Dell Desktop Virtualization Solutions. Simplifying desktop virtualization with the production-ready Dell Integrated Solution Stack (ISS)

Dell Desktop Virtualization Solutions Simplifying desktop virtualization with the production-ready Dell Integrated Solution Stack (ISS)

Contents Executive summary 3 Introduction 4 Designing a production-ready solution stack 5 Designing and validating the Dell ISS 6 Producing multiple Dell ISS configurations 7 Helping organizations select a Dell ISS configuration or create a custom design 15 Reducing the complexity of desktop virtualization 16 For more information 16 Table of Figures Figure 1: Built on Citrix XenDesktop software, the Dell ISS integrates multiple software and hardware components to deliver virtualized desktops 8 Figure 2: Organizations also can select a Dell ISS based on VMware View software 9 Figure 3: The Dell ISS Enterprise and Enterprise Plus hardware components 12

Executive summary For many organizations, implementing desktop virtualization in an enterprise environment can be a long and challenging project. IT groups must select and integrate multiple components, configure the solution for the current number of users and existing workloads, and also build in the flexibility for change. Any design and deployment mistakes can easily add costs and risks. The Dell Desktop Virtualization Solutions (DDVS) business unit created the Dell Integrated Solution Stack (ISS) to help reduce the time, complexity, risks, and costs of implementing desktop virtualization in enterprise production environments. Thoroughly tested and validated, the Dell ISS goes beyond the generic, lab-based reference architectures available today, providing a production-ready Virtual Desktop Infrastructure (VDI) solution that takes into account a full range of real-world enterprise challenges and requirements. The Dell ISS is built on Citrix XenDesktop software but is also available with VMware View software. This paper provides an in-depth look at the Dell ISS that will be valuable for any organization contemplating desktop virtualization. The paper: Highlights key real-world requirements that desktop virtualization solutions should address Traces the Dell ISS development process, in which the DDVS team defined typical user types and workloads, designed the solution, and conducted a comprehensive validation process that spanned 50,000 person-hours Details the software, hardware, storage, and network components used for both the Enterprise and Enterprise Plus configurations of the Dell ISS, including industry-leading products from Dell, VMware, Citrix, Microsoft, and Juniper Explains how the solution uses tiered storage to deliver strong performance and data protection Describes how the solution s modular approach facilitates predictable, process-driven deployment and scaling 3

DDVS can help organizations select the right version of the Dell ISS or design a customized desktop virtualization solution through a multiphased process. By working with DDVS and implementing the Dell ISS, organizations can reduce risks and costs involved with desktop virtualization projects while accelerating the time to value. Introduction Organizations are turning to desktop virtualization as a way to help enhance worker mobility and flexibility, improve security, simplify IT management, and cut costs. As many have learned, however, implementing desktop virtualization can be a complex undertaking. IT groups need to select and integrate multiple hardware and software components, correctly configure the solution for the right number of users and the right mix of workloads, prepare the solution for a range of enterprise IT challenges, and ensure that the solution has the scalability for change and growth. Several hardware and software vendors have developed reference architectures to help simplify the adoption of desktop virtualization. Reference architectures can offer a valuable starting point for desktop virtualization, but many of them available today have significant limitations. These reference architectures were developed in small, controlled lab environments that lack real-world infrastructure components and are insulated from the challenges organizations might face in production environments. They represent a generic recipe for desktop virtualization, but they require extensive modification through a costly services engagement to be ready for customer implementation. In many cases, these reference architectures also lock organizations into working with a single vendor for multiple infrastructure components instead of providing a solution with best-of-breed hardware and software. 4

Dell Desktop Virtualization Solutions (DDVS) has designed the Dell Integrated Solution Stack (ISS) to help reduce the time, complexity, risks, and costs of implementing desktop virtualization in enterprise production environments. The result of 50,000 person-hours of validation work, the Dell ISS presents a thoroughly tested solution that mitigates risks and provides the reliability and scalability organizations require for desktop virtualization in real-world environments. Combining the Dell ISS with the rich portfolio of Dell services and support enables organizations to achieve the benefits of desktop virtualization rapidly and cost effectively. This paper identifies real-world issues that a solution stack should take into account, examines the components of the Dell ISS, explains Dell design decisions, and demonstrates why the Dell ISS will be the right solution for many organizations. Designing a production-ready solution stack To successfully implement desktop virtualization, organizations need more than the generic starting point that many reference architectures provide. They need a production-ready solution stack that takes into account a full range of real-world enterprise challenges and requirements, including: High availability The solution stack should incorporate high-availability and redundancy features to help ensure that desktops and user data are ready for users at all times. Network bandwidth The solution stack design should address the impact of desktop virtualization on the network. What bandwidth is required for the target number of concurrent users? Is the network prepared for spikes in traffic that result from simultaneous virus updates or boot storms, when numerous users log in at the same time? Multiple workload definitions The solution stack must be prepared to accommodate workloads covering a mix of desktop users, from task workers to advanced knowledge workers with varying personalization and performance requirements. 5

Future proofing Given the time and investment required for implementing desktop virtualization at the enterprise level, a solution stack must provide the flexibility for change without requiring major overhauls. Scalability The solution stack must be designed to accommodate growth simply and cost-effectively. Designing and validating the Dell ISS The Dell ISS was created to reduce the complexity of designing and deploying desktop virtualization solutions. Rather than offering a generic, lowest-common-denominator reference architecture, Dell has built a scalable, production-ready solution stack that can address a variety of potential IT challenges. Validated using multiple, real-world workloads, the Dell ISS includes industry-leading technology from Dell, VMware, Citrix, Microsoft, and Juniper that has been tested and tuned to provide the right balance between performance and cost. The process of developing the Dell ISS began by defining industry-standard desktop user types and workloads. Typically, organizations will have a mix of several workloads in their environment: Basic users Task workers, ranging from call-center agents to nurses, who are often required to enter information, complete forms, or do repetitive tasks. These workers require fast access to a small number of applications and do not need a personalized desktop environment. Standard users Workers who use e-mail, typical office productivity applications, and Web browsing for research or training. With these workers, there is minimal image personalization required. Premium users Advanced knowledge workers whose office applications are distinctly configured. These workers might be creating graphics, editing presentations, or creating other content. The image for these users requires extensive image personalization. 6

With the typical users defined, the DDVS team designed the Dell ISS including software, servers, storage, and networking and began a comprehensive validation process. To validate the Dell ISS, the Dell Data Center Solutions Group developed a testing methodology to simulate real-work desktop workloads. The team used scripts to run typical workloads from each type of user. Each script ran on multiple configurations for eight hours to emulate a true workday. The Dell team used both sequential testing (on a single host) and parallel testing (on the full ISS solution stack) to validate individual components, determine the scalability of the entire stack, establish proper sizing, and ensure that results would accurately reflect real-world situations. After running workloads, the tool provided scores that indicated the quality of the end-user experience, based on the host processor and memory utilization plus network and storage performance. These scores helped define the number of users that a host can support before performance degradation is experienced. Additional tools were used to analyze the infrastructure performance along with the end-user experience. Through that lengthy process, Dell established high-water marks for the number of sessions each configuration could handle while maintaining sufficient performance. Producing multiple Dell ISS configurations The Dell ISS uses the Virtual Desktop Infrastructure (VDI) model, in which virtual desktops are hosted as virtual machines (VMs) in a consolidated infrastructure and then delivered over a network to end-user client systems. Built on Citrix XenDesktop 5 software, the stack integrates an array of software components for delivering desktops, hosting configuration and session information, and provisioning desktops (see Figure 1). Citrix XenDesktop Controller The controller authenticates users, assembles virtual desktop environments, and brokers connections between users and their virtual desktops. 7

Citrix XenDesktop Database This Microsoft SQL Server database hosts configuration and session information on a resilient platform. Citrix Provisioning Services With this component, organizations can reduce storage requirements by using a single desktop image to create multiple virtual desktops on one or more servers in the data center. Citrix Virtual Desktop Agent Installed on virtual desktops, the agent allows direct Independent Computing Architecture (ICA) connections between virtual desktops and users endpoint devices. Citrix Desktop Receiver This application runs on the endpoint, enabling the device to connect to a virtual Microsoft Windows XP, Windows Vista, or Windows 7 desktop running on a server. VMware vsphere VMware vsphere server virtualization software helps consolidate hardware by partitioning resources of the host servers. To increase customer choice, Dell also offers a version of the Dell ISS based on VMware View 4.5 desktop software. The VMware version includes analogous software components (see Figure 2). ISS XenDesktop cluster resource pools Windows XP Windows XP Management virtual machines Windows 7 Windows 7 Windows 7 Windows 7 XenDesktop Delivery Controller XenDesktop Provisioning Server XenDesktop Web Interface XenDesktop License Server Citrix NetScaler VPX VMware vcenter vcenter data PVS data XenDesktop data End-user profile End-user document Microsoft SQL and File Dell Product Group vdesktop pool Management pool Cluster pool VMware vsphere 4.1 Hypervisor MS Server 2008 R2 Cluster Dell PowerEdge or server Figure 1: Built on Citrix XenDesktop software, the Dell ISS integrates multiple software and hardware components to deliver virtualized desktops 8

ISS View cluster resource pools Windows XP Windows XP Management virtual machines Windows 7 Windows 7 Windows 7 Windows 7 View Connection Broker vcenter with View Composer vcenter data View data End-user profile End-user document Microsoft SQL and File Dell Product Group vdesktop pool Management pool Cluster pool VMware vsphere 4.1 Hypervisor MS Server 2008 R2 Cluster Dell PowerEdge or server Figure 2: Organizations also can select a Dell ISS based on VMware View software Whether organizations choose a Citrix- or VMware-based solution stack, they can select from Enterprise and Enterprise Plus configurations of the Dell ISS. The Enterprise configuration will be the right fit for organizations supporting between 500 and 1,000 users. The Enterprise Plus configuration can serve as the foundation for a dense, high-availability solution to support more than 1,000 users. Both configurations offer modular scalability that enables organizations to expand the desktop virtualization solution to many more users while protecting their investments. Enterprise configuration The Enterprise configuration uses Dell PowerEdge rack servers equipped with Intel Xeon processors. The servers offer 125 percent greater memory capacity and more integrated I/O than the previous-generation server, helping to increase the performance and density of VMs running on the servers. The servers also feature the Unified Server Configurator (USC), which helps simplify provisioning functions such as system deployment, system updates, hardware configuration, and diagnostics. 9

For storage, the Enterprise configuration uses the Dell EqualLogic PS6500E iscsi SAN. This SAN features dual 1 GbE controllers for full redundancy. Available with up to 48 7,200 rpm SATA II drives in 500 GB, 1 TB, or 2 TB capacities, the SAN can provide up to 96 TB of capacity in a single array. It can be scaled up to 1.5 PB in a single SAN group, giving organizations the ability to expand the amount of system images, user data, and backup data without having to replace the SAN. The configuration also incorporates a Dell PowerConnect J-EX4200 48-port, top-of-rack 1U switch. Virtual Chassis technology helps lower management costs and reduce administrative burdens by enabling organizations to connect up to 10 switches as a single logical device, supporting up to 480 10/100/1000BASE-T server access ports and an additional 20 GbE or 10 GbE uplink. Tiering Each configuration uses a tiered storage approach to provide strong performance and data protection. The tiering structure follows best practices established by Citrix, VMware, and Dell regarding where certain types of data should reside and which types of storage should be used, given particular I/O requirements. With tiered storage, the configurations can create the right balance of user functionality and operational efficiencies. For the Enterprise configuration, the operating system (OS) images reside locally on the server disk drives. When a user logs in, the desktop is created dynamically for that user by drawing on the master image residing on the server. 10

The SAN provides the Tier 2 storage, which includes user data such as documents, user profile information, and preferences. User data is layered on top of the OS image. Separating the OS from user data helps organizations sustain excellent desktop performance, avoid issues, and reduce help-desk incidents. In non-virtualized desktop environments, performance could slow over time as a result of slight OS modifications and add-ons. With the Dell ISS, users receive fresh, pristine desktop images generated from the master image each time they log in. Tier 3, also located on the SAN, is an optional tier for backup and recovery. Administrators can replicate OS images and user documents on Tier 3. For conducting long-distance replication, organizations can create a fourth tier with a second storage environment. Modular approach The Dell ISS uses a modular approach, which provides scalability in blocks of 1,000 to 1,500 users depending on user workload ratios. This modularity facilitates a predictable, process-driven deployment that enables organizations to quickly, easily, and cost-effectively scale their infrastructures to accommodate a larger number of users. ISS sizing definitions are the result of extensive validation work by Dell. These definitions specify a validated number of users per host and per modular unit for each type of typical desktop workload. The Enterprise ISS base unit includes: Two Dell PowerEdge physical management servers in a VMware vsphere management resource pool for management services, which reside in virtual servers. Two physical cluster host servers in a Microsoft Windows Server 2008 R2 cluster resource pool for database and file services. Two top-of-rack Dell PowerConnect J-EX4200 switches 11

One Dell EqualLogic PS6500E iscsi SAN for Tier 2 storage (user data) and optional Tier 3 storage (backup and recovery) each SAN can support up to four modular units Five Dell PowerEdge VM servers, with local storage, in a VMware vsphere cluster The base unit can support up to 12 virtualization hosts. If an organization needs more than 12 hosts, administrators can simply add another unit, quickly and cost-effectively, without having to re-architect the solution. Tier 3 Storage Optional tier for backup and recovery EQL EQL Tier 2 Storage User documents, profile information, and preferences EQL EQL Tier 1 Storage OS images XVS XVS Enterprise M1000e Enterprise Plus Figure 3: The Dell ISS Enterprise and Enterprise Plus hardware components Enterprise Plus The Enterprise Plus ISS configuration builds on the Enterprise configuration, adding high-availability capabilities and active workload migration with VMware vmotion capabilities, and facilitating greater infrastructure density to accommodate a large number of users without increasing the infrastructure footprint. This configuration uses Dell PowerEdge half-height blade servers in a PowerEdge M1000e chassis. The chassis is designed to provide redundancy and eliminate single points of failure. 12

Dual independent management controllers help to ensure that administrators can continue their management tasks even if one controller fails. The chassis also uses two Dell PowerConnect M6220 and M8024 chassis network switches for redundancy. The M6220 provides redundant 20 GbE uplinks for desktop and management session traffic. The M8024 provides redundant 40 GbE uplinks for iscsi and vsphere management traffic as well as vmotion traffic. Like the rack servers in the Enterprise configuration, the blade servers are equipped with Intel Xeon processors to provide the performance and large-scale memory bandwidth required for server and desktop virtualization. As an organization adds more physical servers to the desktop virtualization infrastructure, blade servers can help maximize server density. If an organization were to use five 2U rack servers, it would have a total of 10 processors. By comparison, the 10U M1000e chassis can house 16 half-height blade servers, with a total of 32 processors, providing more than three times the density. Blade servers also can help keep costs under control. With VMware virtualized server hosts, organizations would typically require six to eight network connections to provide necessary redundancy and throughput. Using blade servers in a chassis, organizations can reduce costs by minimizing the number of network cables and decreasing management burdens. To facilitate high availability, the Enterprise Plus configuration stores the OS images on a Dell EqualLogic PS6010XVS hybrid array which combines solid-state drives (SSDs) and SAS drives rather than on local server drives. When planned maintenance is required, administrators can simply use VMware live migration capabilities to move users to new physical hosts in the cluster and remap that new server to the PS6010 hybrid array. Users can continue to work without disruption. By contrast, keeping the master image on a server would require users to save their work, log off, and then log back in during planned maintenance events. 13

The use of both SSDs and SAS technologies, meanwhile, helps balance performance and costs while also avoiding potential challenges such as boot storms. The PS6010XVS automatically places data on the appropriate disk technology after analyzing I/O and performance patterns. The PS6010XVS might use the SSDs for desktop initialization, for example, to avoid performance issues that could arise during boot storms. For Tiers 2 and 3, the Enterprise Plus configuration uses the Dell EqualLogic PS6510E iscsi SAN. This SAN features dual 10 GbE controllers and the same capacity as the PS6500E SAN used for the Enterprise configuration. Using 10 GbE connectivity for the Enterprise Plus configuration provides the bandwidth required to support a larger number of users. It also enables administrators to use bandwidth for management tasks and VMware vmotion live migration of virtualized machines. The Enterprise Plus configuration uses a Juniper EX4500 40- port top-of-rack switch. Virtual Chassis technology enables administrators to connect up to 10 switches as a single logical device, supporting up to 480 10/100/1000BASE-T server access ports plus an additional 20 GbE or 10 GbE uplink. Each Enterprise Plus ISS modular unit includes: One M1000e blade enclosure Two management servers in a VMware vsphere cluster Two cluster servers in a Microsoft Windows Server 2008 R2 cluster Five VM host servers in a VMware vsphere cluster Two Tier 1 EqualLogic PS 6010XVS storage arrays One Tier 2 EqualLogic PS 6510E SATA array (which can support up to four modular units) As with the Enterprise base unit, the Enterprise Plus base unit can support up to 12 virtualization hosts and two EqualLogic PS 6010XVS arrays. Beyond that number, organizations would need additional storage, networking, and management hosts. 14

Helping organizations select a Dell ISS configuration or create a custom design DDVS can help organizations select the right version of the Dell ISS for their specific needs through a multiphased process. First, the Dell team introduces the organization to different technologies and discusses the organization s motivations and goals for desktop virtualization. The Dell team gathers information about the existing infrastructure and uses the Dell Economic Impact Assessment (EIA) tool to help IT build a business case for desktop virtualization. Using a data collection tool, the Dell team then creates a digital footprint of the IT environment. The tool helps determine the number of users for each type of workload, the enduser applications used, the application response times users experience, and the compute and network resources needed. The tool also analyzes the network environment to evaluate the capacity to accommodate the workloads. The team uses that data to recommend a validated ISS configuration. Alternatively, organizations can select to design a custom solution with DDVS. Dell Services can implement the chosen desktop virtualization design and validate the solution. Organizations can then choose to manage the solution themselves or outsource management to Dell. 15

Reducing the complexity of desktop virtualization Implementing a desktop virtualization solution can be a complex undertaking. The Dell ISS can help simplify the process, mitigate risks, reduce costs, and accelerate the time to value. Drawing on best-of-breed software and hardware solutions, this productionready solution stack is designed to address real-world challenges and is validated using actual workloads, in everyday conditions. With modular scalability, the Dell ISS can be expanded easily as organizations add employees and realize the tremendous potential benefits of desktop virtualization. For more information For more information about the Dell Integrated Solution Stack, contact your Dell representative. To learn more about the Dell methodology for designing and implementing desktop virtualization, begin by visiting: www.dell. com/us/corp/p/d/flexible-computing/desktop-virtualizationworkshop.aspx 2011 Dell Inc. All rights reserved. Reproduction of this material in any manner whatsoever without the express written permission of Dell Inc. is strictly forbidden. For more information, contact Dell. Dell, the DELL logo, and the DELL badge, EqualLogic, PowerConnect, and PowerEdge are trademarks of Dell Inc. Other trademarks and trade names may be used in this document to refer to either the entities claiming the marks and names or their products. Dell Inc. disclaims any proprietary interest in trademarks and trade names other than its own. June 2011 16