Overview

RightScale provides support for Azure Resource Manager (also called Azure v2 or ARM) APIs. This is the 2nd generation “cloud” offering from MS Azure, and is significantly different from their earlier implementation.

Resource Mappings

As RightScale abstracts many different cloud resources in our API and UI, we must map resource offerings from clouds into RightScale resources. The table below lists the resource mappings as they relate to ARM.
Note that unless indicated otherwise, all resources and functionality described below will be supported in the Dashboard, CM API 1.5, and Self­-Service CAT files.

Azure Resource RightScale Resource Comments
Platform Image Image With property visibility = public
Marketplace Image Image 1. With property visibility = public
2. Marketplace images must be “enabled” in Azure before using in RightScale.
3. Images are refreshed once every 24 hours from Azure
User Image Image 1. With property visibility = private
2. Unmanmaged images must be stored within the system container of a storage account. Example:
<StorageAccount>/system/Microsoft.Compute/Images/vhds/Win2012R2wRL10-osdisk.08877202-d144-4c8e-bd97-695c3b848b88.vhd
VMs Instances
VM Size Instance Type
Virtual Machine Instance / Server
Public IP Address IP Address 1. Only those with ‘static’ allocation are listed. Those with ‘dynamic’ allocation are not listed but can be used when launching by setting the ‘associate_public_ip_address’ flag
2. Public IP Addresses created in RightScale will be associated with the “default” Resource Group for the region
Network Interface Network Interface
Network Security Group Security Group Security Groups created in RightScale will be associated with the “default” Resource Group for the region.
Limitations
Network Security Group ­- Security Rules Security Group Rule Limitations
Virtual Network Network
Resource Group Deployment
Storage Account Placement Group Microsoft - About Disks and VHDs
Virtual Network ­- Subnet Subnet
Network Interfaces IP Address Bindings
Disks Volumes ARM Managed Disks and Storage Account based VHDs are discovered as Volumes in RightScale.
Microsoft - Overview of Managed Disks
Microsoft - About Disks and VHDs

Resource Descriptions

Azure Resource Groups

RightScale will create and manage Resource Groups in Azure in 3 specific cases:

  • Default Resource Groups
  • Deployment-related Resource Groups
  • Instance-related Resource Groups

In addition to creating Resource Groups in the above scenarios, RightScale will also attempt to cleanup Resource Groups created by RightScale in certain scenarios. Details for this behavior are below.

Default Resource Groups

RightScale will create a default Resource Group for each ARM region when needed. This default Resource Group will be named: rs-default-[region] (e.g. rs-default-eastus). The default Resource Group will contain the following types of resources if a deployment is not specified when creating them: Networks, Subnets, Security Groups, IP Addresses, and Placement Groups (Storage Accounts).

These default Resource Groups will not be auto-removed per the procedure listed below, however they can be deleted via the Azure Portal. If a default Resource Group is deleted in Azure, it will be recreated when a resource type that belongs in the default Resource Group is created from RightScale.

In Azure Resource Manager, Resource Groups are a construct meant to group together resources that have a similar lifecycle. The clear parallel in RightScale is the Deployment. For this reason, you can associate a Deployment in RightScale with a Resource Group in ARM. Once this association is established, tags will be synchronized between the two. Any instance/server/array launched in the Deployment will launch into the associated Resource Group. Likewise, any resource created natively in ARM in that Resource Group(after the association has been created) will show up in the associated RightScale Deployment.

RightScale creates a Resource Group in ARM when the first ARM server, Network, Subnet, Security Group, IP Address and placement group in the Deployment is launched/created, and this Resource Group is used for all servers/arrays/instances in that Deployment thereafter. The Resource Group in ARM will be named after the Deployment name in RightScale (sanitized to meet Azure naming rules).

Resource Groups that are created by RightScale to manage Deployments will have two Azure Billing Tags named RightScale Deployment and RightScale Deployment Href. These tags impact the management of Resource Groups by RightScale and should not be removed.

If an Instance (not Server) is launched through RightScale without an associated Deployment RightScale, a Resource Group is created specifically for that instance. The Resource Group in ARM will be named after the Instance name in RightScale (sanitized to meet Azure naming rules).

Resource Groups that are created by RightScale to manage an Instance will have two Azure Billing Tags named RightScale Deployment and RightScale Deployment Href. These tag impact the management of Resource Groups by RightScale and should not be removed.

Resource Groups and Resources

For any resource in RightScale that exists in a Deployment, including instances, servers, IP Addresses, PlacementGroups, SecurityGroups, and Networks, its Resource Group is automatically set by RightScale when it is launched, using the Resource Group associated with the Deployment (or a new Resource Group if one is not associated).

Note that some of these resources are not visible in the RightScale Deployment view, but they are associated with a deployment when being created and will have a Deployment link in the API. For any resource that is created without an associated Deployment, it is created in the Default Resource Group for the region.

Associating a Resource Group and a Deployment

If you would like a Deployment to be associated with a specific Resource Group, you can edit the Deployment and pick from any existing available Resource Group in ARM. If you pick 'None', then one will be created when needed (when a resource in the Deployment is created/launched).

When you associate an existing Resource Group with a Deployment, any new resources discovered in Azure from that point forward will automatically be placed in the associated Deployment and any existing resources will remain outside of that deployment.

You can change the associated Resource Group at any time. When you do so, the tags will start syncing to the new Resource Group, but any running resources in the Deployment in RightScale will not be modified - they will continue to exist in the Resource Group in which they were created.

As mentioned above, if a resource is created/launched in a Deployment that does not have a Resource Group associated with it, RightScale creates a new Resource Group in ARM with a similar name to the Deployment (sanitized per Azure naming conventions). In particular, this happens when a server/array/instance is launched or a Placement Group/Network/Security Group/IP Address is created and the Deployment does not have an associated Resource Group.

Cleanup of Resource Groups

For any Resource Group that is created by RightScale, the Resource Group will be deleted from Azure once the Deployment is deleted from RightScale.

Deleting Deployments

A Deployment in RightScale can be deleted once all of the associated cloud resources have been removed. For instances/servers/arrays, this means that there are no running instances in the cloud. For other resources, such as Networks/IP Addresses/Placement Groups/Security Groups, the resource must actually be deleted or disassociated from the Deployment before the Deployment can be deleted.

Managed Disks

Azure Managed Disks remove the requirement of managing Storage Accounts to contain your VM disks. You no longer have to create Storage Accounts and ensure you are are not exceeding their service limits. [Microsoft - Azure Managed Disks Overview]

RightScale discovers Azure Managed Disks as Volumes in RightScale -- the Resource UID will be the GUID of the disk, and it will list the Volume Type instead of the Placement Group. ARM Managed Disk Volume in CM

When creating a new Server, Instance or ServerArray in the Cloud Management UI, it will use Managed Disks by default. You are still able to use unmanaged disks if you prefer -- in this case you will be required to specify an existing or new Placement Group (Storage Account). ARM Managed Disk in CM

When creating a new Server, Instance or ServerArray via the API or Self-Service, the root_volume_type_uid attribute within the cloud_specific_attributes hash needs to be set to Standard_LRS or Premium_LRS based on the type of Managed Disk you want to provision.

cloud_specific_attributes do {
    "root_volume_type_uid" => "Standard_LRS" # Possible values: Standard_LRS, Premium_LRS
} end

To use Unmanaged Disks in a CAT resource, leave out the root_volume_type_uid attribute. A placement_group can optionally be specified, otherwise the default logic will be used.

placement_group "somestorageaccount" # Name of existing RightScale Placement Group (Microsoft Storage Account)

Full CAT Examples can be found in GitHub here:

For further information about Managed Disks, see the Azure Managed Disks Overview from Microsoft.

Storage Accounts

The following applies to ARM Storage Accounts when used through RightScale:

  1. Whenever an instance is launched without explicitly specifying the Storage Account, RightScale will use the Storage Account:
    • that has the fewest number of instances associated with it AND that is in the instance’s Resource Group
      OR
    • if there are no Storage Accounts with fewer than 20 instances, RightScale will generate a new Storage Account to use (see point 1 above). Auto-generated Storage Accounts will use the Standard_GRS Storage Account Type.
  2. Storage Accounts in Azure Resource Manager are called Placement Groups (type: storage) in RightScale. You will see them called Storage Accounts when in Azure­-specific views, and Placement Groups in the API and generic views in RightScale.

Storage Account Types

The following types of Storage Accounts can be created from the RightScale Cloud Management UI, via the API, or through Self-Service. When creating Placement Groups via the API or Self-Service, the account_type attribute within the cloud_specific_attributes hash would need to be set per the chart below:

Azure - Storage Account Type RightScale - account_type Value
Standard Locally-redundant storage (LRS) Standard_LRS
Standard Zone-redundant storage (ZRS) Standard_ZRS
Standard Geo-redundant storage (GRS) Standard_GRS
Standard Read-access geo-redundant storage (RA-GRS) Standard_RAGRS
Premium Locally-redundant storage (LRS) Premium_LRS

Virtual Networks

Since Azure Virtual Networks require​ at least one subnet, when you create an Azure Virtual Network in RightScale, a subnet will automatically be created for that network with the same network CIDR. This subnet can be modified immediately thereafter to customize it, as required.

Network Interfaces

When choosing multiple subnets, the security group selected will be applied to both subnets selected. There is a limitation that prevents you from choosing different security groups per subnet.

Instances

Azure Resource Manager VMs map to RightScale Instances, the same as all other supported Clouds.

Terminate Behavior

  • For VMs launched in a RightScale deployment, terminate action does: delete VM, Network interface and dynamically generated public ip (if there is one).
  • For VMs launched outside of a RightScale deployment, terminate action does: delete the resource group and all associated resources within it.
  • For VMs launched outside of a RightScale deployment but was RightLink-enabled, terminate action does: delete the resource group and all associated resources within it.
  • For VMs launched outside of a RightScale deployment but was later moved into a RightScale deployment, , terminate action does: delete the resource group and all associated resources within it.
  • For VMs launched via the Azure Portal, terminate action does: delete only the VM