Free Fault Tolerant Load Balancing using Citrix NetScaler Express (Part 1)

In this article we will describe the set-up and configuration of the NetScaler VPX including High Availability/Fault Tolerance.

If you would like to read the other parts of this article series please go to:

Citrix offers a NetScaler VPX Express edition. This is a full functioning freeware virtual appliance with advanced Load Balancing features. The NetScaler VPX Express is not the only freeware load balance appliance, but unlike most competitors the NetScaler VPX Express edition supports a High Available/Fault Tolerant configuration. 

The VPX Express is limited to 10Mbit throughput, but this is more than enough for lots of load balancing set-ups. Good examples are the Citrix StoreFront/Web Interface component, the Citrix DDC functionality, Microsoft RD Web Access and MS RD Connection Broker. In this article I will describe the set-up and configuration of the NetScaler VPX including High Availability/Fault Tolerance. In upcoming articles we are going to use this configuration of load balance services based on this set-up. 

Importing the NetScaler VPX Express

First step is downloading the NetScaler VPX Express appliance. The download can be found on the Citrix website. To access this page you need to have a MyCitrix account, which can be created without any costs. The virtual appliance is available for XenServer, KVM, Hyper-V and ESX. Pick the download for your virtualization platform.

                                          Figure 1: Download NetScaler VPX

After downloading the virtual appliance it’s time to import the appliance into your virtual infrastructure. The import is pretty easy for most of the hypervisors and Citrix describes the steps in their e-Docs:
I will use Hyper-V, but I’m running on a higher version of Hyper-V (2012R2) where the procedure via Import Virtual Machine does not work. With the latest releases of NetScaler VPX, the platform is officially supported, but there is a different way to add the NetScaler VPX appliance on the hypervisor platform.

To add the NetScaler Appliance to your Hyper-V 2012R2 (or Windows 8.1) infrastructure first create the directory where you would like to store the VM data into and copy the dynamic.vhd file out of the NetScaler VPX Express and download into this directory.

      Figure 2: Copy the dynamic.vhd into the directory

Next we start the creation of a new Virtual Machine. In my case I’m using the Hyper-V Manager and start the New Virtual Machine Wizard. I will label my NetScaler VMs NS01 and NS02 and will enter the store location to the just created directory (which stores the NetScaler VHD file).

      Figure 3: Specify Name and Location within the Virtual Machine Wizard

In the wizard select the Generation 1 type VM, at least 2048 MB memory, configure the correct VLAN into your infrastructure, followed by selecting Use an existing virtual hard disk and specify the just copied VHD file.

      Figure 4: Use an existing virtual hard disk

After the creation, open the Virtual Machine Settings and change the number of virtual processors to 2.

     Figure 5: Change the number of virtual processors

When the NetScaler VPX import is completed it’s time to start up the VM. For the first part you need to have a connection to the VM itself. When started you need to enter the basic network information. You need to provide an IPv4 address, a subnet mask and the default gateway. This IP address is being used as the IP address to manage/configure the NetScaler. In NetScaler terms this is the NetScaler IP Address (NSIP). 

After entering the information you need to save the entered information. The NetScaler will reboot and after that we can manage the NetScaler via an Internet browser. Again to set-up a high available/fault tolerant NetScaler infrastructure you need to execute this step on both NetScaler, where both require a unique NetScaler IP address logically. In my environment I’m using and

     Figure 6: Providing the basic network information

Open an Internet Browser and enter the configured IP address. The logon page is shown. The default logon is username nsroot with the same password (nsroot).

               Figure 7: NetScaler logon page

The intial configuration wizard of the NetScaler will automatically be started.

      Figure 8: initial configuration of your NetScale

The wizard starts with the second step where you need to provide the Subnet IP address (SNIP). This IP address is being used for communicating with the back-end infrastructure components that are configured as connections within the virtual servers. I’m using and for this article.

      Figure 9: Configure Subnet IP Address

The third step is to configure the hostname, a DNS server and the timezone.

                                            Figure 10: Configure Host Name, DNS and Time Zone

After this step the NetScaler needs to be rebooted.

                                          Figure 11: Reboot NetScaler

Although the NetScaler VPX Express is free, a license needs to be added. The free license file can be grabbed from the same page as the NetScaler VPX download. For the license part you need to have the hostID of the NetScaler VPX. This is actually the MAC address of the NIC. You find this within the hypervisor management console or skip the initial configuration wizard (choose license and specify Do it later) and find the host ID within Configuration – System within Hardware Information.

              Figure 12: Determine the Host Id

When you choose configuration again the initial wizard is shown again to add the license file. The first step is to get the license file. This is accomplished via the same URL as you download the appliance and browse to the end of the page, where you find the License part and choose Get License.

      Figure 13: Determine the Host Id

First you need to accept the license agreement as shown in  Figure 14.

     Figure 14: Accept the license agreement.

When you haven't downloaded a license you will have a button Get License, the next time the button is called Retrieve More licenses. Whichever option you have the button will generate a new serial number (see Date Issued). Choose the Serial Number for the next step.

                 Figure 15: Retrieve more licenses, followed by selecting the generated serial number.

A warning appears that you need to have the license server host name or host ID. As described earlier we need the host ID for the NetScaler Express.

     Figure 16: License Server Name or Host ID required.

When we continue we can enter the hostID, all other parts are default. In the following screen we need to confirm that we entered the correct information.

      Figure 17: Entering and confirming the hostID.

A message appears that the allocation was successful and a question if you want to download the license file.

                                     Figure 18: Allocation completed, downloading the license file.

At this time we successfully acquired and downloaded a license file for the NetScaler VPX Express, which we can add to the NetScaler Express configuration. You need to acquire a license file for both NetScaler Express appliances.

     Figure 19: License file downloaded.

Now we have a license we can continue with step 4 of the initial configuration. By choosing the configuration tab we will continue with this wizard.

     Figure 20: License file downloaded.

Choose the option “Upload license from a local computer”, followed by Browse. Browse to the location where you just downloaded the license file.

      Figure 21: Licenses in the initial wizard.

When the file is added into the appliance an Updated Successfully message will appear. To use the added license the appliance needs to be rebooted.

     Figure 22: License uploaded

When the appliance is started again and you logon to the management console, the license information is shown. This information acknowledges that the license uploading is actually successfully and the NetScaler VPX Express is ready to use.

     Figure 23: License successfully configured

When on both appliances the license file is uploaded and applied it’s time to configure the appliance in a high available/fault tolerance set-up. This is accomplished via the Configuration tab, within System – High Availability. Within this component an Add button is available to add a node for high availability.

     Figure 24: High Availability

In the next window the IP address of the other NetScaler VPX Express needs to be entered including the username and password of that NetScaler.

                   Figure 25: Add node to HA

The node is added and one of the NetScaler VPX Express appliances will become the Primary node and the other one the secondary.

      Figure 26: High Availability configured

Don’t forget to save the configuration otherwise after a reboot the set-up is not available anymore. Use the disk icon on the right side of the management console and choose Yes to confirm to save the running configuration.

                                      Figure 27: Saving current configuration


In this first part I described the installation and configuration of the NetScaler VPX Express on Hyper-V 2012R2. We downloaded the appliance, added to the hypervisor and configured it on the network. In the next step we set-up a high available configuration based on two NetScaler VPX Express appliances.

In upcoming articles we are going to use the NetScaler VPX Express set-up to load balance different services like Citrix StoreFront, Citrix XML Broker, Microsoft RD Web Access and Microsoft RD Connection Broker.

PS. Don’t forget to change this default password of the nsroot account via System – User Administration – Users.


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