Citrix XenServer 5.6 Essentials editions
Virtualization for every server in the enterprise.

XenServer Std and Enterprise NOW offered FREE

Citrix XenServer™ is available in four editions, providing flexibility based on infrastructure provisioning requirements, application functionality and system scalability.

Platinum Edition
For large, complex server environments and server farms, the Platinum Edition not only virtualizes server workloads but also provides dynamic workload management by extending the power of the dynamic workload streaming to both physical and virtual servers. Includes a Provisioning Server.
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Enterprise Edition
For server environments with demanding uptime requirements, the Enterprise Edition provides flexible, aggregated pools of computing and shared storage resources with live migration and high availability.
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Standard Edition
For a multi-server environment with demanding workloads, the Standard Edition is a feature-rich server virtualization solution with multi-server management and enterprise scalability for business-critical workloads
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Express Edition
For single server deployments and static workloads, the Express Edition is a free starter edition that brings virtualization to every server in the enterprise.
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Standard Edition:
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All editions are fully compatible. As the requirements of the business scale up and additional capabilities are required such as additional capacity, pooled resources, shared storage and XenMotion live migration, Citrix XenServer systems can be upgraded in place via license key, with no additional software installation or downtime required. XenServer pricing is done on a per server basis.

Using XenServer for BCP and DRP

Citrix XenServer is the only enterprise-class, cloud-proven virtualization platform that delivers all of the critical features needed for any server and datacenter virtualization implementation—scalability for any size business, support for Windows® and Linux OSs and complex storage needs, centralized multi-server management, live virtual machine migration, and much more. No matter where you choose to begin with XenServer, all editions are compatible and can be upgraded in place via license key, with no additional software installation or downtime required. Purchasing XenServer is simple with pricing appointed on a per server basis
XenServer Version 5.6 Features		Free Edition	Advanced Edition	Enterprise Edition	Platinum Edition
Free	XenServer hypervisor
virtual infrastructure	IntelliCache
	Resilient distributed management architecture
	VM disk snapshot and revert
	Resilient distributed management architecture
	XenCenter management
	Conversion tools
	XenMotion® live Migration
Advanced	Distributed virtual switching
management and	Heterogeneous pools
automation	High availability
	Memory optimization
	Performance alerting & reporting
	Dynamic workload balancing
	Host power management
	Live memory snapshot and revert
	Provisioning services (virtual)
	Role-based administration
	StorageLink
	Web self-service with delegated admin
	Automated VM protection and recovery
	Lab manager with self-service portal
	Provisioning services (physical)
	Site recovery

It is such a fast changing world in IT that new versions and “point” releases are being released all within month of previous versions.

The beta is scheduled to last four weeks (standard disclaimer applies: actual release will be determined by test results) so Citrix are asking that you get feedback in as early as possible.
XenServer 5.5 contains several new features:

• Active Directory integration. Specify the AD domain to use for authentication by the pool and use your AD credentials to connect to the pool via XenCenter and ssh. You control which AD users/groups are allowed access.
  
  
• Workload balancing. Guest and host performance metrics are used to create star ratings for individual VM placement and balancing recommendations for resource pools to achieve optimal performance.
  
  
• LVHD. Fast cloning and snapshots are now supported on all SR types through integration of our software VHD stack and LVM-based Storage Repositories (SRs)
  
  
• Snapshot support in XenCenter. Create and manage disk snapshots from within XenCenter.
  
  
• StorageLink integration. CLI-only support for a new StorageLink Gateway SR that adds native standards-based support for HP MSA, HP EVA, EMC Clariion, and NetApp storage arrays over iSCSI and Fibre Channel with optional automated initiator/fabric/array management
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• Expanded guest OS support. RHEL 5.3, Debian Lenny, and SLES 11 Linux guests.

XenServer 5.5 support for SUSE Linux Enterprise Server

XenServer 5.5 is support for SUSE Linux Enterprise Server (SLES) 11, Debian 5.0 and RedHat/CentOS/Oracle 5.3 running as guests. Also, the new XenConvert supports virtual-to-virtual migration from VMware's Virtual Machine Disk Format to the Virtual Hard Disk (VHD) format used by Citrix and Microsoft, plus support for the Open Virtualization Format, Open Virtual Appliance and XenServer Virtual Appliance formats.

XenServer storage integration

Citrix also announced version 5.5 of its add-on management pack Essentials for XenServer and Hyper-V. Highlights of the release are the previously announced automated lab management and dynamic workload balancing, and improved integration with third-party storage.

Citrix's StorageLink technology offers storage integration

Third-party storage integration, which could drive wider adoption of XenServer, occurs via Citrix's StorageLink technology, a set of application programming interfaces that allows XenServer to take advantage of native features of the underlying storage array. Such features include snapshotting, deduplication and thin provisioning. With this release, the number of partners that have integrated or committed to StorageLink increases to 20.

New disk array manufacturers writing to StorageLink include Compellent, Hewlett-Packard Co., LSI Corp., Pillar Data Systems, Reldata Inc. and Xiotech Corp., in addition to existing partners NetApp and Dell EqualLogic. Citrix has also lured SAN networking equipment makers (QLogic Corp., Brocade Communications Systems, Emulex Corp.), and storage software providers (CA, CommVault, DataCore Software Corp., FalconStor Software, PHD Virtual Technologies, SteelEye Technology and Vizioncore Ltd.) into the StorageLink fold. One notable absence on the list is EMC Corp., VMware's parent company.

XenServer Consolidated Backup feature

Broader storage array support is a good thing, but StorageLink's real coup will be to improve XenServer's backup story, said Chris Wolf, an analyst at the Burton Group. Most backup software providers already support VMware; next on their list is Microsoft Hyper-V, and "Citrix after that," Wolf said. But because Essentials works with both XenServer and Hyper-V, "this allows Citrix to ride on Microsoft's coattails and get supported a lot faster."

Speaking of backup, XenServer 5.5 also touts a new Consolidated Backup feature, which allows third-party software providers to interface directly with XenServer and provide full and incremental, in-guest, file- and image-level backups of virtual machines, the company reported. It also allows administrators to schedule backups and snapshots directly from XenCenter, XenServer's management console. At the same time, New Age Technologies' Snowden cited XenServer 5.5's new support for the Logical Volume Manager, which he said will make it easier for administrators to work with VHD files, regardless of whether they use NAS or SAN-based storage.