Migrate IIS Web Apps to Azure App Service.
Now I'm presuming that you know what an IIS web app is and that
you're familiar working with IIS on Windows Server. You may not be
as familiar with Azure App Service.
What is it?
Well,
it's a Platform as a Service, or PaaS, product in which a lot of
the underlying compute is abstracted away.
Think of what you've got going on on‑premises. You have
one or more IIS web server machines, physical or virtual,
it doesn't matter, probably behind a load balancer or using the network load
balancing service that's built into Windows Server, probably have a SQL Server
back end, and now you're tasked with rehosting those workloads up into Azure,
and maybe you don't have a site‑to‑site virtual private network or an
ExpressRoute link. What can you do?
Well, the App Service is fantastic.
It's a hosted web application, API application
platform, and it's got a lot going for it.
The agility,
the ability to auto scale with no load balancer is
a great benefit of App Service.
It eases your administration, and the idea, the business idea for Microsoft, is
that App Service allows your developers to focus more on the application and
serving your customers as opposed to worrying about all of the optimizations
and stuff that you need to do on‑premises.
Now there's a place at the table for your infrastructure engineers. The
App Service plan is the underlying compute. And in stark contrast to
when you're running your IIS on a Windows Server VM in Azure, when you
have full control of the entire VM,
the App Service plan is a much more abstracted Platform as a Service
offering where you have some degree of control,
for example,
you can resize to provide more or less relative compute, and
you can do those autoscaling rules and so on,
but you're not going to have full stack access.
That's one of the tradeoffs that we always have when we're thinking
between Infrastructure as a Service on one hand,
Platform as a Service on the other.
Now,
it's beyond our scope for this training because Microsoft puts all of
the Azure data products in entirely different certifications. I would
encourage you to look at the DP exams and also the Azure Architect
AZ‑300 series exams. But I want you to know that Azure Migrate has a
database migration path.
So in summary,
in this course, we're concerned only with taking the IIS web
application, and then we would separately use Azure Migrate tools
to assess and migrate the databases into a Platform as a Service
orientation. For example,
like in this diagram, running your Azure SQL databases under an Azure SQL database virtual server in Azure.