Virtualization and some coffee

Fresh from the factory, Update Rollup 6 has been released and shipped by Microsoft.

This isn’t a blog post that will point out all the bug fixes and the amazing work all of the teams has been doing, but rather point you towards a highly requested feature, that finally made its way to the tenant portal in Windows Azure Pack.

With Update Rollup 6, we now supports creation and restore of Hyper-V checkpoints on virtual machines, provided by the VM Cloud Resource Provider.

Tenants that have deployed virtual machines may now create checkpoints and restore them on their own, without any interaction from the cloud provider.

Let us have a closer look at how this actually works, how to configure it and what additional steps you might want to take as part of this implementation.

Enabling create, view and restore of virtual machine checkpoints at the Hosting Plan level

Once the UR6 is installed for WAP and the underlying resource provider, you will notice some changes in the admin portal.

First, navigate to a Hosting Plan of yours – that contains the VM Cloud Resource Provider.

When you scroll down, you can see that we have some settings related to checkpoints.

Create, view and restore virtual machine checkpoints – will let the tenants that has subscriptions based on this hosting plan, be able to perform these actions on their virtual machines.

View and restore virtual machine checkpoints – let the tenants view and restore virtual machine checkpoints, but not create them. This can for example be performed by the cloud provider on an agreed schedule.

When you enable either of these options, an update job is taking place at the plan level and communicates the changes back to VMM, ensuring that the tenants will have permissions to take these actions in the tenant portal once it has completed.

If we switch over to the tenant portal, we can see that when we drill into one of the existing VMs (click on the VMàDashboard) we have some new actions available.

If you would manage checkpoints for your VM Roles, you can of course do that too, but you then have to drill into each specific instance, as the VM role potentially can have multiple instances when supporting scale-out.

To create a new checkpoint, simply click on Checkpoint and type the name of the checkpoint and eventually a description.

If we switch back to the fabric and VMM, we can see that a VMM job has completed with details about the checkpoint process for this specific tenant, with the name and description we typed.

If we would like to perform the same operation again, creating an additional checkpoint on the same virtual machine, we get a message telling us that the existing checkpoint will be deleted.

This is because that the current checkpoint integration in WAP will only keep one checkpoint, and avoid the scenario where you could potentially have a long chain of differential disks.

When we create the second checkpoint, we can switch back to VMM to see what’s actually happening:

First, a new checkpoint is created.

Second, the previous checkpoint is deleted.

When we explore the checkpoints settings on the VM itself afterwards, we see that we only have the latest checkpoint listed.

Regarding the restore process, we can also perform this from the same view in the tenant portal.

Once you click on the restore button, the tenant portal will show you the metadata of the available checkpoint, such as name, description and when it was created. Once you click the confirm button, the restore process will start in VMM.

Now what?

If you are familiar with how checkpoints in Hyper-V works, then you know that each static disk will be either .vhd or .vhdx – depending on the format you are using (.vhdx was introduced with Windows Server 2012 and should be the preferred format, but Azure is still using .vhd).

Once you create a checkpoint, a new disk (.avhd or .avhdx) will be created– a differential disk, containing all the new write operations, while read operations will occur on both the parent disk (vhdx) and the newly created differential disk.

To summarize, this might not be an ideal situation when it comes to performance, life-cycle management and storage optimization.

Since we don’t have any action in the tenant portal to perform a delete operation, this can be scary in some scenarios.

The fact that the VM will always run on a checkpoint once a checkpoint is created, means you will always be able to restore to your latest checkpoint from the portal.

In order to solve this challenge, we can leverage the integration of Service Management Automation in Azure Pack.

One of the best things with Azure Pack and the VM Cloud resource provider, is that we can extend it and create valued added solutions and services by linking certain actions happening in the tenant portal, to automated tasks that are executed by a SMA runbook in the backend.

The following screenshot shows that there’s an event related to creation of VMM Checkpoints performed by the tenant, which can easily be linked to a runbook.

Here’s an example of a runbook that will check for checkpoints created on VMs belonging to a specific VMM Cloud that is used in a Hosting Plan in WAP. If there’s any checkpoints that exists, they will be deleted and the VMs will have their disks merged back to a static disk (.vhd/.vhdx).

<#

.SYNOPSIS

Wokflow to check for - and eventually delete old VM checkpoints

#>

workflow delete-scvmcheckpoint

{

# Connection to access VMM server.

$VmmConnection = Get-AutomationConnection -Name 'SCVMM'

$VmmServerName = $VmmConnection.ComputerName

inlinescript

{

# Import VMM module.

Import-Module virtualmachinemanager

# Connect to VMM server.

Get-SCVMMServer -ComputerName $Using:VmmServerName

$vms = Get-SCVirtualMachine | Where-Object {$_.Cloud -like "*Copenhagen IaaS*" -and $_.VMCheckpoints }

foreach ($vm in $vms)

{

Get-SCVMCheckpoint -VM $vm | Remove-SCVMCheckpoint -RunAsynchronously

}

}-PSComputerName $VmmServerName -PSCredential $VmmCredential

}

This simple code can so be added to a schedule that will execute this runbook on a daily basis – as an example, ensuring that no VMs in the cloud will run on a checkpoint on a long term.

Thanks for reading!

Posted by Kristian Nese at 11:34 AM No comments:

Hyper-V Hyper-V, PowerShell, SCVMM 2012 R2, Service Management API, SMA, WAP, WAPack

In order to get a good grasp on something new, like a technology, it is always important to find a use case.

Once you have a use case, I can ensure you that the learning process is much more interesting, fun – and perhaps easier too.

That is what I did when I went deep into Desired State Configuration. I found a use case.

My use case was to leverage DSC as part of VM Roles in Azure Pack in a way that would be valid for the future too.

Powershell has been around for some time now, and one of the best benefits by learning and using the shell is the amount of work you are able to do, combining modules, components, technologies and much more through the same API. Considering that everything that MS builds and do – regardless of cloud, will be accessible and manageable through Powershell in addition to other options, ensures that this is a real no-brainer.

With Windows Management Framework 4.0, we also got Powershell Desired State Configuration added to our table.

Powershell Desired State Configuration is Microsoft’s way to implement an idempotent configuration that ensures that the “desired state” will be reached by applying the entire configuration, regardless of the current state.

-But, what does this really mean? Aren’t we able to do everything using native Powershell scripts already?

That is correct. There’s no “limits” by using Powershell natively today.

However, with native Powershell scripts you are responsible for building all the error handling and logic into your scripts. And as you probably know, that can be both very time consuming and challenging.

Desired State Configuration handles this automatically for you, letting you make and deploy any incremental changes to your configuration over time without risking the system to be put in a bad state.

If you have any configuration drift? Depending on how the Local Configuration Manager is configured – the engine that’s responsible for applying the configuration and follow the instructions, the system can heal itself by enforcing the desired state.

Think of Powershell Desired State Configuration as a contract between you and your nodes (manageable objects).

In order to create and deliver this “contract”, Desired State Configuration is based on CIM – and use WinRM for communicating. CIM uses a language called Manaed Object Format – often referred to as “MOF”. Powershell Desired State Configuration is a way to create and distribute MOF files that can be applied to systems supporting this standard.

The way it’s applied to the node(s) is either through “Push” or “Pull”.

(The difference between Push and Pull is out of scope right now and deserves a dedicated blog post later on. I promise).

To put it short, the Pull mechanism requires some infrastructure in order to work, where the node(s) are talking to the Pull server – either through SMB, Http or Https.

The Push method is pretty straight forward and what you can start using right out of the box. DSC requires that WinRM listeners are configured so that the CIM can push the configuration to the remote systems.

configuration DNS

{

node kndsc006

{

WindowsFeature DNS

{

Name = "DNS"

Ensure = "Present"

IncludeAllSubFeature = $true

}

}

}

DNS

Start-DscConfiguration -wait -force -Verbose .\DNS

As you can see, the format here is quite easy to read.

We can easily see that we will install (Ensure = "Present") DNS (Name = "DNS") on the target node (kndsc006).

Actually, it is so easy to read that Powershell newbies like me are able to manage J

Hopefully this gave you some more context about the “why”, but we are not done yet.

In Azure today, we are able to leverage DSC as part of the VM extension, meaning we can create – upload – and apply our DSC configuration to Azure IaaS virtual machines. The method of applying the config for these VMs are “Push”.

As you probably know, we don’t have the exact same capabilities on-prem in order to leverage DSC as part of Azure Pack. However, we are able to simulate the same experience at some extent, by using the combination of DSC, SMA and VM Roles (http://kristiannese.blogspot.no/2015/03/application-modeling-with-vm-roles-dsc.html )

Moving forward, we know that the consistency across clouds will be as near as 1:1 with the introduction of Azure Resource Manager that will introduce us for a complete new way to interact with our cloud services – regardless of location. Also worth to note, the Azure Resource Manager itself will be idempotent.

What about your existing DSC scripts?

Exactly, that is the main point here. These configurations will be valid using Azure Resource Manager too J

So in essence, you invest in DSC now and use it both for Azure Pack (VM Roles + SMA) and Azure (VM Extension), and later on you can reuse the investment you’ve made into the era of Azure Resource Manager.

Hopefully this gave you some inspiration to start learning Desired State Configuration, available in Windows Management Framework 4.0 – but also available in 5.0 (which is in Preview).

Please note that everything you do in Azure when using the DSC VM Extension there is based on the 5.0 version.

Posted by Kristian Nese at 12:35 PM No comments:

Hyper-V ARM, Azure, Azure Resource Manager, Desired State Configuration, DSC, PowerShell, SMA, VM Roles

Earlier this year, I started to go deep into DSC to learn more about the concept, possibilities and most important, how we can improve what we already have and know, using this new approach of modeling.

For more information and as an introduction to this blog post, you can read my former blog post on the subject: http://kristiannese.blogspot.no/2015/03/dsc-with-azure-and-azure-pack.html

Desired State Configuration is very interesting indeed – and to fully embrace it you need to be comfortable with Powershell. Having that said, Desired State Configuration can give you some of what you are requiring today, but not everything.

Let me spend some minutes trying to explain what I am actually saying here.

If you want to use DSC as your primary engine, the standard solution to configure and deploy applications and services across clouds throughout the life cycle, there is nothing there to stop you from doing so.

However, given the fact that in many situations, you won’t be the individual who’s ordering the application, server and dependencies, it is important that we can make this available in a world full of tenants with a demand for self-servicing.

Looking back at how we used to do things before to handle the life-cycle management of applications and infra, I think it is fair to say it was something like this (in context of System Center):

1)We deployed a Virtual Machine based on a VM Template using SCVMM

We either

a)Manually installed and configured applications and services within the guest post VM deployment

b)Used SCCM to install agents, letting the admin interact with the OS to install and configure applications using a central management solution

2)If we wanted to provide monitoring, we then used SCOM to roll out the agents to our servers and configured them to report to their management group

3)Finally yet importantly, we also wanted to be secure and have a reliable set of data. That’s why we also added backup agents to our servers using SCDPM

In total, we are talking about 4 agents here (SCVMM, SCCM, SCOM and SCDPM).

That is a lot.

Also note that I didn’t specify any version of System Center, so this was probably even before we started to talk about Private Clouds (introduced with System Center 2012).

And that’s the next topic, all of this in the context of cloud computing.

If we take a walk down the memorial lane, we can see some of Microsoft’s least proud moments, all the attempts in order to bring the private cloud a fully functional self-service portal.

-We’ve had several self-service portals for VMM that later was replaced by different solutions, such as Cloud Service Process Pack and App Controller

-Cloud Service Process Pack – which was introduced with SC 2012 – where all the components were merged into a single license, giving you out-of-the-box functionality related to IaaS.

The solution was one of the worst we have seen, and the complexity to implement it was beyond what we have seen ever since.

-AppController was based on Silverlight and gave us the “single-pane of glass” vision for cloud management. With a connector to Azure subscriptions (IaaS) and to private and service provider clouds (using SPF), you could deploy and control your services and virtual machines using this console

Although it is common knowledge that AppController will be removed in vNext of System Center (https://technet.microsoft.com/en-us/library/dn806370.aspx?f=255&MSPPError=-2147217396 ), AppController introduced us to a very interesting thing: self-service of service templates.

The concept of service templates was introduced in System Center 2012 – Virtual Machine Manager, and if we go back to my list of actions we needed to perform, we could say that service templates at some point would replace the need of SCCM.

Service Templates was an extension to the VM template. It gave us the possibility to design, configure and deploy multi-tier applications – and deploy it to our private clouds.

However, I have to admit that back then; we did not see much adoption of service templates. Actually, we did not see some serious adoption before Microsoft started to push some pre-configured service templates on their own, and that happened last year – at the same time as their Gallery Items for Azure Pack was released.

To summarize, the service template concept (which was based on XML) gave the application owners and the fabric administrators a chance to interact to standardize and deploy complex applications into the private clouds, using AppController. In the same sentence there we found AppController (Silverlight) and XML.

If we quickly turn to our “final destination”, Microsoft Azure, we can see that those technologies aren’t the big bet in any circumstances.

VM Roles are replacing service templates in the private cloud through Windows Azure Pack.

A VM Role is based on JSON – and define a virtual machine resource that tenants can instantiate and scale according to their requirements.

We have in essence two JSON files. One for the resource definition (RESDEF) and one for the resource extension (RESEXT).

The resource definition describes the virtual machine hardware and instantiation restrictions, while the resource extension definition describes how a resource should be provisioned.

In order to support user input in a user friendly way, we also have a third JSON file – the view definition (VIEWDEF), which provides the Azure Pack details about how to let the user customize the creation of a VM Role.

These files are contained in a package, along with other files (custom resources, logo’s etc) that describe the entire VM Role.

You might ask yourself why I am introducing you to something you already know very well, or why I am starting to endorse JSON. The answer lays in the clouds.

If you have every played around with the Azure preview portal, you have access to the Azure Resource Manager.

ARM introduced an entirely new way of thinking about you resources. Instead of creating and managing individual resources, you are defining a resource model of your service – to create a resource group with different resources that are logically managed throughout the entire life cycle.

-And guess what?

The Azure Resource Manager Templates is based on JSON, which describes the resources and associated deployment parameters.

So to give you a short summary so far:

Service Templates was great when it came with SCVMM 2012. However, based on XML and AppController for self-service, it wasn’t flexible enough, nor designed for the cloud.

Because of a huge focus on consistency as part of the Cloud OS vision by Microsoft, Windows Azure Pack was brought on-premises and should help organizations to adopt the cloud at a faster cadence. We then got VM Roles that should be more aligned with the public cloud (Microsoft Azure), compared to service templates.

So we might (so far) end up with a conclusion that VM Roles is here to stay, and if you are focusing too much on service templates today, you need to reconsider that investment.

The good, the bad and the ugly

So far, the blog post has been describing something similar to a journey. Nevertheless, we have not reached the final destination yet.

I promised you a blog post about DSC, SMA and VM Roles, but so far, you have only heard about the VM Roles.

Before we proceed, we need to be completely honest about the VM Roles to understand the requirement of engineering here. To better understand what I am talking about, I am comparing a VM Role with a stand-alone VM based on a VM Template:

As you can see, the VM Role gives us very much more compared to a stand-alone VM from a VM template. A VM Role is our preferred choice when we want to deploy applications in a similar way as a service template, but only as single tiers. We can also service the VM Role and scale it on demand.

A VM on the other hand, lacks all these fancy features. We can purely base a stand-alone VM on a VM Template, giving us a pre-defined HW template in VMM with some limited settings at the OS level.

However, please note that the VM supports probably the most important things for any production scenarios: backup and DR.

That is correct. If you use backup and DR together with a VM Role, you will end up in a scenario where you have orphaned objects in Azure Pack. This will effectively break the relationship between the VM Role (CloudService in VMM) and its members. There is currently no way to recover from that scenario.

This got me thinking.

How can we leverage the best from both worlds? Using VM Role as the engine that drives and creates the complexity here, supplemented by SMA and Desired State Configuration to perform the in-guest operations into normal VM templates?

I ran through the scenario with a fellow MVP, Stanislav Zhelyazkov and he nodded and agreed. “-This seems to be the right thing to do moving forward, you have my blessing” he said.

The workflow

This is where it all makes sense. To combine the beauty of VM Roles, DSC and SMA to achieve the following scenario:

1)A tenant logs on to the tenant portal. The subscription includes the VM Cloud resource provider where the cloud administrator has added one or more VM Roles.

2)The VM Role Gallery shows these VM Roles and provides the tenant with instructions on how to model and deploy the application.

3)The tenant provides some input during the VM Role wizard and the VM Role deployment starts

4)In the background, a parent runbook (SMA) that is linked to the event in the portal kicks in, and based on the VM Role the tenant chose, it will invoke the correct child runbook.

5)The child runbook will deploy the (stand-alone) VMs necessary for the application specified in the VM Role, join them to the proper domain (if specified) and automatically add them to the tenant subscription.

6)Once the stand-alone VMs are started, the VM Role resource extension kicks in (which is the DSC configuration, using push) that based on the parameters and inputs from the tenant is able to deploy and model the application entirely.

7)Once the entire operation has completed, the child runbook will clean-up the VM Role and remove it from the subscription

In a nutshell, we have achieved the following with this example:

1)We have successfully been able to deploy and model our applications using the extension available in VM Roles, where we are using Desired State Configuration to handle everything within the guests (instead of normal powershell scripts).

2)We are combining the process in WAP with SMA Runbooks to handle everything outside of the VM Role and the VMs.

3)We are guaranteed a supported life-cycle management of our tenant workloads

Here you can see some screenshots from a VM Role that will deploy Windows Azure Pack on 6 stand-alone VMs, combining DSC and SMA.

In an upcoming blog post, we will start to have a look at the actual code being used, the challenges and workarounds.

I hope that this blog post showed you some interesting things about application modeling with VM Roles, SMA and DSC, and that the times are a-changing compared to what we used to do in this space.

Posted by Kristian Nese at 11:04 PM No comments:

Hyper-V ARM, Azure Resource Manager, DSC, SCVMM 2012 R2, SMA, VM Roles, WAP, WAPack