Daniele Tosatto

XenServer 5.6 was announced a couple of weeks ago at Citrix Synergy, and this morning (Eastern US time) Citrix posted it for download on citrix.com.  If you are considering XenServer for the first time, or looking at upgrading to 5.6 from a prior version, here’s some information on what’s new that will help you:

Dynamic Memory Control.  Let’s say you have a few XenServer hosts.  You need to spin up some more VMs, but your VMs are configured to use all available resource pool memory.  However, you know that some of the existing VMs aren’t using all the physical memory you’ve allocated.  With XenServer 5.6, you can set memory ranges for VMs so that you can squeeze the physical memory used for existing VMs in order to let new ones on.  If you find that one or more VMs operating near the lower limit requires more memory, you can increase the minimum level on the fly without rebooting.

Role-Based Administration and Audit.  You’re the primary XenServer administrator.  You have a junior admin that you want to provide a lower level of access within XenCenter so that they can start/stop/reboot/snapshot VMs without either 1. bothering you to do it for them all the time, or 2. Giving them full access to the XenCenter console where they have access to networking and storage configurations.  If that junior admin deletes a VM, you’ll have an audit trail with a record of this change, and when it was performed.

Heterogeneous Pools. Let’s say you have a pool of 5 XenServer hosts, which run on year-old hardware with Intel Xeon 5400 processors.  Now you buy a couple of new servers, which have new Intel Xeon 5500 processors. With XenServer you can join them to the same pool and enable XenMotion, HA, Shared Storage, and Workload Balancing. In the past, you could “force join” the newer servers to the existing pool, but you’d have to be careful not to XenMotion between different processor types.  This feature works with Intel processors with “Flex Migrate” capability and AMD processors with “Extended Migration” features.  Note that live migration between Intel and AMD does not work. Citrix’ve added a new section on the HCL with the tested configurations.  Those that aren’t listed can be added by running through the Citrix Ready XenServer hardware test kit.

Memory Snapshots and one-click revert.  In addition to disk snapshots for backup, now you can snapshot the live running state of a VM.  In previous versions of XenServer, reverting to your snapshot was a multi-step process that was not ideal.  Now you just click “revert” in the snapshot manager.

Dynamic Workload Balancing with Power Management.  If you have a XenApp farm running 24×7,there is quite a bit of power wasted by those servers during nights and  weekends when only a handful of users are accessing applications.  Workload balancing can be scheduled to consolidate all of your idle XenApp servers on as few hosts as possible while powering off the newly vacated XenServer hosts. In the morning or after a weekend, those machines will power on and the VMs will be redistributed to handle the load.  Additionally, Workload Balancing includes a fully-automated mode with some new configuration options.  Example: if you have some VMs that you don’t want moving around, simply start those VMs on a specific host and exclude that host from WLB computations.

Increased scalability.  We’ve doubled support limits for logical processors and memory to 64 and 256 GB, respectively.  Up to 16 NICs per host are supported as well.

Updated Support for Provisioning Services (PVS).   PVS 5.6 has been updated, and includes a helpful new vDisk imaging wizard.   XenCenter is now more aware of PVS boot scenarios, namely through “boot from network” options in the new VM setup wizard.  One thing we’d like people to try (call it a “Tech Preview”) is streaming of XenServer bits themselves, in addition to VMs.  The eventual goal here is to greatly simplify management of XenServer updates and upgrades, just as PVS has done for XenApp and XenDesktop VMs.

Enhanced XenCenter. Did you run the XenDesktop setup wizard incorrectly and create a bunch of VMs that you now need to delete?  Use the multi-select feature, right-click, and select “delete.”  Need to start or shutdown a bunch of VMs at the same time?  Another good use for the multi-select option.  Other useful additions include one-step “VM move” (powered down) from array to array. Try right mouse clicking on a custom template and select “Instant VM from template.” You won’t be prompted to accept all the defaults, which you probably click right through anyway.

Enhanced support for iSCSI arrays with multi-IQN / IP configuration.  DataCore SANMelody is an example of an iSCSI array that advertises multiple IQNs with multiple IP addresses.  With 5.6, we aim to make the setup of XenServer with SANMelody arrays much easier with the wildcard IQN scan option.

OEM edition simplification.  We used to assist with the creation of HP and Dell-specific versions of XenServer, which they shipped onboard their servers.  This had some issues.  One key example: though “Update” releases were made available for OEM editions, individual hotfixes were not.  No more.  Now we have one set of bits and HP and Dell apply hardware specific “supplementary packs” which contain their management agents and other hardware-specific components.  You can also support BIOS locking if you have an OEM version of Windows that you want to run as a virtual machine on your XenServer host.

Advanced Edition.  HA, Dynamic Memory Control, Alerting, and Performance History for $1,000 per server. Note: for a full list of the features in each edition (including Free) see here:

Server-based pricing. This isn’t “new” per se, however it’s starting to matter a lot more when you compare costs of XenServer and vSphere on some of the latest servers.  Dell R815 and HP DL385 G7 servers now ship with 12-core Opteron 6000 processors.   The problem for VMware customers is that they won’t allow you to run vSphere Standard or Enterprise Edition on those servers.  In other words, VMware hates Moore’s Law.  With XenServer, we don’t care how many cores or sockets the server has; you pay the same price with any configuration.  Citrix loves Moore’s Law.

Initial SR-IOV platform support for NetScaler VPX. If you’ve got a server with an Intel SR-IOV capable NIC, you will soon be able to achieve near line-speed network performance to a XenServer virtual machine.  Initial tests within Citrix have shown ~ 108 Gbps of aggregate bandwidth to a NetScaler VPX virtual machine.  Note that the real benefit of this will arrive when we have a version of the NetScaler VPX that can use this platform capability (later this year).

StorageLink Site Recovery.  You’ve got a secondary site where you want to replicate all your virtual machines in case disaster strikes your primary site.  StorageLink Site Recovery simplifies the process of setting up this replication and recovering virtual machines in the DR site. Check the StorageLink HCL for arrays that initially support Site Recovery.

Citrix License Server integration.  Paid versions of XenServer now require a Citrix License Server.  Here’s what you need to know:

1. The Free version of XenServer continues to use the file-based activation process, so a license server isn’t required if you are using Free XenServer.

2. Unlike with prior versions of XenServer, licensing is enforced.  Before you upgrade any existing 5.x systems to 5.6, verify that you have the right number of licenses allocated to you via your mycitrix.com account. Note that there is a 30 day grace period after an upgrade, which gives you plenty of time to get your License Server set up.

3. In addition to the existing Windows-based License Server, we’re making a License Server virtual appliance available as well.  Just import it, run through a short configuration, and use a browser to upload your license files.

For more information on 5.6 licensing, see CTX125301.

Was anything removed from the product in 5.6?

Not much.  The legacy Linux P2V tool in the installer is gone, though it wasn’t of much use any more since it only worked for very old distros. We’ve also dropped Debian Etch (4.0) support since it no longer receives security updates.  Those of you who look closely might find that the new “Demo Linux VM” template is, shall we say, eerily similar to Debian Etch.  It’s not recommended for production use, and we have this solely because so many of you told us you liked the built-in Linux distro for testing and demonstration purposes.

The Remote Desktop Services Deployment Guide for Windows Server 2008 R2 is now live on the Download Center and on TechNet.  This guide is intended for use by system administrators and system engineers who are responsible for deploying the role services and features for Remote Desktop Services for the Virtual Desktop Infrastructure (VDI) environment. It provides detailed guidance for deploying a Remote Desktop Services design that is preselected by you, an infrastructure specialist, or a system architect in your organization.

The Terminal Services Deployment Guide for Windows Server 2008 is now live on the Download Center and on TechNet.  This guide is intended for use by system administrators and system engineers who are responsible for deploying the role services and features for Terminal Services. It provides detailed guidance for deploying a Terminal Services design that is preselected by you, an infrastructure specialist, or a system architect in your organization.

Microsoft released App-V 4.6 for RDS Whitepaper.

This whitepaper discusses the benefits, configurations and considerations when planning a Microsoft® Windows Server® Remote Desktop Services solution with Microsoft Application Virtualization.

You can download the whitepaper here.

Microsoft just announced the immediate availability of Microsoft App-V 4.5 SP2:

App-V 4.5 Service Pack 2  provides the latest updates to Microsoft Application Virtualization 4.5 code line. This is the first time the team has delivered via Windows Update App-V 4.5 SP2 introduces:

• Enhanced failover protection or disaster recovery of your virtual application infrastructure: App-V data-store failover protection enables administrators to quickly recover from disasters and/or recycle servers for maintenance.
• Enable highly available application infrastructure: App-V 4.5 SP2 load balanced management servers can now leverage SQL server mirrored data-store to support high availability scenarios for line of business applications; with automatic failover protection not available with the previous versions of App-V.
• Data replication is now possible across geography: this enables organizations to recover from site wide failures faster.
• App-V 4.5 SP2 clients can now deploy Office 2010.

To learn more you can get all the details straight from the source.

Consider the following scenario:

• A Microsoft Application Virtualization (App-V) application is published to or advertised on a client computer of Microsoft System Center Configuration Manager 2007 R2.
• The Allow virtual application package advertisement option is enabled in System Center Configuration Manager 2007 R2.

In this scenario, System Center Configuration Manager 2007 R2 removes all virtual applications that are published to the client without any warning.

This behavior is by design but to learn more and see what your options are check out the KB article below:

KB983255: App-V applications are removed when the “Allow virtual application package advertisement” option is enabled in System Center Configuration Manager 2007 R2

Microsoft is increasing its marketing effort in promoting its VDI platform since a few months now.

Microsoft published a guide to help Deploying Remote Desktop Connection Broker with High Availability.

This guide is intended for IT professionals, and tells how to configure Remote Desktop Connection Broker in a failover cluster. The configuration provides users with access to personal virtual desktops or virtual machines in a virtual desktop pool through RemoteApp and Desktop Connection.

You can find it here.

Here you can find some useful resources to plan and design Citrix environments.

The following resources provide a best-practices based approach to designing virtualization environments based on Citrix XenApp and XenDesktop technologies:

• Windows XP Optimization Guide for Virtual Desktops
  Description: If Windows XP is still your desktop operating system of choice and it is going to be used within a virtual desktop environment, you need to optimize it appropriately. The optimizations will help deliver a better user experience and greater scalability on the hypervisor of choice (XenServer, Hyper-V, or ESX).
• XenDesktop Modular Reference Architecture
  Description: The architecture explained within this white paper is a recipe for creating a scalable XenDesktop environment using any required FlexCast option. This reference architecture discusses how to configure the controllers, imaging layer, application layer and the desktop layer.
• High-Availability for Desktop Virtualization – Reference Architecture
  Description: In environments where desktop virtualization is a critical business resource, it is imperative that the solution remains available even if a component or data center is lost. This reference architecture looks at all levels of the entire XenDesktop solution, and provides an architecture for creating a highly-available solution.
• High-Availability for Desktop Virtualization – Implementation Guide
  Description: Implementing a desktop virtualization solution oftentimes requires an investigation and implementation of the high-availability options. This white paper provides step-by-step instructions for enabling high-availability in XenDesktop within a single site and across multiple sites.
• Virtual Applications or Virtual Desktops
  floirDescription: Trying to decide between virtual desktops and virtual applications is oftentimes challenging. By understanding the core expectations and requirements for each delivery method helps make this decision easy. This white paper focuses on the decision and how to identify the most appropriate type of delivery solution.
• Networking topics, including Global Server Load Balancing- it’s like never having to worry about datacenter failures again.

Microsoft announced that Microsoft Application Virtualization will be available as a new family in WSUS.  According to the WSUS Product Team blog:

We will be adding a new product family to your WSUS server –Microsoft Application Virtualization.  The Microsoft Application Virtualization product family will include updates for all Microsoft Application Virtualization products. It will include a variety of update types, e.g. service packs, optional updates, critical updates and security updates.  Additionally, Microsoft Application Virtualization updates will be available through Microsoft Update and the Microsoft Update Catalog http://catalog.update.microsoft.com.

A new product category will be added to your WSUS server under the Microsoft Application Virtualization family, entitled Microsoft Application Virtualization 4.5. The Microsoft Application Virtualization 4.5 category will allow all classifications of updates to be offered to the Microsoft Application Virtualization 4.5 product.  You will see this new category when new updates are available for this product.

For all the details you can check out the source here

Citrix has realesed XenClient after a long period of beta testing.

Here you can find more information about it: http://www.citrix.com/English/ps2/products/product.asp?contentID=2300325

XenClient is a high-performance, bare-metal hypervisor that enables users to run multiple instances of an operating system simultaneously, side by side, and in complete isolation. XenClient uses the same core technology as Citrix® XenServer®—a proven technology widely acknowledged as the fastest and most secure virtualization software available. To ensure the highest levels of performance for the user, XenClient builds on Intel® vPro™ hardware virtualization technology.

Citrix® XenClient™ enables virtual desktops to go. Desktop virtualization is rapidly being adopted as the best way to deliver Windows® desktops to business users. Now, organizations can extend the benefits of desktop virtualization to mobile users, for new levels of portability and security. With XenClient, laptop users can take multiplevirtual desktops with them and work from anywhere, anytime.

Intel IT conducted an internal technology evaluation to determine how using the most up-to-date hardware and software, such as Intel® Xeon® processor X5570 and Microsoft Windows 7, affects server and network utilization as well as the performance of streamed and virtual hosted desktop (VHD) compute models. This study followed a previous investigation, published in 2008, that compared streaming and VHD.1 Evaluation indicates that streaming provides better server loading and a more positive overall user experience with new Intel® Xeon® processors.

Click here for read the paper

Here you can find some interesting points:

• For basic office productivity applications, systems based on dual-core processors with streaming provided a 26 percent better WorldBench 5 performance benchmark score than VHD.
• Streaming server utilization was consistently low. Streaming used about 1 percent of the processor while VHD used from 10 to 70 percent or more for up to 40 PCs.
• A richer graphical user interface(GUI) with more features in Microsoft Windows 7 contributed to higher cumulative network traffic for both streaming and VHD, up to a 57 percent increase in traffic for 20 users.
• Using WorldBench 5 tests as the primary indicator, local computing using the latest technology provided the best user experience.