After the introduction of cloud computing, many companies have started using this technology for storing, retrieving, and processing data over the Internet. It helps in enhancing the scalability, flexibility, availability of the data along with the reduced cost. Various companies offer resources for doing this, known as cloud service providers.
Among various options, we are considering and discussing Azure that was launched by Microsoft on 01 February 2010. By now Microsoft Azure has become one of the leading cloud service providers supporting more than 80 percent of the companies for hosting their applications and resources. Due to its increasing benefits, there is a great demand for Azure employees in the market. Thus here we are mentioning various Azure interview-related questions for a better understanding of Azure’s concept.
1. Explain cloud computing.
The term cloud computing refers to the usage of the computing resources on the Internet for storing, managing, and processing data. But instead of using and maintaining our servers, we use the server space provided by third parties like Microsoft, AWS, etc. on paying a certain amount as per the resource usage. Cloud computing improves the execution speed, flexibility, and availability of the data. It ensures high fault tolerance by distributing data to various servers on the same network.
2. Explain various cloud deployment models.
There are three models of cloud deployment.
Public cloud: In this model, the cloud providers publicly owned the cloud infrastructure that shares the server resources between various applications.
Private cloud: It is a dedicated cloud model privately owned by a specific organization and gets private services. The services are being hosted on the dedicated server provided by the cloud provider.
Hybrid cloud: It is a combination of both public and private cloud models. It is used in a scenario where you want to use the on-premise servers for data processing but using the public cloud features for hosting applications.
3. What is Azure?
Azure Cloud Service is an example of a platform as a service (PaaS) specially designed for supporting those applications that have a demand for high scalability, reliability, and availability while maintaining the reduced cost of operations. These are hosted on virtual machines (VMs) and Azure allows developers to have more control over them by letting them use the right software and enabling them to control remotely.
Azure cloud services are efficient for deploying multi-tier web-based applications by creating an instance of cloud service. You can also define multiple roles such as web roles, worker roles, etc. for carrying out the distributed processing.
4. Explain role instances in Azure.
A role instance can be considered as a virtual machine that runs the code of the application using running role configurations. There can be several instances for a role in the cloud service config files.
5. What type of cloud service roles are offered by Azure?
Cloud service roles consist of a set of application and configuration files. Azure offers two kinds of roles:
Web role: This role offers a dedicated web server that belongs to IIS (Internet Information Services) for automatic deployment and hosting of front-end websites.
Worker role: These roles host the applications within them to run asynchronously for a longer time and do not depend on the user interactions and do not use IIS. They are perfect to perform background processes. The applications can run in a standalone manner.
6. Explain different services offered by the cloud.
The cloud offers three different services.
IaaS (Infrastructure as a Service): In this, the cloud provider will provide you with raw hardware as a service. For example, you can get a server that can be configured as per your choice i.e. Azure VM.
PaaS (Platform as a Service): The cloud provider will offer you a platform for publishing without access to the underlying OS. For example, web apps in Azure.
SaaS (Software as a Service): The cloud provider will offer you software without the need to purchase it.
7. What is the scalability of cloud computing?
As per the Azure cloud, scaling is of two types — vertical and horizontal.
Vertical scaling: It ensures the scaling of the configurations of the machine. For example, scaling RAM size from 4GB to 32GB.
Horizontal scaling: It ensures the scaling of the physical aspect. For example, adding several machines to the cloud without impacting the performance.
8. Mention the advantages of cloud computing.
The advantages of using cloud computing are:
Cloud computing ensures data security by implementing various security measures in place like two-factor authentication and more.
It helps in reducing the cost of operation, hardware, resource, and services as the cloud service provider will charge on a pay-per-use basis, where you have to pay only for those services that you are using.
It allows various users to have complete control over the data that they have hosted on a particular cloud.
It ensures that your business will get flexible IT infrastructure where they will be able to scale their services and resources with growing business requirements.
It ensures to create a backup of your data on several machines over the network and prevent data loss during a disaster.
It ensures extensive scalability for the products to enhance the impact on the customers.
It helps in reducing the carbon footprint by making everything accessible via the Internet and not maintaining any physical location to work.
9. Why is Azure Diagnostic API required?
Azure Diagnostics API helps us in gathering the diagnostic data like performance monitoring, system event logs, etc. of all the applications running on Azure.
To ensure verbose monitoring of the data, Azure Diagnostics has to be enabled for the cloud service roles.
The diagnostics data is beneficial for building visual chart representations for efficient monitoring and generating performance metric alerts.
10. Explain Azure resource manager.
The Azure resource manager is a service in Azure that ensures the management and deployment of the applications in Azure. It offers a management layer allowing the developers to create, modify, or delete the resources from the Azure subscription account.
11. Explain Azure Redis cache.
Azure provides an open-source, in-memory Redis cache system and maintains it.
It helps in improving the performance of the web applications by getting data from the backend database and then storing it into the Redis cache for the first request and then accessing the data from the Redis cache for further requests.
Azure Redis Cache ensures a powerful and secure caching mechanism by using the Azure cloud.
12. Explain Azure virtual machine scale sets.
These are the Azure computation resources that help in deploying and managing the sets of identical VMs.
These scale sets are configured and designed for supporting the autoscaling of the applications without pre-provisioning the VMs.
They help in creating large-scale applications holding big data and containerized workloads more efficiently.
13. Steps to take when drive failure occurs.
You can follow the below-mentioned steps:
Make sure that the drive is not mounted for the proper functioning of the Azure storage functions.
Make sure to replace the drive for remounting and formatting the drive.
14. What is the Azure storage key?
Azure storage key is used to authenticate the access for the Azure storage service to access data.
There are two types of storage keys used by Azure:
Primary Access Key
Secondary Access Key
The secondary access key is used to avoid downtime of the website or application.
15. Explain CSPack in Azure.
It is a command-line tool that generates the service package files. The tool prepares the application for deployment in Microsoft Azure or computer emulator.
Every cloud service type project has the .cscfg file which is the cloud service configuration file generated using the CSPack tool and is primarily used to store the following:
The number of role instances for the deployment of each role in the project.
The certificate’s thumbprint.
User-defined configuration and settings.
16. How to execute code in Azure without a server?
You can use the Azure Functions service to execute the code without a server.
Also, you can use the Serverless Azure Functions to simplify complex orchestration and challenging resolutions.
17. What is Azure Blob Storage?
Microsoft offers an object storage solution for the cloud known as Azure Blob Storage. Blob is a short name for “Binary Large Object” that is used to store large and unstructured data in terms of text or binary format. It is a perfect solution for including documents/images/audio/video/text directly to the browser.
The data that is stored in Blob Storage can be accessed from anywhere in the world. You can attach the Blob to user accounts by grouping them into containers.
18. What are the components of the Azure Blob Storage?
Azure Blob Storage has three components:
Storage Account: You can register for the Blob Storage Account using Microsoft Azure.
Container: Container is used for grouping an unlimited number of Blobs. Make sure to use a lower case for naming the container.
Blob: A Blob is a Binary Large Object like a file or document of any type and size.
Azure supports three types of Blobs.
Block Blobs: These are used for text and binary files that can support up to 195GB, i.e. up to 50k blocks of up to 4MB each.
Append Blobs: These are used for appending operations like logging data in log files.
Page Blobs: These are used for frequent read/write operations.
19. Explain Azure scheduler.
Azure Scheduler helps in invoking certain trigger events or activities in the background like calling HTTP/S endpoints or to add a message scheduled on the queue.
Using Azure Scheduler, you will be able to execute the jobs present in the cloud call services available within and outside of the Azure on-demand that runs on a regular schedule or to schedule it for a future specified date.
20. Mention storage services provided by Azure apart from the Blob.
Azure offers four types of storage services — Blob Service, Table Storage, Queue Storage, and File Storage Services.
Azure Table Storage: It allows the user to deploy their applications with semi-structured data along with a NoSQL-based key-value store. It is used for applications following a flexible schema of data. It focuses on enterprise-level data that is represented in terms of Entities grouped under tables.
Azure Queue Storage: It offers a message queue system to handle a large workload. It eliminates the failure of the individual components of applications. You can use its message queue monitoring feature to ensure that the user demands are met.
Azure File Storage: It provides features for sharing files that are accessible using SMB (Server Message Block) Protocol. It improves the performance and capabilities of on-premise applications.
21. Explain the Dead-letter queue.
Messages will be transferred to the Dead-letter queue if it comes across the following situation:
When the message delivery count has exceeded that is in a queue.
When the message’s expiry date has crossed and that message is left in a queue.
When there is an evaluation exception set by default and the subscription has been enabled with a dead letter filter.
22. Explain Azure table storage.
Azure Table storage is a database that helps in storing NoSQL data. It allows you to store structured, schemaless data with the help of a key/attribute design. You can also use it for structured but non-relational data.
You can also use Azure Table storage via the Azure Cosmos DB Table API.
23. Mention benefits of Traffic Manager in Windows Azure.
The Traffic Manager helps in controlling the distribution of the user for deploying the cloud service. Below are the benefits of the Traffic Manager:
It makes the applications available worldwide using automated traffic control machinery.
The traffic managing service helps in providing high performance by making the loading of pages faster.
There is no wastage of time in upgrading the existing system. The system keeps on running in the background as the system takes time for up-gradation.
Using the Azure portal, you can make configuration easier.
24. Mention the challenges of using Microsoft Azure.
Some of the challenges that you might face while using Microsoft Azure are:
You might not be able to use the Azure cloud if you are not connected to the Internet.
It is a web-based application that requires a large bandwidth for downloading large documents.
You might feel that web-based applications are somehow slower than accessing the same application on a desktop.
25. Reasons for a client application to be disconnected from the cache.
There can be two major possible reasons for disconnection:
Client-side reasons:
Redeployment of application.
The application might have been scaled.
Change in client-side networking layer.
Transient errors that occurred in the client or the network between the client and the server.
Bandwidth threshold limits have been crossed.
Server-side causes:
The Azure Redis Cache service undergoes a failover from the primary to the secondary node.
Due to the patching or maintenance of the server instance where the cache was deployed.
26. Difference between Azure scale sets and availability sets.
| Criteria | Azure Scale Sets | Azure Availability Sets |
| Definition | Defined as the group of identically configured VMs spread across multiple fault domains. | Defined as the group of discretely configured VMs spread across various fault domains. |
| Default Domain | It has 5 fault domains and update domains by default. | It has 3 fault domains and 5 update domains. |
| Workload Type | You can use it with unpredictable workloads requiring the feature of auto scalability. | You can use it with the predictable workload requirements. |
| Configuration Style | VMs are configured and created in the same way using the same image. | VMs are created by using different images and configurations. |
| VM Count | You can increase or decrease the number of VMs according to the demand or the pre-defined schedule. | You can add a VM to an availability set only at the time of the creation of the set. |
| Distribution style | You can distribute the VM scale sets across multiple data centers or within a single data center. | The VMs are distributed in a data center automatically. |
27. Difference between the Azure Table Storage and Azure SQL Service.
| Table Storage Service | Azure SQL Table |
| It is a NoSQL type of storage available on Azure. | It is the relational storage structure available on Azure. |
| It stores the data in a key-value format that is referred to as Entity. | It stores the data in rows and columns combination in the SQL table. |
| It does not enforce the data schema for storage. | It enforces the data schema to store data and if there is a schema violation, then it will show an error. |
| There is no relationship between tables. | Foreign keys are used to define the relationships between tables. |
| For each entity, the partition and row key combinations are considered unique. | The user uses the primary or unique keys to ensure uniqueness. |
| It helps in storing log information or diagnostics data. | You can use it for transaction-based applications. |
28. Difference between Azure Storage Queue and Azure Service Bus Queue.
| Azure Storage Queue | Azure Service Bus Queue |
| It does not guarantee the FIFO (First In First Out) ordering. | It guarantees the FIFO order for the messages using sessions. |
| It does not support sessions. | It supports messaging-level sessions. |
| It comes with the support for the “At Least Once delivery” model. | This supports “At least once”, “At most once” and “Exactly once” delivery models for the messages. |
| It is not able to detect duplicate messages automatically. | It helps in detecting duplicate messages automatically. |
| It does not show support for dead lettering. | It comes with the support for dead lettering. |
| It supports the message of size 64KB. | It supports the message of size 256KB. |
| It comes with the support for one-to-one delivery of messages. | It comes with the support for both one-to-one and one-to-many deliveries of messages. |
| It does not support the transaction. | It supports the transaction. |
| It comes with the support for only batch receive. | It comes with supports for both batch send and batch receive of messages. |
| The receiving messages show non-blocking behavior. | The message behavior can be either blocking or non-blocking according to the configuration. |
29. Explain the Availability Set.
Availability Set is a logical grouping of VMs allowing Azure cloud to understand how the application ensures availability and redundancy.
Azure assigns each VM two types of domains in the availability set.
Fault Domain: It is the grouping of VMs sharing a common power source and network switch. The VMs in the availability sets are separated across up to 3 fault domains by default, helping the applications to be available by eliminating the impacts of network outages, power interruptions, and certain hardware failures.
Update Domain: It is the grouping of VMs and the underlying hardware that can be rebooted simultaneously. You can reboot only one update domain at a time, however, the order of reboot does not proceed sequentially. Before you start the maintenance of another update domain, the previously rebooted domain is provided with a recovery time of 30 minutes, ensuring that the domain is up.
Azure ensures flexibility by configuring up to 3 fault domains and 20 update domains for an availability set.
30. What feature of Azure do you use for stopping the issue of high load on the application with no man support on the flow?
You can stop this issue using VM Scale sets by defining proper configuration and conditions to provision a new VM when the application’s load increases.
Azure VM Scale Sets allows the developer to create and manage a group of load-balanced VMs. The scale sets need to be configured so that the count of VMs can automatically increase or decrease depending on the application demand.
Scale Sets ensure the high availability of the applications and allows the developers to manage, update, and configure large VMs centrally.
Azure scale sets are capable of supporting up to 1,000 VMs. If you create and upload the custom VM images, then the limit is 600 VMs.
31. Why is Azure’s active directory used?
Azure Active Directory is an Identity and Access Management system that helps in providing access to your employees for using specific products and services in your network. For example, Salesforce.com, Twitter, etc. Azure AD comes with in-built support for applications in its gallery which can be added directly.
32. Explain Azure service fabric.
Azure Service Fabric is a distributed systems platform that helps in packaging, deploying, and managing scalable microservices. Service Fabric offers solutions for the significant challenges in developing and managing cloud applications. It helps developers and administrators in avoiding complex infrastructure problems and focusing mainly on implementing complex, scalable, reliable, and demanding workloads. Service Fabric is a next-generation middleware platform that allows you to build and manage these enterprise-class, tier-1, cloud-scalable applications.
33. Explain stateless and stateful microservices for Service Fabric.
Service Fabric allows you to build applications that consist of microservices.
Stateless microservices (for example protocol gateways, web proxies), do not maintain a mutable state outside a request and its response from the service. The worker role of the Azure Cloud Services is an example of a stateless service.
Stateful microservices (eg. user accounts, databases, shopping carts, and queues) maintain a mutable, authoritative state outside the request and its response. Nowadays the Internet-scale applications come as a combination of both stateless and stateful microservices.
34. Can you add an existing VM to an availability set?
No, you cannot add an existing VM to an availability set. For adding a VM to a specific availability set, you need to create a VM in that set. There is no proven and experimented way for adding a VM to the availability set after it has been created.
35. Explain the break-fix issue.
Technical problems are considered as the break-fix issue. It is an industrial term that refers to the work done while supporting a technology when it fails while working normally and requires manual support work from the IT team for restoring the working of the technology.
36. How does a Character Analytics API work?
The character Analytics API does not provide the work characterization as good or bad. It uses the advanced feature that helps in mediating the processing of natural language.
37. What should be done in case of service failure?
You can perform the following steps in case of service failure.
Make sure that the objects services are stopped enabling the object services to withstand the occurred failure.
To complete the pending work you can make the system object storage remain functional by making the machine get back online again. After the machine has been started, the online replication will get activated instantly with the missing updated files.
If you are not able to replace the drive then remove the drive and let the system stay not mounted.
38. Explain csrun.
Csrun is a command-line tool that helps in deploying the packaged application to the Windows Azure compute emulator and managing the running services.
39. Explain the concept of the table in Windows Azure.
The tables in Windows Azure are used for storing information.
Tables help in storing structured data.
You can have zero to n number of tables in the storage account.
Each element has an essential key and its properties as a key-value pair.
40. Explain the use of Lookup transformation.
It is used to perform the lookups by combining the required data in the input columns along with the column present in the reference dataset. The reference table can be a new table, existing table, view, or use the SQL query for creating a reference table accordingly.
41. Do scale sets support data disks?
Yes, scale sets can define the attached data disk configurations that can be easily applied to all the virtual machines available in that set. Also, you can use the below-mentioned options for storing the data:
OS drives.
Temp drive but is not supported by Azure.
Azure data drive like Azure Blob, Azure tables.
External data drive like a remote database.
42. Can you get a public DNS or IP address for the Azure Internal Load Balancer?
No, Azure internal load balancers only support the private IP address. It does not allow you to assign external or public IP addresses and DNS names.
43. What would happen when the maximum failed attempts are reached during the process of Azure ID Authentication?
In that case, the account will get locked and the locking method will depend on the protocol that analyzes the provided password and IP address that is trying to log in.
44. Can you log in to a Linux Virtual Machine without using a password?
Yes, it is possible. For this, you need to use the key vault mapping to the desired Admin VM. It allows you to enter into another VM without entering the password for it.
45. Explain NSG (Network Security Group).
NSG stands for the Network Security Group that consists of Access Control List rules that help in either allowing or denying the network traffic to the subnet or the NICs (Network Interface Card) that is connected to the subnet or both. If you connect an NSG to a subnet then the rules are being applied to all the VMs in that subnet.
46. Explain Azure SLA.
The Azure SLA is a contract that ensures that if there are more than two role instances of a role deployed on Azure, access to that cloud service is guaranteed for at least 99.95% of the time.
It also ensures that if the role instance process is not running, then such processes are detected and required action will be taken 99.9% of the time.
If the mentioned points in the contract are not satisfied, then Azure has to provide a percentage of monthly fees to us according to the pricing model of the respective Azure services.
47. How can we use the on-premises application with Azure?
Azure AD provides an easy and secure way for connecting to the web-based applications that you choose. You will be able to access these applications in the same manner as you access your SaaS applications in Azure AD. There is no need for a VPN to make the changes to your network infrastructure.
48. Explain VNet.
It is considered to be a representation of your network in the cloud. It helps in logically isolating the instances that have been launched in the cloud from other resources of yours.
49. What are the scale limits for customers using the managed disks?
Using the managed disks will eliminate the limits that are being associated with the storage accounts. However, for a single subscription, the limit on the managed disks is 2000 by default.
50. Mention various power states of a Virtual Machine.
Below are various power states of a Virtual Machine.
- Starting specifies that the VM has been started.
- Running VM is in the running phase.
- Stopping specifies that the VM is being stopped.
- Stopped specifies that the VM is stopped.
- Deallocating specifies that the VM is being deallocated.
- Deallocated specifies that the VM is completely removed from the hypervisor but still available in the control plane.
Conclusion
So these were some of the most commonly asked Microsoft Azure interview questions that can help you crack Azure interviews. Once you learn the basic concepts and how to troubleshoot the issues then you can go for certification for better job opportunities. Also, it will increase your chances to get selected. So start learning and sharpen your skills.