20 Azure Service Bus Interview Questions and Answers

Azure Service Bus is a cloud messaging system that helps businesses connect applications and services. It is a popular tool for developers and is often used in conjunction with other Azure services. When interviewing for a position that uses Azure Service Bus, it is important to be prepared to answer questions about the tool. In this article, we review some of the most common Azure Service Bus interview questions and provide tips on how to answer them.

Azure Service Bus Interview Questions and Answers

Here are 20 commonly asked Azure Service Bus interview questions and answers to prepare you for your interview:

1. What is Azure Service Bus?

Azure Service Bus is a cloud-based messaging system that helps you build applications that need to communicate with each other. It can be used to send messages between applications or between different parts of the same application. Service Bus can also be used to connect on-premises applications with cloud-based applications.

2. What are the main components of Azure Service Bus?

The main components of Azure Service Bus are the message queues, topics, and subscriptions. Message queues are used to store messages that need to be processed by a service. Topics are used to group together related messages, and subscriptions are used to specify which messages a particular service should receive.

3. How do you design an ideal architecture for a large scale event driven application on Azure Service Bus?

There are a few key things to consider when designing a large scale event driven application on Azure Service Bus:

1. Make sure to use partitions to scale out the number of concurrent readers and writers.
2. Use a message filter to ensure that only relevant messages are processed by each consumer.
3. Use a dead letter queue to store messages that cannot be processed successfully.

By following these guidelines, you can ensure that your application can scale to meet the needs of a large number of users.

4. Can you explain how to create topics and subscriptions with Azure Service Bus?

You can create a new topic by using the Azure portal, Azure CLI, or Azure PowerShell. You can then create subscriptions to that topic by using the Azure portal, Azure CLI, Azure PowerShell, or the Azure Service Bus Explorer tool.

5. How can you implement message retry handling with Azure Service Bus?

Azure Service Bus provides a message retry policy that can be configured to automatically retry messages that fail due to transient errors. This can be configured on a per-queue basis, and will automatically retry messages that fail with certain error codes.

6. What’s the difference between service bus queues, virtual machines, and web apps in context of hosting a worker role in Azure?

Service bus queues are used for message passing between applications. Virtual machines can be used to host applications, and web apps can be used to host web sites.

7. Why would you use Azure Service Bus instead of another cloud messaging system like AWS SQS or RabbitMQ?

Azure Service Bus is a cloud messaging system that is designed to provide reliable, secure, and scalable messaging capabilities. It supports a variety of messaging scenarios, including one-way messaging, request/response messaging, and publish/subscribe messaging. Azure Service Bus is also highly scalable and can handle large numbers of messages.

8. What happens if you send messages faster than they can be processed by the consumer?

If you send messages faster than they can be processed, then the messages will be queued up and processed as soon as the consumer is able to.

9. Is it possible to have multiple listeners subscribing to the same topic in Azure Service Bus? If yes, then how?

Yes, it is possible to have multiple listeners subscribing to the same topic in Azure Service Bus. This can be accomplished by using the Azure Service Bus Topics feature, which allows for multiple subscribers to receive messages from the same topic.

10. Is it possible to debug Azure Service Bus locally? If yes, then how?

Yes, it is possible to debug Azure Service Bus locally. You can do this by setting breakpoints in your code and then attaching the debugger to the Azure Service Bus process.

11. What happens if your business logic throws an exception after processing a message from Azure Service Bus?

The message will be placed back on the queue to be processed again.

12. What does reliability mean when working with Azure Service Bus?

Reliability in Azure Service Bus means that messages are delivered exactly once, and in the order that they were sent. This is accomplished through a combination of features like message sessions, message locking, and message queuing.

13. What is the difference between auto-delete and deferred deletion modes when deleting a subscription?

The main difference between these two modes is that auto-delete mode will delete the subscription as soon as all of the messages in it have been processed, while deferred deletion mode will keep the subscription around until it is explicitly deleted. This can be useful if you want to ensure that all messages in a subscription are processed before it is deleted.

14. How does Azure Service Bus support scalability?

Azure Service Bus supports scalability in a few ways. First, it can automatically scale up or down based on demand. This means that if you have a sudden spike in traffic, Azure Service Bus can automatically scale to meet the demand. Second, Azure Service Bus can be deployed across multiple regions, so that if one region becomes overloaded, traffic can be routed to another region. Finally, Azure Service Bus supports partitioning, so that messages can be spread across multiple servers for even further scalability.

15. What are some limitations that you should be aware of when using Azure Service Bus?

There are a few potential limitations that you should be aware of when using Azure Service Bus. First, Azure Service Bus is a cloud-based service, so you will need to have an internet connection in order to use it. Additionally, Azure Service Bus is a paid service, so you will need to sign up for an account and pay for the service in order to use it. Finally, Azure Service Bus has a limit on the number of messages that can be sent through the service per day, so if you are expecting to send a large number of messages, you may need to plan accordingly.

16. When is the best time to start thinking about scaling up your application hosted on Azure Service Bus?

The best time to start thinking about scaling up your application hosted on Azure Service Bus is when you start to see performance degradation or when you start to see errors being returned from the Azure Service Bus. If you wait until your application is completely down, then it will be too late to scale up and you will have to start from scratch.

17. What is the significance of partitioning in Azure Service Bus?

Partitioning in Azure Service Bus is used to improve the scalability and performance of message processing by distributing the load across multiple message processors. By partitioning the message stream, each message processor can handle a smaller subset of the messages, which reduces the overall processing time. In addition, partitioning can also improve the availability of message processing by allowing for message processors to be taken offline for maintenance without affecting the overall message processing.

18. How will you know if your workload requires partitioning?

Partitioning is a way of scaling out a workload by breaking it into smaller pieces that can be processed in parallel. If your workload is starting to become too large or slow to process in a single instance, then partitioning may be a good option to consider. There are a few different ways to partition data, so you will need to evaluate your specific workload to determine the best approach.

19. How is rebalancing performed in Azure Service Bus?

Rebalancing in Azure Service Bus is the process of distributing the load of messages across multiple servers in order to improve performance and ensure availability. This is done by dividing the message queue into multiple partitions and then distributing those partitions across the servers.

20. What are some common errors seen while creating partitions and what can you do to avoid them?

Some common errors seen while creating partitions include:

– Not specifying the correct number of partitions: You need to make sure that you specify the correct number of partitions when you create them. Otherwise, you may end up with too few or too many partitions, which can cause problems.
– Not specifying the correct partition size: Partitions need to be of a certain size in order to function properly. If you create partitions that are too small, they may not be able to handle the load, and if you create partitions that are too large, they may be inefficient.
– Not specifying the correct partition key: The partition key is what determines which messages go to which partition. If you don’t specify the correct partition key, the messages may not be distributed evenly, which can cause problems.