

  • Web Role: It gives a web solution that is completely front-end. This is similar to an ASP.NET application. When it is enabled, Azure gives IIS and required services.
  • Worker Role: It gives us solutions to all background service.  It can easily run long activities as well.
  • Virtual Machine Role: The virtual machines execute the roles of both, web and worker. The Virtual Machine Roles gives the consumer the ability to modify the virtual machine on which the web and worker roles are running.