Add Azure Autoscale settings

Efficient hosting of applications in a cloud involves easy and cost-effective management of resources depending on the application demand. To meet increasing demand, you have to scale network resources upward. Whether demand subsides, you must scale down to avoid the unnecessary cost of idle resources. To minimize the cost of running the application, you have to constantly monitor traffic, memory and CPU use, and so on. However, monitoring traffic manually is cumbersome. For the application environment to scale up or down dynamically, you must automate the processes of monitoring traffic and of scaling resources up and down whenever necessary.

You can use Autoscale with Azure virtual machine scale sets (VMSS) for VPX multi-IP standalone and high availability deployment on Azure.

Integrated with the Azure virtual machine scale sets (VMSS) and Autoscale feature, the Citrix ADC VPX instance provides the following advantages:

  • Load balance and management: Auto configures servers to scale up and scale down, depending on demand. The VPX instance auto detects the VMSS Autoscale setting in the back-end subnet in the same resource group as the VPX instance and allows the user to select the VMSS Autoscale setting to balance the load. All of this is done by auto configuring Citrix ADC virtual and subnet IP addresses on the VPX instance.
  • High availability: Detects Autoscale groups in the same resource group and load-balance servers.
  • Better network availability: The VPX instance supports back-end servers on different virtual networks (VNets).

VPX Azure Autoscale

For more information, see the following Azure topic

Before you begin

  1. Read Azure-related usage guidelines. For more information, see Deploy a Citrix ADC VPX instance on Microsoft Azure.

  2. Create one or more Citrix ADC VPX instances with three network interfaces on Azure according to your requirement (standalone or high availability deployment).

  3. Open the TCP 9001 port on the network security group of the 0/1 interface of the VPX instance. The VPX instance uses this port to receive the scale-out and scale-in notification.

  4. Create an Azure virtual machine scale set (VMSS) in the same resource group. If you don’t have an existing VMSS configuration, complete the following tasks:

    a) Create a VMSS

    b) Enable Autoscale on VMSS

    c) Create scale-in and scale-out policy in VMSS Autoscale setting

    For more information, see Overview of Autoscale with Azure virtual machine scale sets.

  5. Create an Azure Active Directory (ADD) application and service principal that can access resources. Assign contributor role to the newly created AAD application. For more information, see Use portal to create an Azure Active Directory application and service principal that can access resources.

Add VMSS to a Citrix ADC VPX instance

You can add the Autoscale setting to a VPX instance with a single click by using the GUI. Complete these steps to add the Autoscale setting to the VPX instance:

  1. Log on to the VPX instance.

  2. When you log on to the Citrix ADC VPX instance for the first time, you see the Set Credentials page. Add the required Azure credentials for the Autoscale feature to work.

    Autoscale credentials

    The Set Credential page appears only when the application ID and API access key are not set or the correct application ID and API access keys (same as application secret) is not set in the Azure portal.

    When you deploy the “NetScaler 12.1 HA with back end Autoscale” offer from the Azure Marketplace, the Azure portal prompts for Azure service principal credentials (application ID and API access key).

    Azure Autoscale offer

    Azure principal credentials

    For information about how to create an application ID see Adding an application and to create an access key or application secret see Configure a client application to access web APIs.

  3. In the default cloud profile page, enter the details, as shown in the following example, and click Create.

Azure Autoscale cloud profile

Points to keep in mind while creating a cloud profile

  • The virtual server IP address is auto-populated from the free IP address available to the VPX instance. For more information, see Assign multiple IP addresses to virtual machines using the Azure portal.
  • Autoscale setting is prepopulated from the VMSS Autoscale setting configured in the current resource group on your Azure account. For more information, see Overview of Autoscale with Azure virtual machine scale sets.
  • While selecting the Auto Scaling Group protocol and port, ensure your servers listen on those protocol and ports and you bind the correct monitor in the service group. By default, the TCP monitor is used.
  • For SSL Protocol type Autos Scaling, after you create the Cloud Profile the load balance virtual server or service group will be down because of a missing certificate. You can bind the certificate to the virtual server or service group manually.

After the first time logon, if you want to create a cloud profile, on the GUI go to System > Azure > Cloud Profile and click Add.

Add Azure cloud profile

The Create Cloud Profile configuration page appears.

Create Azure cloud profile

Cloud Profile creates a Citrix ADC load-balancing (LB) virtual server (virtual server) and a service group with members (servers) as the servers of the Auto Scaling Group. Your back-end servers must be reachable through the SNIP configured on the VPX instance.

To view autoscale-related information in the Azure portal, go to All service > Virtual machine scale set > Select Virtual machine scale set > Scaling.

Add Azure Autoscale settings