Last updated on July 12, 2022
XenApp vs XenServer: What’s the Difference?
Which will win in a XenApp vs XenServer showdown? Neither, as these two perform different functions. Citrix XenApp (now known as Citrix Virtual Apps) is an application virtualization platform, but Citrix XenServer (now known as Citrix Hypervisor) is a type-1, native, or bare-metal hypervisor. Thus, XenApp virtualizes applications for remote access from anywhere using any type of device. On the other hand, XenServer runs directly on host machines and manages both applications and desktops within an organization’s virtualized environment. This article discusses these technologies in more detail.
What Is Citrix XenApp?
Citrix XenApp is the virtual applications component in the Citrix Apps and Desktops product suite. XenApp performs application delivery functions, with applications running directly from XenApp Servers hosted on the cloud, on-premises and in hybrid datacenters, and sent over the network using the proprietary Citrix HDX protocol to client devices running all kinds of OSs.
In a Citrix XenApp environment, it may appear to users that their devices are running the virtual applications locally. However, what’s really happening is that the applications are being served over the network, with the server performing all the required processing. When application screens appear on endpoint devices, users enter keystrokes and mouse clicks, which are then captured and sent over the network back to the host server. The screens on the endpoint devices are then refreshed and updated with the information entered by the users. This process is repeated until users log off of the applications.
Since virtual applications reside on the XenApp Server, the type of device used to access the applications is not important, although Citrix Receiver is required to be installed on the device. Still, even older devices that would ordinarily not meet an application’s system requirements can be used to access virtual applications. Multiple users can also access the same virtual applications simultaneously.
What Is Citrix XenServer?
Citrix XenApp vs XenServer – the main difference is that XenServer is based on the open-source Xen Project hypervisor. Now known as Citrix Hypervisor, XenServer is a type-1 or bare-metal hypervisor, which means that it runs directly on the physical hardware itself, rather than as a software layer on top of the OS. Typical hypervisors of this type are often more powerful and efficient than type-2 hypervisors, which run on top of the operating system like any other computer program. It supports the major server operating systems, including Windows Server and Linux.
As a bare-metal hypervisor, Citrix XenServer manages hardware resources like memory, processor, networking and storage to the VMs. It also acts as the underlying hardware for multiple guest operating systems and applications, or virtual machines (VMs), on the multiple host machines in your virtual desktop infrastructure (VDI). It eases VM management by allowing the creation of templates from snapshots and live migration of VMs between hosts.
XenServer allows the delivery of processing-intensive graphics and provides robust security features. It is also used as the centralized management tool for desktop virtualization, server virtualization, cloud optimization, and provisioning in a Citrix-powered virtualized environment.
Citrix Hypervisor is offered in the entry-level Standard and the Premium Enterprise editions. The Premium Edition offers more advanced features such as automated Windows VM driver updates, SMB storage support, dynamic workload balancing, VMware vSphere to XenServer conversion, in-memory read caching and live patching.
XenApp vs XenServer: How are they Related to Each Other?
XenApp runs on the proprietary, service-oriented FlexCast Management Architecture (FMA), which allows interoperability among various Citrix products, including XenServer.
A typical XenApp deployment, or Site, often includes the following components:
- Delivery Controller, which is responsible for central Site management. For deployments with virtual machines hosted on a hypervisor or cloud service, communications between Delivery Controllers and the hypervisor are facilitated through a host connection. Sites may have more than one Delivery Controller, depending on your organization’s requirements.
- A Microsoft SQL Server database for storing configuration and session information.
- Virtual Delivery Agents (VDAs) that are installed on VMs hosting your applications. These allow VMs to be registered with the Controller and user access to the applications installed on the VMs.
- Citrix Storefront, which is responsible for delivering the applications to your users, allowing a consistent user experience across devices.
- Citrix Receiver client software, which is installed on user devices for easy, self-service access to your applications.
- Citrix Studio, which is the management console for your applications and is used to allocate and track your Citrix XenApp licenses.
- Citrix Director for troubleshooting any issues that may arise from your XenApp Server deployment.
- Citrix License Server to help manage your Citrix XenApp licenses. Each Site must have at least one License Server.
- Hypervisor or Cloud service, which is the host for your Site’s VMs. XenApp supports an array of hypervisors and cloud services.
Optional components include Provisioning Services, NetScaler Gateway and NetScaler SD-WAN.
XenServer is provided free of charge to Citrix Virtual Apps and Desktops customers. If your organization uses XenApp for application delivery, you can utilize XenServer as a hypervisor to broker operations, load balance connections, and optimize your Citrix virtualization environment.
What Are Alternatives to XenServer?
Aside from XenServer, other type-1 hypervisors on the market include Microsoft Hyper-V, VMware vSphere, and Red Hat Kernel-based Virtual Machine (KVM).
Microsoft Hyper-V’s notable features include persistent memory support and Resilient File System (ReFS) deduplication. ReFS is a new Microsoft file system designed for maximum data availability and data integrity.
VMware vSphere provides several components that help abstract memory and other resources into multiple VMs. It is designed for high availability and fault tolerance.
Essentially, Red Hat KVM transforms any Linux-based system into a type-1 hypervisor. It is designed for scalability, live and storage migration, and container and disaster recovery support. Red Hat KVM is the successor to Red Hat’s own implementation of the open-source XenServer hypervisor.
Aside from its native support for XenServer, XenApp also supports Microsoft Hyper-V (via the System Center Virtual Machine Manager), VMware vSphere and Nutanix Acropolis. It does not offer support for Red Hat KVM.
XenApp vs XenServer: An Alternative with Parallels RAS Hypervisor Flexibility
Parallels® Remote Application Server (RAS) is an all-in-one application delivery platform that reduces your hardware footprint and VDI setup costs. It requires minimal knowledge to configure and manage, enabling organizations to reduce IT complexity while increasing productivity. Full training on Parallels RAS is provided free of charge.
Parallels RAS supports the major hypervisors, including Microsoft Hyper-V and VMware ESXi, and hyper-converged infrastructures such as Nutanix Acropolis and Scale Computing HC3. It helps organizations build a multi-cloud-ready and flexible IT infrastructure that can be hosted either on-premises or on the public cloud, or a mix of both.
To check how Parallels RAS can help streamline your organization’s application delivery, download the trial!
