Chapter 7: Designing Compute Solutions

In the previous chapter, we looked at how to secure our Azure applications using key vaults, security principals, and managed identities.

When building solutions in Azure many components use some form of compute – such as a virtual machine (VM). However, there are many different types of compute, each with its own strengths. Therefore, in this chapter, we focus on the different types of compute services we have available to us and which options are best suited to which scenarios.

We will then maintain the security and health of VMs by ensuring they are always up to date with the latest OS patches.

Finally, we'll look at containerization and how we can use Azure Kubernetes Service (AKS).

With this in mind, we will be covering the following topics:

• Understanding different types of compute
• Automating virtual machine management
• Architecting for containerization and Kubernetes

Technical requirements

This chapter will use the Azure portal (https://portal.azure.com) for examples.

Understanding different types of compute

When we architect solutions, there will often be at least one component that needs to host, or run, an application. The application could be built specifically for the task or an off-the-shelf package bought from a vendor.

Azure provides several compute services for hosting your application; each type can be grouped into one of three kinds of hosting model:

• Infrastructure as a Service (IaaS): VMs are within this category and support services such as storage (that is, disk drives) and networking. IaaS is the closest to a traditional on-premise environment, except Microsoft manages the underlying infrastructure, including hardware and the host operating system. You are still responsible for maintaining the guest operating system, however, including patching, monitoring, anti-virus software, and so on.
• Platform as a Service (PaaS): Azure App Service is an example of a PaaS component. With PaaS, you do not need to worry about the operating...

Automating virtual machine management

Virtual machines are part of the IaaS family of components. One of the defining features of VMs in Azure is that you are responsible for keeping the OS up to date with the latest security patches.

In an on-premise environment, this could be achieved by manually configuring individual servers to apply updates as they become available; however, in many organizations, more control is required; such as, for example, the ability to have patches verified and approved before mass roll out to production systems, control when they happen, and control reboots when required.

Typically, this could be achieved using Windows Server Update Services (WSUS) and Configuration Manager, part of the Microsoft Endpoint Manager suite of products. However, these services require additional management and setup, which can be time-consuming.

As with most services, Azure helps simplify managing VM updates with a native Update Management service. Update Management uses...

Architecting for containerization and Kubernetes

This section will look in more detail at AKS, Microsoft's implementation of Kubernetes. To understand what AKS is, we need to take a small step back and understand containerization and Kubernetes itself.

Containerization

As we briefly mentioned earlier, containerization is a form of virtualization in that you can run multiple containers upon the same hardware, much like virtual machines. Unlike virtual machines, containers share the underlying OS of the host. This provides much greater efficiency and density. You can run many more containers upon the same hardware than you can run virtual machines because of the lower memory overhead of needing to run multiple copies of the OS – as we can see in the following diagram:

Figure 7.10 – Containers versus virtual machines

In addition to this efficiency, containers are portable. They can easily be moved from one host to another, and this is because containers are self...

Summary

This chapter looked at the different compute options available to us in Azure and looked at the strengths and weaknesses of each. With any solution, the choice of technology is dependent on your requirements and the skills of the teams who are building them.

We then looked at how to design update management processes to ensure any VMs we use as part of our solution are kept up to date with the latest security patches.

Finally, we looked at how we can use containerization in our solutions, and specifically how Azure Kubernetes Service provides a flexible and dynamic approach to running microservices.

In the next chapter, we will look at the different networking options in Azure, including load balancing for resilience and performance.

Exam scenario

The solutions to the exam scenarios can be found at the end of this book.

Mega Corp is planning a new multi-service solution to help the business manage expenses. The application development team has decided to break the solution into different services that communicate with each other.

End users will upload expense claims as a Word document to the system, and these documents must flow through to different approvers.

The HR department also wants to amend some of the workflows themselves as they can change often.

The application will have a web frontend, and the application developers are used to building .NET websites. However, they would like to start moving to a more containerized approach.

Suggest some compute components that would be suited to this solution.

Further reading

You can check out the following links for more information about the topics that were covered in this chapter:

• Azure Batch: https://docs.microsoft.com/en-us/azure/batch/
• Azure Functions: https://docs.microsoft.com/en-us/azure/azure-functions/
• Azure Service Fabric: https://docs.microsoft.com/en-us/azure/service-fabric/service-fabric-overview
• Azure Web Apps: https://azure.microsoft.com/en-gb/services/app-service/web/
• Azure Logic Apps: https://azure.microsoft.com/en-gb/services/logic-apps/
• Azure Kubernetes Service: https://azure.microsoft.com/en-gb/services/kubernetes-service/