1 Introduction

Citrix Virtual Desktop Infrastructure is a virtualization server environment which allows remote access to users. With Citrix VDI, application traffic is delivered across a Wide Area Network (WAN).

Citrix VDI makes IT management much easier. Rather than maintaining PCs at local branch offices, Citrix VDI enables a corporation's IT department maintain virtual, location diverse PCs in a central location.

Users require confidence that the service is available when needed. Kemp LoadMasters help to provide reliability. When deployed as a pair, two LoadMasters give the security of High Availability (HA). HA allows two physical or virtual machines to become one logical device. Only one of these units is ever handling traffic at any particular moment. One unit is active and the other is a hot standby (passive). This provides redundancy and resiliency, meaning if one LoadMaster goes down for any reason, the hot standby can become active, therefore avoiding any downtime. For more information on HA please refer to the: High Availability (HA), Feature Description.

1.1 Document Purpose

This document provides guidance on deploying Citrix VDI with a Kemp LoadMaster. The Kemp Support Team is available to provide solutions for scenarios not explicitly defined.

The Kemp support site can be found at: https://support.kemptechnologies.com.

1.2 Intended Audience

This document is for anyone deploying Citrix VDI with a Kemp LoadMaster.

 

1.3 Architecture

2 Citrix VDI Template

Kemp has developed a template containing our recommended settings for the Citrix VDI Virtual Service. This template can be installed on the LoadMaster and used when creating the Virtual Service. Using a template automatically populates the settings in the Virtual Service. This is quicker and easier than manually configuring the Virtual Service. If needed, changes can be made to any of the Virtual Service settings after using the template.

Download released templates from the Templates section on the Kemp documentation page: http://kemptechnologies.com/documentation/.

For more information and steps on how to import and use templates, refer to the Virtual Services and Templates, Feature Description.

3 Configure the LoadMaster

The following sections provide step-by-step instructions on how to configure a LoadMaster to load balance the Citrix VDI workload.

3.1 Enable Subnet Originating Requests Globally

It is best practice to enable the Subnet Originating Requests option globally.

In a one-armed setup (where the Virtual Service and Real Servers are on the same network/subnet) Subnet Originating Requests is usually not needed. However, enabling Subnet Originating Requests should not affect the routing in a one-armed setup.

In a two-armed setup where the Virtual Service is on network/subnet A, for example, and the Real Servers are on network B, Subnet Originating Requests should be enabled on LoadMasters with firmware version 7.1-16 and above.

When Subnet Originating Requests is enabled, the LoadMaster routes traffic so that the Real Server sees traffic arriving from the LoadMaster interface that is in that network/subnet.

When Subnet Originating Requests is enabled globally, it is automatically enabled on all Virtual Services. If the Subnet Originating Requests option is disabled globally, you can choose whether to enable Subnet Originating Requests on a per-Virtual Service basis.

To enable Subnet Originating Requests globally, follow the steps below:

1. In the main menu of the LoadMaster Web User Interface (WUI), go to System Configuration > Miscellaneous Options > Network Options.

2. Select the Subnet Originating Requests check box.

3.2 Configure a Citrix VDI Virtual Service

The following are the steps involved and the recommended settings to configure a Citrix VDI StoreFront Virtual Service:

1. In the main menu of the LoadMaster Web User Interface (WUI), go to Virtual Services > Add New.

2. Enter a valid IP address in the Virtual Address text box.

3. Enter 443 in the Port text box.

4. Enter a recognizable Service Name, for example Citrix VDI StoreFront.

5. Ensure tcp is selected as the Protocol.

6. Click Add this Virtual Service.

7. Configure the settings as recommended in the following table:

Section	Option	Value	Comment
Standard Options	Force L4	Enabled
	Persistence Options Mode	None
	Scheduling Method	round robin
SSL Properties	SSL Acceleration	Enabled
	Reencrypt	Enabled
	Supported Protocols	TLS1.0; TLS1.1; TLS1.2; TLS1.3	While this workload may not support TLS1.3 yet, Kemp recommend enabling it for future proofing.
	Cipher Set	BestPractices
Real Servers	Real Server Check Method	HTTPS Protocol
	HTTP Method	HEAD
	Scheduling Method	least connection	ESP can be enabled if an ESP license is in place. For more information on ESP, refer to the ESP, Feature Description on the Kemp documentation page.

8. Add the Real Servers.

a) Expand the Real Servers section.

b) Click Add New.

c) Enter the IP address of the StoreFront server.

d) Enter 443 as the Port.

The Forwarding method and Weight values are set by default. An administrator can change these.

e) Click Add this Real Server. Click OK to the pop-up message.

f) Repeat the steps above to add more Real Servers as needed, based on the environment.

References

Unless otherwise specified, the following documents can be found at: http://kemptechnologies.com/documentation.

Virtual Services and Templates, Feature Description.

High Availability (HA), Feature Description

Last Updated Date

This document was last updated on 04 March 2022.