For those that have
never used Azure before, or need a refresher on some of the great things you
can do, in both, the Azure Portal, and from the command line, here are couple of
short modules in the new Microsoft Learn site:
https://docs.microsoft.com/learn/modules/tour-azure-services-and-features/
I encourage everyone
that uses Azure to learn how to use the command line tools. For the longest
time I avoided the CLI as I like the way the Portal allows you to discover new
features through exploration, which has always been the advantage of a graphical
user interface over the command line. Yet the strength of learning the command
line tools is how fast you can get tasks accomplished as well as the ability to
automate tasks with scripts.
Microsoft Learn has
a module to learn about automating Azure tasks here https://docs.microsoft.com/learn/modules/automate-azure-tasks-with-powershell/
In order to
understand the value of containers I believe it is important to know how we (as
an industry) got to this point. I find that understanding the history of
technology helps to explain the current situation. (It also makes it easier to
extrapolate out potential futures.) From the perspective of server
technologies, and hosting applications with an intention to scale them,
virtualization, and virtual machines have been a standard mechanism for the
longest time. If you have never used a VM (virtual machine) you can get some
perspective from following this lab and setting up a VM.
https://docs.microsoft.com/en-us/learn/modules/welcome-to-azure/
A Virtual Machine
abstracts the physical hardware upon which it runs. When you deploy an
application to a VM you should not care what the actual hardware is. Often a
physical server can be running multiple virtual machines, and this provides a
higher level of potential resource utilization. Considering that data canters
are starting to become a noticeable consumer of world power supplies, it should
be obvious that the more energy efficient we can be with our servers the better
we are conserving our global resources. Yes, virtualization might be
economically efficient, and it could be considered ecological more efficient
than running everything on physical hardware. A virtual machine will host an
operating system, and the software you deploy will need to run on that operating system. Virtual Machine technology is
what enables most of the worlds big Cloud providers to work. For a high level
understanding of how Azure works this video provides a good overview
A container provides a host to run a software application that
abstracts another level of concern away from the deployment. While Virtual
Machines provide an abstraction from the physical hardware, containers provide
an abstraction from the operating system.
By being abstracted
from the OS (operating system), there is no longer a need to be concerned about
the setup of the OS, how it hosts your application, where it has your
application installed, and numerous other issues. This enables a more agile
approach to be taken when deploying applications. An application running in a
container can be easily moved from one location to another, simply move the
container and everything you need will come with it.
Containers also
enable an even greater level of resource (energy) efficiency. When an
application is hosted in a virtual machine, then you scale the application by
creating copies of that virtual machine (scale out), or adding more computer
resources to the virtual machine (scale up). The virtual machine is the unit of
scaling. With a container, the unit of scaling is closer to the application,
you scale out your application by creating more instances of your container. As
a virtual machine can host multiple container instances you are going to be
getting more from the potential resources than if you only have the application
running once per virtual machine.
Containers are not
limited to specific types of application, or programming language either. Most
common languages and types of app can be containerized. A container can run on
a local machine, your laptop, a big data canter server, or an IOT device. This
means you can build and test containers locally and then deploy them to scale
with the confidence they will work the same way.
One of the most
popular container runtimes is called Docker. Docker provides container
compatibility between Mac, Windows, and Linux machines. Using Docker, an
application can be deployed to a local container, tested and then the container
image can be deployed to scale by creating multiple instances of that container
image on devices anywhere you desire (as long as it supports Docker).
When you create a
container (or Docker) image you are defining the contents of the container, You
might consider it a template definition of what the container will be running.
If you are a programmer then think about a container image as a class definition.
A container instance is a running version of the container image. Using the
programming metaphor again, the instance would be an object instantiated from
the image (class).
In order to manage
your containers and make best use of the
resources you will want to perform tasks such as scheduling, monitoring,
scaling, connectivity (networking), upgrades, and failure management. This is
where Kubernetes comes into play. Kubernetes is an orchestration tools for
containers. This means Docker and Kubernetes work together to deliver a
great container experience.
To understand the
basics of Containers and Kubernetes watch this video on Channel 9.
If you want to setup
Kubernetes on a machine (or virtual machine) there is a fair amount of work
that needs to be done, you need to set up routing tables, storage to support
your applications, etc… The great thing about using Kubernetes in Azure is the setup is all managed for you.
There is a tutorial that you can follow to get a simple website running in a Docker
container and then use AKS (Azure Kubernetes Service) to deploy and orchestrate
the containers. It should take you around an hour to complete and should help
you to better understand how Docker and Kubernetes work together using Azure
services.
If you do not need
the orchestration provided by Kubernetes and simply want a container running
your app in the Cloud the Azure Container Instances (ACI) simplifies the setup
process even further. You can think of the ACI service as providing 'serverless'
containers. You do not need to care about managing servers at all. This
tutorial will help you understand how to use Azure Container Instances
If you want to find
out more about how to get the most from containers in your organization get in touch and we can organize a workshop or training session for you and your team.
