Understanding Azure Dedicated Host

This article explains the basics of Azure dedicated host – what it is, when it is useful and advantages and use cases for when it will be useful.

What is Azure's dedicated host?

When we create a virtual machine in Azure, these virtual machines are created on an underlying physical host in the Azure data center. Azure also gives you the capability of assigning this entire physical host as a resource to you. So, when we create a resource based on the dedicated host, Azure allocates the entire underlying physical host itself.

When is this service useful?

If a company wants to have their own dedicated physical host on which they can go and launch the VMs, that case dedicated host will be useful.

What are the advantages of having a dedicated physical host?

Hardware Isolation

We can go ahead and launch VMs on the underlying physical host, and no other customer/user can create their own VMs into this physical host.

Control over maintenance event

Another advantage is that we can control the underlying maintenance events on the server. If there is a maintenance event that needs to be carried out by Azure on the underlying physical host because the physical host is still going to be in the Azure data center, it's only that has been given to us. So, if a maintenance event needs to be performed on that physical host, we can control when the maintenance event will take place. This is very important for large organizations if they have applications running on VMs that are located on the physical host and if the underlying maintenance event is going that may cause an outage, then the user can decide on the timeframe on when that maintenance event can take place. Otherwise, on a normal physical host users do not have control over the exact timeframe of those maintenance events.

Creating Azure dedicated host

Now in Azure, choose dedicated host and create. Select resource group, Instance Name, create host group, size family….

Let’s click on review and create now….

Boom! We can see that “Validation failed. Required information is missing or not valid.” Let’s go back to the Basics tab to see what’s the error there.

From the error message, we can see that for this family type of VMs, we need to have at least 96 virtual CPUs allocated to the subscription. So, this is meant for large organizations where the requirements of VMs are more. In my case, it’s just 20 vCPUs that support my subscription in this region.

Hope you understood the use case of Azure dedicated host.

Happy Learning!