(air whooshing)
(gentle music)
- Welcome to Azure Essentials.
I'm Matt McSpirit, and in the next few minutes,
I'll give you an overview
of Azure virtual machine scale sets,
a critical service for creating and dynamically managing
thousands of VMs in your environment.
Now if you are new to the service
this will get you up to speed,
or if you haven't looked at VM scale sets in a while
we'll show you how it has significantly evolved
to help you efficiently architect your apps
for centralized configuration,
high availability, auto-scaling and performance,
cost optimization, security, and more.
So, let's start by addressing
what is a Virtual Machine Scale Set in Azure?
Well as the name implies,
this Azure service lets you create and manage
a group of virtual machines to run your app or workload
and provides sophisticated load-balancing,
management, and automation.
VM Scale Sets lays the foundation
for centralized and consistent configuration
of VMs in your environment.
One of the primary functions
is to specify a VM template
with the characteristics that you need
for your apps and workloads to run reliably.
This includes: the VM image,
with support for Windows and Linux platform images
as well as your own custom images, the VM size,
your networking parameters,
the number of VM instances in the group,
and with virtual machine extensions
you can also add post-deployment configuration
like monitoring, anti-malware and automation.
As you set them up,
there are two management modes to deploy your scale sets:
Uniform Orchestration, which is optimized
for large stateless workloads
where your VM instances are identical.
Or the newer Flexible orchestration mode,
which adds more options:
from running workloads with different VM types;
or changing your VM sizes
without redeploying your scale set;
to architecting your scale sets for high availability.
And the good news is, they are all easy to set up.
You can define your Virtual Machine Scale Set
in the Azure Portal as you just saw
or with an Azure Resource Manager Template.
Of course, if you prefer
you can use scripting tools like Azure CLI,
PowerShell, and even infrastructure
as code tools like Terraform.
Once set up, any new VM added to the scale set
will inherit the configurations that you have defined.
And it's easy to make changes across your scale set.
For example, with image-based upgrades,
when a new version of a custom
or marketplace image is made available,
Virtual Machine Scale Sets
will detect that and start upgrading
the VM instances in batches,
and you can use protection policies
to exclude VMs that you don't want to upgrade.
Or another example of what you can do
is to upgrade your existing VMs in one-go
to take advantage of the latest and greatest VMs in Azure.
That said, beyond consistent configurations,
scale sets are used to distribute
your business-critical application
across multiple instances to provide high availability.
And this is achieved in a number of ways.
For example, you can automatically distribute
up to 1,000 VM instances
between availability zones in minutes.
This gives you utmost availability, up to 99.99%,
and helps you to mitigate
any possible datacenter wide issues.
Availability zones are offered in most geographies
and represent physically separate locations
in an Azure region composed of one or more datacenters
with independent power, cooling, and networking.
VMs can be automatically spread across
fault domains in a region,
or you can specify a fault domain
as part of your VM deployment,
which makes it easier to replace VMs.
Now this is especially relevant
for open-source databases like Cassandra
or other quorum-based applications.
Of course, you also have the option to replicate
your VM instances to another Azure region
for failover compute.
And for storage redundancy,
you can also back up data disks using Azure Backup.
Beyond hardware failure resilience measures,
to get ahead of issues before they impact your operations,
you can install the application health extension
on each VM instance,
so that your app or workload
can report application-specific health metrics to Azure.
And once you enable automatic instance repair,
Azure will automatically remove
and replace instances in an unhealthy state,
to maintain high availability.
As you architect for availability
with Azure VM Scale Sets
you can of course also scale your applications
on demand while increasing performance.
Scale sets integrate with Azure load balancer
for basic layer-four traffic distribution
and Azure Application Gateway
for more advanced layer-seven traffic distribution.
This helps you to easily spread
your incoming network traffic across the VMs
in your scale sets.
Which in turn helps you build scalable solutions
while maintaining high levels of performance.
You can also configure your VM scale set to auto-scale.
For example, if you're running an e-commerce site
you may need to scale your front end
in response to some event, like a holiday sales spike.
Azure will automatically add and subtract VM instances
in response to demand
so that there is no decline in your app
or workload experience.
Under scaling, you can use metric-based
auto-scaling rules and define thresholds
that trigger an increase in VM instances to scale out.
And likewise, you can set similar thresholds
for when to scale in,
taking into account a specified cool down period
which allows for a buffer of time
before the scale in action is triggered.
And of course, you can manually scale out
and in as you need to.
The ability to dynamically scale your VM pool
also brings numerous efficiencies
as you run your workloads on Azure,
because instead of pre-provisioning VMs
you're only paying for the compute resources
your application needs.
And for even more savings,
for your interruptible workloads,
you also have the flexibility of using Azure Spot VMs
that take advantage of spare compute capacity in Azure
as and when it's available.
You can also mix and match Azure Spot VMs
with regular on-demand VMs.
And if you're worried about Spot VM evictions,
the try to restore feature
in Azure Virtual Machine Scale Sets,
will automatically try to restore an evicted Spot VM
and maintain the target VM instance count
in your scale set.
In fact, we covered Spot VMs
as part of your cost optimization strategy,
in our last Essentials overview
which you can watch at aka.ms/EssentialsSpotVMs.
Next, Virtual Machine Scale Sets
help you improve the security posture of your applications
by keeping them up-to-date.
Upgrades can be performed automatically, in random order,
manually, or using rolling upgrades in defined batches.
In addition to image upgrades,
you can also do automatic VM guest patching
for critical and security updates,
and this helps to ease management by safely
and automatically patching virtual machines
to maintain security compliance.
Patch orchestration is managed by Azure
and updates are rolled out sequentially
across VMs in the scale set
to avoid application downtime.
You can also force updates on-demand.
And with Automatic Extension Upgrades,
critical updates are applied
as they become available from publishers.
So that was a quick overview
of Azure Virtual Machine Scale Sets
and how they can help you to create
and deploy thousands of VMs in minutes.
The metrics and template-based approach
helps you to consistently architect your apps
and workloads for auto-scaling,
availability, and performance,
giving you the control that you need.
This lets you focus on your app
instead of the complexities of managing your infrastructure.
And to learn more visit aka.ms/VMSSOverview
and keep watching Microsoft Mechanics
for more in the series, bye for now!
(gentle music)
(air whooshing)