Introduction  Azure Networking Interview Questions and Answers

Set up yourself for your upcoming Azure interview with the comprehensive guide on Azure Networking provided by us. Welcome to  this blog where we will give you elaborative information on the top 18 Azure Networking Interview Questions and Answers. 

Azure Networking, a demanding component of Microsoft’s Azure cloud computing platform, offers a wide array of networking capabilities designed to connect, protect, and deliver applications within Azure, across on-premises environments,and even other clouds.With the acceleration in the demand for cloud services, understanding Azure Networking has become an eminent need for IT professionals.

Azure Networking is renowned for its advanced level of flexibility, security, and scalability. It provides a wide horizon of services such as Virtual Networks (VNet),  load Balancers, VPN Gateway, Application, Content Delivery Network (CDN), Azure DNS, Traffic Manager, and many more. The services are designed in such a way that it ensures seamless connectivity, secure data transmission, and efficient routing of traffic, making Azure Networking an extensive solution for modern network management needs.

Top 18 Azure Networking Interview Questions and Answers

Q1.  Explain the role of Network Security Groups (NSGs) in Azure Networking?

Ans.  Network Security Groups (NSGs) in Azure Networking are decisive for controlling inbound and outbound traffic to  resources like VMs and subnets. They work as a farewell, providing layer-4 security by allowing or denying network traffic based on rules defined. Each NSG contains multiple security rules that dictate the allowed or denied traffic.

Q2.  Describe a situation where you had to arrange User Defined Routes (UDR) in Azure.

Ans.   In a project which involves Azure Virtual Networks, I had to configure User Defined Routes (UDR) for traffic management.  The outline of the situation involved multiple subnets within the same VNet, each hosting various services.  To ensure that traffic between the subnets was routed through a Network Virtual Appliance (NVA), UDRs are necessary. I will create a route table and add routes which will specify the NVA as the next hop. Each route corresponds to a specific subnet’s address range. After setting up the UDRs , I associated them with their respective subnets. This reassures all traffic destined for those subnets would be directed via the NVA, which enables us to implement custom network controls.

Q3. How to ensure secure communication between Azure and on-premises servers?

Ans.  To ensure secure communication between Azure and on-premises servers, one can use a Site-to-Site VPN or ExpressRoute. A Site-to-Site VPN creates an IPsec/IKE (Internet Protocol Security/ Internet Key Exchange) tunnel from the on-premise VPN device to the Azure VPN Gateway. Hence this provides encryption of data in transit, ensuring its confidentiality.

ExpressRoute is another option that authorises a private connection from one’s on-premises network to Azure’s network.  It doesn’t go over the public internet, which provides better reliability, faster speeds, lower latencies, and higher security than typical connections. Alin with these, Network Security Groups (NSGs) can be used to control inbound and outbound traffic to resources within a Virtual Network (VNet), which further enhances security.

Q4. What is the role of Azure Front Door In Azure Networking?

Ans . Azure Front Door is scalable and it secures entry point for fast delivery of global applications.Besides it facilitates the routing of client requests for the fastest and most available backend, based on health probes. The service adds to the performance by using split TCP-based anycast protocol and Microsoft’s global network. The Azure Front Door also provides SSL offload, path-based routing, session affinity, URL rewrite, and custom domains with SSL.

Q5. How would one troubleshoot a VPN Gateway that is not connecting in Azure?

Ans. To troubleshoot a non-connecting VPN Gateway in Azure, I will first check the gateway’s health status using Azure Network Watcher. If it shows unhealthy, I’ll investigate further by checking for any configuration errors and inconsistencies. Further, I’ll verify the IPsec/ IKE parameters match between Azure and on-premises VPN devices. Mismatched settings hence cause connection issues.I’ll also use Azure Monitor to review metrics and logs related to the VPN Gateway. This provides insights into traffic patterns and potential anomalies causing the issue. Furthermore, I’ll examine the associated Network Security Group (NSG) rules to ensure these are not blocking necessary traffic.

Q6. Explain the differences between Azure Load Balancer and Azure Traffic Manager ?

Ans. Azure Load Balancer and Azure Traffic MAnager are both used for distributing network traffic, but they act at different levels and serve different purposes.

Azure Load Balancer is a Layer-4 (TCP, UDP) type balancer that provides high availability by distributing incoming traffic among healthy service instances in cloud services or virtual machines within a data centre.

On the other hand, Azure Traffic Manager is a DNS-based traffic load balancer that operates at the application level (Layer 7). It distributes traffic to globally distribute endpoints based on various routing methods like performance, priority, or geographic proximity.

Q7. Can you discuss the importance of ExpressRoute in Azure Networking?

Ans. ExpressRoute is an eminent component in Azure Networking, which provides private connections between Microsoft data centres and infrastructure on your premises or in a colocation environment. It provides higher security, reliability, speeds, lower latencies, and consistent network performance compared to basic internet-based connections. ExpressRoute connections do not go over the public Internet, which makes it ideal for sensitive workloads, regulate compliance requirements, and transfer large amounts of data cost-effectively.

Q8. How do you implement redundancy in Azure Networking?

Ans. Redundancy in Azure Networking is achieved through various strategies. One of the methods involves deploying multiple instances of an application across multiple regions, known as geo-redundancy, which ensures that if one region fails, the application remains accessible from another region. Another strategy that comes in is to use Azure Traffic Manager which directs incoming traffic to the most appropriate endpoints. Thus it provides automatic failover when an endpoint goes down. 

Azure Load Balancer is also used for redundancy. It distributes network traffic across various servers to ensure no single server becomes a point of failure.

Q9.  How would you design a hybrid network architecture using Azure and why?

Ans. A hybrid network architecture using Azure would involve integrating on-premises infrastructure with Azure’s cloud services. The design begins with establishing a secure connection between the local network and Azure via VPN or ExpressRoute, depending on bandwidth requirements and sensitivity of data. Azure Virtual Network  (VNet) is then set up to host cloud resources securely. Subnets are hence created with VNet for segregation of resources based on their roles. Network Security Groups (NSGs) are thus applied at subnet level for granular control over traffic flow.

Q10. How would you ensure data compliance and maintain network performance in a geographically dispersed Azure network?

Ans. To ensure data compliance and maintain network performance in a geographically dispersed Azure network, I will implement several strategies. In the first place I’ll use Azure Policy to enforce organisational standards and assess compliance at scale. This tool hence allows for the creation of policy definitions which describe what is allowed or disallowed within the network. Secondly , I’ll utilise Azure Traffic Manager for DNS- based traffic load balancing to distribute traffic optimally to services across global Azure regions besides providing high availability and responsiveness. In the third place, I’ll leverage Azure Front Door Service for application acceleration through split TCP- based anycast protocol and Microsoft’s global network infrastructure. Thus it provides SSL offload and end-to-end encryption for securing data in transit. Finally, I’ll employ Azure ExpressRoute for private connections between Azure data centres and infrastructures on-premises or in a colocation environment. This bypasses the public internet, besides ensuring higher security, reliability, and lower latencies.

Q11. Can you discuss some of the limitations you’ve encountered with Azure Networking and how you resolved or worked around them?

Ans. As in my experience with Azure Networking, I’ve encountered a few limitations. One of them was the inability to change or modify the address space of a virtual network post creation. To resolve this, I deleted and recreated the VNet with the desired address space.

Another limitation which I encountered was the restriction on the number of Network Security Groups (NSGs) rules – 1000 per NSG. When I  exceeded the limit, I worked around it by consolidating similar rules and removing redundant ones.

Besides I also faced issues with peering between VNets across different subscriptions. The workaround for this was the use VPN Gateways instead of VNet peering. In conclusion, there’s no built-in redundancy for ExpressRoute circuits. To mitigate this, I substituted dual circuits in an active configuration for high availability.

Q12.  Explain how Azure DNS works and how it fits into Azure’s networking infrastructure.

Ans. Azure DNS is a hosting service for domain name system (DNS) domains, providing name resolution using Microsoft Azure infrastructure. It translates more easily memorised domain names to the numerical IP addresses which are needed for locating and identifying computer services and devices. In Azure’s networking infrastructure, Azure DNS plays an eminent role in managing and resolving domain names. When an application or service within Azure needs to reach another resource, it hence uses Azure DNS to resolve the domain name into an IP address, this process thus ensures seamless communication between different resources within the Azure ecosystem.

Q13. Discuss a challenging Azure Network deployment you managed and how you ensured its success.

Ans. Lately, in a project, I managed an Azure Network deployment involving the integration of various virtual networks over different regions. The challenge was to ensure seamless connectivity and data transfer with least latency.The very first step involved designing a robust network architecture. This includes creating Virtual Networks (VNet) in every region and setting up VNet peering for inter-region communication. To minimise the latency, we used Azure’s Global VNet peering feature which provides low-latency, higher-bandwidth connections between VNets. Further, we implemented Network Security Groups (NSGs) to control inbound and outbound traffic to the services. We also utilised Azure Firewall for advanced threat protection and to maintain centralised network access control. To audit network performance and troubleshoot issues, we leveraged Azure Monitor and Network Watcher. These tools hence provided insights into our network performance and helped identify bottlenecks. In conclusion, we conducted rigorous testing before going live. This includes load testing to ensure our network could handle expected traffic volumes and failover testing to validate the disaster recovery plans.

Q14. Can you explain how you would implement zero-trust network security in Azure?

Ans. Zero-trust network security in Azure is implemented through a consolidation of identity and access management, multi-factor authentication (MFA), least privilege access, micro-segmentation, and continuous monitoring. Identify and Access Management ensures only verified users can access resources. It adds an extra layer of security by requiring additional verification methods. Least privilege access restricts user’s access rights to the minimum necessary for their role, reducing potential attack vectors. Continuous monitoring allows real-time threat detection and response. Azure provides tools like Azure Active Directory for IAM and MFA, Azure Policy for enforcing least privileges, Azure Firewall for micro-segmentation, and Azure Security Center for continuous monitoring.

Q15. How would you set up Network Watcher for monitoring purposes in Azure?

Ans. To set up Network Watcher for monitoring in Azure, start by enabling it in your subscription. Navigate to the Azure portal and choose ‘Network Watcher’ from the left-hand menu. Click on ‘Regions’, further select the region you want to monitor. Select ‘Enable Network Watcher’. Once enabled, use the ‘Topology’ feature to visualise network resources and their dependencies. For further packet capture, direct to the VM of interest, click on ‘Packet Capture’, then ‘Add’. Entitle parameters like storage location, maximum bytes per packet, etc., and start capturing. For NSG flow logs, go to the relevant NSG, click on ‘Flow Logs’, then ‘On’. Select a storage account or Event Hub for lg destination. Set traffic analytics status to ‘On’ for insights into traffic patterns.

Q16. How do you ensure that your Azure network is scalable and yet cost-effective?

Ans. To ensure scalability and cost-effectiveness in Azure networking, you should implement a few basic strategies. Firstly, use Virtual Network (VNet) peering for interconnecting VNets, which allows resources to communicate across VNets, which reduces costs associated with bandwidth. Secondly, utilise Azure Load Balancer or Application Gateway for distributing network traffic efficiently, enhancing application performance besides minimising latency and costs. In the third place, consider using Azure Traffic Manager for DNS- based traffic load balancing; it directs client requests to the nearest data centre improving speed and availability. In the fourth place, leverage Azure CDN to cache content at strategic locations for faster delivery and reduced bandwidth consumption. At the last, regularly monitor and analyse network usage with tools like Network Watcher and Cost Management + Billing to identify potential cost saving opportunities.

Q17. Explain the significance of Private Link service in Azure?

Ans. Private Link service in Azure is an eminent component for secure and private data connection. Thus it enables access to services over a private endpoint in your virtual network, eliminating exposure to the public internet. This reduces risk of data leakage and enhances security by preventing potential attacks from the internet. Hence this reduces risk of data leakage and enhances security by preventing potential attacks from the internet. Private links also ensure that traffic between your virtual network and the service travels Microsoft’s backbone network, which provides reliable connectivity. Further, it allows you to manage data compliance requirements by keeping data within a specific region.

Q18. Can you discuss the process of migrating a traditional network architecture to Azure Networking?

Ans. Migrating a traditional network infrastructure to Azure Networking involves several steps. Firstly, assess the current network setup and identify components that can be migrated or replaced with Azure services. This includes servers, routers, firewalls, etc. Next, design an Azure Network infrastructure that mirrors your existing setup as closely as possible. Use Virtual Networks (VNet) for isolation, Network SEcurity Groups (NSGs) for security, and VPN Gateway for connectivity.

Once designed, implement the new Azure Network. Begin with creating VNets and subnets, then configure NSGs and routing tables. Further, establish connectivity between on-premises networks and Azure using VPN Gateway or ExpressRoute. Later, migrate applications and data to Azure. This could involve moving VMs, databases, and other resources. Ensure all dependencies are accounted for during migration. Test each component thoroughly after migration to ensure functionality and performance. Concludingly, monitor and manage the Azure Network. Use tools like Network Watcher and Traffic Analytics for visibility into network performance and security. View and update configuration regularly as needed based on monitoring insights.

Conclusion:

The aforementioned questions and answers cover a wide horizon of Azure Networking concepts and it must help the ones prepare thoroughly for the upcoming interview. Make sure to delve deeper into each topic to determine an illustrative understanding during the interview.