Multiple VMs and correlation to Cloud Services

Question

So I think I have a good handle on creating and managing VMs, Images, and Disks in Azure, but I am a little confused about the correlation between my CLOUD SERVICEs and the VMs I am running.

I have created and deleted a few VMs in the Preview Portal (and using PS) in the course of my testing, and originally thought that each VM would correspond to 1 CLOUD SERVICE.

But, depending on how I create the VM or Image I sometimes see a new service in the Cloud Services dashboard. These do not always match what I see in the old portal...

I also believe I can have multiple VMs running under the same Cloud Service, right?

WHAT IS THE RELATIONSHIP between a single VM and it's CLOUD SERVICE?

WHAT IS THE RELATIONSHIP between a single Image and it's CLOUD SERVICE?

Note: I had a Cloud Service disappear from my dashboard while I was writing this question... the service was created when I created my first VM thru the Portal... I have since deleted the VM but the service has always remained. (well until just now but I suspect it may reappear in the dashboard)

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Daniel Stoever

Answer 1

Hi Dan Z Stoever,

When you create an application and run it in Azure(as part of PaaS model), the code and configuration together are called a Windows Azure Cloud service.

From IaaS standpoint, When you create a VM, cloud service is automatically created for you and is associated with cloud service that was created automatically. You can choose to run a VM as standalone or share the workload with existing VM. If you choose to create a VM as standalone VM, then cloud service will serve as a medium to reach the VM from internet since DNS names are associated with cloud service. If you choose to share the workload of existing VM, then you select the previously created VM during the process of creation, so that multiple VMs can be clubbed under single cloud service name. Images are stored in Azure storage and may not have direct relation with cloud service.

Please let me know if this clarifies your question or need more explanation.

Thanks,

Hari

Answer 2

That makes sense, so the only follow up questions/clarifications I have are...

1) Since a cloud service is created automatically for a stand-alone VM, if I delete the VM it makes sense that I can safely (and should) delete the associated service, right?

2) For my 'disappearing/reappearing' Cloud Services that were automatically created for VM's which are now deleted, it sounds like a quirk in the dashboard that should fix itself after I delete the services...

What I have been working on is setting up a virtual network in a 'private cloud' with (3 VMs so far) - 

a domain controller with AD acting as a DNS server, a database server(SQL), and a SharePoint 2010 server. The purpose of the whole virtual network is to facilitate development of pilot projects for Azure and Office 365. I plan to add some more sharepoint servers and maybe this would be a good place to 'share the workload' under a common Cloud Service between multiple VMs ...thanks for your help Hari.

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Daniel Stoever

Answer 3

Hi Daniel,

You are right, you can safely delete the associated service for a standalone VM that was deleted. I'm haven't personally seen disappearing/reappearing cloud service issue. But i think , you should be fine after deleting the service. If it is not the case, please let us know and we will research and investigate further.

Thanks,

Hari