Citrix Systems offers a comprehensive family of virtualization products used by more than 100 million people worldwide. XenServer is an enterprise-class virtual infrastructure solution that offers server and workload management, live migration, disaster recovery, low maintenance, fast setup (what Citrix calls "10 to Xen"), and high performance for Windows and Linux applications. Like VMwareís vSphere virtualization platform, an entry-level version is available as a free download. The free version of XenServer is quite powerful, with no limit to servers, virtual machines, or memory, and includes advanced features such as live migration support and centralized multi-server management.
More powerful versions of XenServer and complementary products such as XenApp and Citrix Essentials for Hyper-V can be licensed to provide enterprise-class capabilities in key areas that include application delivery, availability, load balancing, fault-tolerant redundancy, realtime monitoring, administration, and provisioning. Progent's Citrix-certified consultants can help you understand the business benefits of XenServer and other Citrix products, and can help you plan, test, implement, troubleshoot, and support a XenServer deployment. Progent can also assess your existing XenServer environment and help you optimize consolidation, performance, security and compliance, availability, and recoverability.
Architecture of Citrix XenServer with the Xen Hypervisor
Citrix XenServer Hypervisor Architecture
XenServer is built around the Xen hypervisor, a performance-optimized "base-metal" design that communicates directly with its hardware host without requiring the intervention of a full-blown, high overhead operating system. This architecture is similar to VMware's vSphere hypervisor and contrasts with Microsoft's Hyper-V, which must be installed on top of a specialized version of Windows Server 2008. Unlike VMware's proprietary approach, the Xen hypervisor features an open architecture that has been field proven in more than a dozen commercial virtualization products. In fact, the Xen hypervisor drives the Amazon Elastic Cloud, the world's largest virtualization deployment. An example of the advantages of XenServer's open architecture approach is that customers can utilize the advanced capabilities built into their existing storage systems such as snapshotting, replication, and provisioning without configuring and managing unfamiliar, proprietary utilities.
XenServer introduced the concept of paravirtualization, which allows the guest operating system to participate actively in the virtualization process. Paravirtualization, which has also been adopted by Microsoft in Hyper-V, offers close-to-native performance and minimizes the size of the Xen hypervisor, allowing XenServer to support more virtual machines (VMs) on each physical server. Higher VM density lowers total cost of ownership by reducing equipment purchases, simplifying management and support, and reducing expenses for cooling, power, and data center space.
The Xen hypervisor has been paravirtualized for all major releases of Linux, including Red Hat Enterprise Linux, Novell SUSE, Debian, Oracle Enterprise Linux, and CentOS. Although Microsoft Windows cannot be completely paravirtualized, XenServer can take advantage of the hardware-assisted virtualization capabilities of the Intel VT and AMD-V processor families. Citrix offers additional support for Windows environments with Citrix Essentials for Hyper-V, which focuses on storage management and dynamic provisioning in Hyper-V environments, and with Citrix XenApp, the flagship Citrix platform for virtualizing and delivering Window applications.
Live Migration with XenMotion
A powerful feature included in the free version of XenServer is XenMotion, which makes it possible to move a virtual machine from one physical host to another without interrupting the virtualized applications that are running. Live migration, which can be accomplished with a simple drag and drop operation by an IT manager, eliminates downtime due to scheduled maintenance, patch installation, upgrades, security scans, memory tests, and other routine processes that can disrupt productivity even when everything is running smoothly.
By allowing you to relocate a virtual server seamlessly and effortlessly to different hardware, XenMotion eliminates the stress of racing the clock to perform maintenance and can contribute significantly to overall system availability and, consequently, worker productivity and customer satisfaction.
Features of XenCenter Management Console
The free version of XenServer includes Citrix XenCenter, a multi-server management console with a variety of powerful features that include:
- Physical-to-virtual & Virtual-to-virtual conversion
- Shared SAN and NAS storage
- XenMotion for hot migration of virtual machines
- Shared library of virtual machine templates
- Centralized management across multiple servers and configuration management
- Virtual infrastructure patch management
- Intelligent server maintenance mode
New features included with the free 5.5 release of XenServer include consolidated backup, enhanced conversion tools, enhanced search, and the ability to use Microsoft Active Directory credentials to mange XenServer hosts and log and audit user activity.
How Progent Can Help You with Citrix Virtualization Products
Progent's Citrix certified experts can help you evaluate, test, install, and support XenServer as well as other important virtualization products from Citrix by providing Citrix Essentials for Hyper-V consulting services, Citrix XenDesktop expertise, and Citrix XenApp support. Progent also offers configuration and troubleshooting assistance with Citrix Access Gateway, browser-based SSL VPN software that enables remote and mobile users to connect to a corporate network and gives administrators granular access control based on user identity and the configuration of the endpoint device. Progent also offers consulting support for System Center 2012 R2 Virtual Machine Manager (SCVMM 2012), Microsoft's solution for creating and managing private clouds that can combine Citrix XenServer and Microsoft Hyper-V hypervisors. To learn about Progent's consulting services for SCVMM 2012, visit SCVMM 2012 consulting services.
Progent's certified Cisco CCIE network engineers can help you optimize your network infrastructure to support Citrix products and Progent's business continuity consultants can show you how to leverage Citrix technology to build a high level of fault tolerance and to develop a practical disaster recovery plan that will protect your business network from prolonged downtime in case of a catastrophic failure. To ensure the security and compliance of your Citrix environment, Progent's CISM, GIAC, CISA, and CISSP-ISSAP certified security engineers can provide objective security vulnerability testing and remediation services.
To find out more about how Progent's Citrix consultants can help you deploy and support Citrix virtualization solutions, call Progent at 800-993-9400 or visit Contact Progent.