Lab Validation Report - china.emc.com · This ESG Lab report documents the hands-on testing ... and increase consolidation ratios ... on a VMware host in the test bed environment

Lab Validation Report EMC PowerPath/VE

Automated Path Optimization for VMware Virtual Environments

By Vinny Choinski, Senior ESG Lab Analyst, and Mike Leone, ESG Lab Engineer

April 2012 © 2012, The Enterprise Strategy Group, Inc. All Rights Reserved.

Lab Validation: EMC PowerPath/VE 2

© 2012, The Enterprise Strategy Group, Inc. All Rights Reserved.

Contents

Introduction .................................................................................................................................................. 3 Background ............................................................................................................................................................ 3 EMC PowerPath/VE ................................................................................................................................................ 4

ESG Lab Validation ........................................................................................................................................ 6

Getting Started ....................................................................................................................................................... 6 Performance Advantage ......................................................................................................................................... 9 Availability with Visibility ...................................................................................................................................... 11

ESG Lab Validation Highlights ..................................................................................................................... 14

Issues to Consider ....................................................................................................................................... 14

The Bigger Truth ......................................................................................................................................... 15

Appendix ..................................................................................................................................................... 16

All trademark names are property of their respective companies. Information contained in this publication has been obtained by sources The Enterprise Strategy Group (ESG) considers to be reliable but is not warranted by ESG. This publication may contain opinions of ESG, which are subject to change from time to time. This publication is copyrighted by The Enterprise Strategy Group, Inc. Any reproduction or redistribution of this publication, in whole or in part, whether in hard-copy format, electronically, or otherwise to persons not authorized to receive it, without the express consent of The Enterprise Strategy Group, Inc., is in violation of U.S. copyright law and will be subject to an action for civil damages and, if applicable, criminal prosecution. Should you have any questions, please contact ESG Client Relations at 508.482.0188.

ESG Lab Reports

The goal of ESG Lab reports is to educate IT professionals about data center technology products for companies of all types and sizes. ESG Lab reports are not meant to replace the evaluation process that should be conducted before making purchasing decisions, but rather to provide insight into these emerging technologies. Our objective is to go over some of the more valuable feature/functions of products, show how they can be used to solve real customer problems and identify any areas needing improvement. ESG Lab's expert third-party perspective is based on our own hands-on testing as well as on interviews with customers who use these products in production environments. This ESG Lab report was sponsored by EMC.



Introduction

This ESG Lab report documents the hands-on testing of EMC PowerPath/VE for VMware virtual environments and validates the business and performance benefits of PowerPath/VE load balancing and path management when compared with VMware native path management. The report focuses on the performance, ease of management, and failover and recovery capabilities of PowerPath/VE.

These tests were designed to simulate the real-world SAN conditions that organizations encounter every day, and they were conducted using common tools to highlight the potential impact on application, SAN, and storage performance. While these test results represent what a user might experience, actual results will vary depending on the data center configuration.

Background

Server virtualization is on the rise, driven by the positive results that organizations are achieving, the increasing benefits as virtual deployments expand, and the growing popularity of cloud computing. As ESG research discovered, early on in their virtual machine (VM) experience, organizations benefit primarily from data center cost reduction. But as virtual deployments expand, they gain higher-level benefits such as improved provisioning, data protection, application availability, and IT automation. It makes sense that organizations plan to increase their virtual deployments given these experiences. When IT managers were asked recently what their organizations’ most important IT priorities would be over the next 12 to 18 months, 30% indicated that they planned to increase their use of server virtualization (see Figure 1).1 Often, this includes extending virtualization to production and business-critical workloads—not just IT-focused applications.

Figure 1. Top-Ten IT Priorities for 2012 and Beyond

Source: Enterprise Strategy Group, 2012.

1 Source: ESG Research Report, 2012 IT Spending Intentions Survey, January 2012.

22%

22%

23%

24%

25%

27%

27%

29%

30%

30%

0% 5% 10% 15% 20% 25% 30% 35%

Deploying a "private cloud" infrastructure

Mobile workforce enablement

Desktop virtualization

Data center consolidation

Business continuity/disaster recovery programs

Information security initiatives

Manage data growth

Major application deployments or upgrades

Improve data backup and recovery

Increased use of server virtualization

Which of the following would you consider to be your organization's most important IT priorities over the next 12-18 months? (Percent of respondents, N=614, ten responses

accepted)

http://www.enterprisestrategygroup.com/2012/01/2012-it-spending-intentions-survey/



However, virtualizing more applications and increasing consolidation ratios can create contention for data paths, which can then affect application performance and availability. Manually mapping data paths across the environment becomes extremely difficult in these expansive, hyper-consolidated environments. The dynamic nature of virtual implementations, the move to virtualize more production applications, and the increasing service-level expectations of users conspire to make I/O bottlenecks even more problematic.

EMC PowerPath/VE

In the same way that server virtualization creates a sharable pool of computing resources, and networked storage creates a sharable storage pool, EMC PowerPath/VE delivers dynamic multipathing capabilities that form a pool of data paths. Built on the gold-standard PowerPath application for physical hosts, PowerPath/VE provides automated data path management and failover and recovery for VMware vSphere (and Microsoft Hyper-V) environments to produce predictable, scalable, consistent information access across Fibre Channel, iSCSI, and FCoE environments. (Note: Though PowerPath/VE supports Hyper-V, the focus of this report is on PowerPath/VE for VMware vSphere.)

Because PowerPath/VE resides in the hypervisor (below applications/guest operating systems and above the HBAs and storage), it can support heterogeneous servers, guest operating systems, networks, and storage environments. PowerPath/VE for vSphere is integrated with VMware vCenter Server and Update Manager as well as vSphere auto-deploy and stateless licensing capabilities, and operates effectively with any raw storage devices, volume managers, file systems, and applications.

EMC PowerPath/VE is available standalone and as a key component in VCE Vblock Infrastructure Platforms: preconfigured virtualization solutions combining best-of-breed technologies from VMware, Cisco, and EMC. Vblock Infrastructure Platforms make it easier for organizations of all sizes to implement cloud strategies.

Automated failover and recovery. PowerPath/VE automates data path failover and recovery to eliminate business interruption from failures or errors, without manual mapping. If a path error occurs, data is redirected to the next best path and the load is rebalanced across all paths (see Figure 2). When the failure is resolved, that path is returned to the available pool. Intelligent, dynamic testing of inactive paths enables faults to be preemptively discovered and paths automatically removed from service; upon resolution of the fault condition, the failed path is automatically returned to the pool without disrupting operations or requiring manual intervention.



Figure 2. PowerPath/VE Overview

Intelligent load balancing. PowerPath/VE enables IT to assign all data paths to all devices and let PowerPath/VE adjust path usage according to I/O loads. It does not simply distribute I/O evenly among all paths; instead, it uses statistics and algorithms to identify the optimal path for the workload. For example, while many solutions simply pass I/O along in a round-robin or pre-determined arrangement, this can lead to clogged paths and bottlenecks. Path A may be next in line, but if it has a heavy I/O load pending, it will not be the best-performing path. PowerPath/VE considers pending I/O, size and type of I/O, as well as last path used, so that each I/O request obtains optimal performance. As a result, no path becomes overloaded if others have underutilized bandwidth.

Because PowerPath/VE adjusts I/O path usage in response to the I/O loads emanating from each VM, it can operate effectively in virtual environments that use dynamic tools such as VMware vMotion, Distributed Resource Scheduler, and High Availability configurations. In addition, its architecture supports multi-tenant deployments for private and public clouds; in multi-HBA and CNA environments, I/O traffic from user-designated SAN LUNs may be dedicated to specific HBAs or CNAs to provide dedicated bandwidth.

PowerPath Viewer provides the ability to view hosts, host groups, LUNs, individual LUN paths, and buses across the entire virtual as well as physical environment from a single GUI. Notifications are delivered to update IT on device status.

PowerPath/VE automatically optimizes data access and application performance, simplifying path management so that organizations can virtualize more applications and increase consolidation ratios without creating I/O bottlenecks. PowerPath/VE delivers:

Automated multipathing and I/O load balancing Seamless path failover and recovery Path optimization designed to enhance application performance Proactive fault detection to prevent interruption to data access Reduced complexity End-to-end I/O visibility across the virtual infrastructure

PowerPath/VE has been extensively tested by EMC E-Lab to operate effectively in hundreds of different deployments on various hardware platforms. It has proven its reliability under many types of conditions including clustered environments, thin provisioning, VM partition mobility, various fault insertions, non-disruptive upgrades, SAN boot environments, and more.



ESG Lab Validation

ESG Lab performed hands-on evaluation and testing of PowerPath/VE at an EMC facility in Cambridge, Massachusetts. Testing was designed to demonstrate the ability of PowerPath/VE to automatically and dynamically balance SAN path traffic for performance optimization while providing path failover-level availability for virtual environments. Also of interest were ease of deployment and infrastructure visibility. Testing was conducted using industry-standard tools and methodologies.

Getting Started

Getting started with PowerPath/VE centered on conducting a review of the test bed used for the subsequent test scenarios as well as installing the actual software. ESG Lab did a physical walk-through of the data center supporting the test bed, identifying the server, storage, and SAN components used in the validation. The walk-through was followed by an actual PowerPath/VE installation on a VMware host in the test bed environment.

ESG Lab Testing

ESG Lab first reviewed the test bed configuration, collecting supporting component information required to render a high-level overview diagram. As shown in Figure 3, the test bed consisted of two VMware host servers (shown on the upper-left of the diagram) SAN connected to an EMC Symmetrix VMAX storage array (shown on the upper-right side).

Figure 3. Validation Test Bed

The two VMware host servers were both running vSphere 5.0. Each host server was connected to the SAN with a QLogic dual-port HBA. For testing, one VMware host was configured with the native NMP multipathing set to the



Round Robin policy. The second VMware host was configured with PowerPath/VE multipathing set to SymmOpt for the EMC Symmetrix VMAX array. Five Windows 2008 servers, (identified as Jamming Servers) are shown on the bottom-left of Figure 3. Each jamming server is running an Iometer backup workload. The jamming servers are designed to demonstrate the impact of common infrastructure-related SAN traffic on production applications. The function of the jamming servers is to generate more I/O on one of the four storage ports. This kind of imbalance is frequently seen in SAN configurations in which multiple hosts are accessing shared network and storage components.

Next, to verify the easy and well-integrated install process, ESG Lab ran through the deployment process. The Lab used the VMware Update Manager (VUM) method to install PowerPath/VE. The PowerPath software bundle was downloaded from the EMC Powerlink website in the form of a zip file. The offline package zip file was then extracted and saved to a local file share.

As shown in Figure 4, ESG Lab used the import patches option in Update Manager to upload the PowerPath/VE package to the VMware vCenter configuration. ESG Lab then created a host extension baseline for the new package (called PPVE5.7) as shown in the middle of Figure 4. The baseline was then attached to one of the VMware hosts in the test bed environment following steps 1 and 2 shown at the bottom of Figure 4.

Figure 4. Update Manager Integration Process

ESG Lab simply powered down the VMs associated with the VMware host. The Lab then put the host in maintenance mode and attached the host extension PowerPath/VE baseline. Once complete, the host was taken out of maintenance mode, and the associated VMs were powered back on. It should be noted that VMs do not have to be shut down during an installation or upgrade in an ESX cluster when VMware Update Manager is used (or scripted via CLI). VMs are usually vMotioned to other nodes in the cluster. The ESX host is restarted in the process, though.

Finally, ESG Lab used Update Manager to confirm a successful installation of PowerPath/VE to the selected VMware host. As shown in the bottom-left of Figure 5, PowerPath was successfully attached to the host at IP address (192.168.157.38) in the test bed. The green circle in the host compliance section to the right of the figure also



indicates a successful installation. It should be noted that EMC enables the PowerPath download to be run in trial mode at no cost for 45 days for those wishing to evaluate its features.

Figure 5. Compliance Verification

Why This Matters

Growing virtual server deployments can quickly become complex as the number of VMs grows to hundreds and thousands. As administrators strive to keep the environment performing optimally, software solutions that must be installed in several locations and require multiple reboots for different storage devices and configurations create headaches. Complex implementations can make it difficult to extend virtualizations to production applications.

ESG Lab validated that EMC PowerPath/VE was easy to install and configure. Using VMware Update Manager, ESG Lab integrated it in VMware vCenter as a host extension and easily attached PowerPath/VE to vSphere hosts. The tight integration with vCenter created a centralized, easy-to-manage platform for deploying PowerPath/VE in the test environment.



Performance Advantage

Performance advantage is the process of applying simulated real-world workloads on a virtual host running PowerPath/VE and a virtual host running native NMP and auditing the results. Application performance, especially in highly consolidated virtualized environments, often suffers in the presence of resource contention. Application workloads such as Exchange databases, OLTP, and file systems are IOPS-intensive; performance depends on the number of IOPS that the data path can handle. Other application types such as backup, decision support, Exchange logs, and video-on-demand are throughput-intensive; performance depends on the data path’s ability to handle large file sizes. ESG Lab compared the performance of PowerPath/VE with the performance of the VMware native

NMP for these workloads.

ESG Lab Testing

ESG Lab tested simulated IOPS- and throughput-intensive workloads.2 Iometer was used to generate the primary server workloads while the jamming hosts executed backup-reading tasks.

ESG Lab generated file serving, Exchange database, and 8K OLTP workloads on both servers, one configured with PowerPath/VE and the other with NMP. At the same time, five other Windows servers generated backup reading workloads to create resource contention. A common source of resource contention often occurs during backup windows. Most backup applications are configured with dedicated devices that tend to load or make busier specific SAN paths. PowerPath/VE determined that the busier jamming paths, while active and available, were not optimal and automatically redirected I/O to better paths. The NMP server, in contrast, retained its round robin-distribution and continued to place I/O on the clogged data path.

As shown in Figure 6, PowerPath/VE handled 25% more IOPS versus NMP for 8K OLTP workloads, 17% more for File Server, and 22% more for Exchange DB data.

Figure 6. Performance Comparison, IOPS-intensive Workload

The same tests were administered using decision support, Exchange log, and video-on-demand I/O loads on the primary servers. These simulate common occurrences such as users downloading large files that can degrade performance across the infrastructure. Figure 7 shows the results of these tests. The PowerPath/VE advantage over NMP was 24% for decision support, 143% for Exchange logs, and 138% for video-on-demand.

2 Note that application workload simulation often provides a clearer performance picture than actual customer workloads, which are likely to be affected by other data center characteristics.



Figure 7. Performance Comparison, Throughput-intensive Workload

Finally, ESG Lab tested the response time for Exchange database I/O on both the PowerPath/VE- and NMP-configured servers. The response time was 18% faster with PowerPath/VE than with the native NMP.

Figure 8. Performance Comparison, Exchange Database Response Time



Why This Matters

The workload consolidation that server virtualization creates means that more I/O requests are competing for data paths; this resource contention can be exacerbated by increasing the number of virtualized applications, increasing consolidation ratios, and VM mobility. Accompanying these challenges are the everyday data path issues that can occur regardless of server virtualization, such as faulty paths, HBA errors, cable degradation, etc. As more production applications become virtualized, the performance and availability impacts of resource contention become even more problematic.

ESG Lab found that PowerPath/VE with intelligent, automated load balancing outperformed the VMware-native multipathing set to the Round Robin policy for IOPS- and throughput-intensive workloads as well as Exchange database response time, resulting in less SAN congestion.

Availability with Visibility

Availability with visibility is the combination of the redundantency built into PowerPath in conjunction with the detailed view of the SAN infrastructure provided by PowerPath Viewer. PowerPath/VE provides automated failover and recovery in the event of a SAN path fault and provides intelligent load balancing of SAN paths based on traffic load for virtual environments. PowerPath Viewer is a no-charge utility that provides centralized, remote health monitoring through a graphical user interface (GUI) with a detailed view of the SAN infrastructure, for both physical and virtual environments.

ESG Lab Testing

ESG Lab leveraged PowerPath Viewer to highlight the availability capabilities of PowerPath/VE as well as demonstrate the detail views of the SAN environment that are provided by the viewer application. As shown in Figure 9, the two ESX servers that are part of the validation test bed are in the middle of the host monitoring tab. Figure 9 shows both hosts in a healthy state with a call-out box indicating full access to all LUNs and all paths to the devices alive and well. The right side of Figure 9 also shows the healthy HBA ports and VMAX storage devices for one of the two ESX hosts.

Figure 9. Test Bed with Full Path Access



Next, the Lab introduced a fault by disabling a port on one of the SAN switches in the test environment. This fault was selected to mimic the loss of an lpfc module in a SAN environment. PowerPath Viewer was then used to quickly drill down and isolate the affected components.

As shown in Figure 10, a warning message was displayed for a host (lcg040) in the test environment. Hovering over the warning message indicated that LUN access for that host was in degraded mode and that only half of the paths to the storage were still alive.

A quick view of the HBA from the affected host indicated a connectivity problem on port one. Further exploration from the host LUN view confirmed lost access to device (C0:T0:L0) on one of the paths from the host to the array.

Figure 10. Test Bed Degraded Access

As shown in Figure 11, detailed information from the path and bus alerts tabs confirmed the same condition identified via the higher-level host view. With a single HBA failure, the path alerts window displays the severity as “Warning” because PowerPath Viewer recognizes that I/O to the LUN is still available through another path. Overall, the path state is degraded. If there were no paths to the LUN, the severity would be “Critical.” The bus alerts window displays the severity as “Critical” because, without the HBA, the connection between the host and any zoned storage ports is unavailable.



Figure 11. Path and Bus Alert Detail

Finally, as shown in Figure 12, the host-side command line interface was used to view the fault from the host perspective. ESG Lab compared the results from the degraded host with that of the healthy host in the test environment. The analysis with PowerPath Viewer allowed the Lab to quickly isolate the problem to the host side of the SAN and ultimately to the switch port itself.

Figure 12. Command Line Host View of Fault Condition

Why This Matters

As additional workloads are virtualized and consolidated, failures along data paths have a magnified impact, interrupting more business processes. Business-critical workloads must be protected from these interruptions to ensure that service levels are met, and to enable organizations to gain the full range of virtualization benefits.

ESG Lab disabled a Fibre Channel switch port and validated the ability of PowerPath/VE to failover to another path automatically. PowerPath Viewer enabled ESG Lab to monitor the effects of this path failure across the environment, including both path and bus alerts. The ease of identifying path failures enables IT to resolve them more quickly to maintain service levels.



ESG Lab Validation Highlights

ESG Lab found the PowerPath/VE deployment process was easy to manage and well integrated with VMware vCenter. Using VMware Update Manager created a single-pane-of-glass installation paradigm that becomes more important as a virtual environment grows. We were pleased to find the package download had a 45-day no-charge trial period for those interested in testing the functionality of the product before purchasing it.

ESG Lab validated that the intelligent load-balancing performance benefit of PowerPath/VE provided an all-around gain for the validation test bed virtual environment. We measured substantial improvement in every category, including IOPS, throughput, and response times.

We confirmed that the inherent availability functionality of PowerPath/VE works flawlessly. We introduced a failure in the SAN environment and observed that our workload ran undisrupted on the surviving SAN paths.

The Lab found that the no-charge PowerPath Viewer tool greatly reduced the time and effort required for isolation and remediation of a fault condition. We leveraged the detailed visibility provided by the monitoring application to quickly isolate a simulated fault during the validation testing. Additionally, we were able to monitor PowerPath multipathing supporting a Windows environment from the same screen, giving credence to the claim that PowerPath Viewer can monitor both physical and virtual environments from a single pane of glass.

Issues to Consider

When making major changes to your SAN environment, it is important to remember to update your PowerPath/VE configuration. Failure to do so may impede your ability to take advantage of performance and availability gains. Without a configuration update, PowerPath/VE considers these changes unintentional, and they will not be incorporated into the environment in order to avoid affecting running applications. Major changes include:

o Adding or removing a Fibre Channel switch o Adding or removing an HBA o Zoning changes o Adding or removing logical devices

Currently, PowerPath Viewer only supports e-mail notification for problem alerting. ESG Lab believes that adding SNMP capabilities to the product would create great flexibility for integrating its features with existing client-monitoring infrastructures. PowerPath/VE can send SNMP traps through VMware vCenter alarm console today.



The Bigger Truth

If organizations want to expand their virtual deployments, leverage private and public clouds, increase the virtualization of business-critical workloads, and deliver the service levels that contemporary users demand, automated management, failover, and recovery of data paths will be required. ESG’s most recent IT spending intentions survey indicates that increased use of server virtualization remains the top priority, as it has been for three years; in addition, 74% of organizations surveyed plan to increase spending on cloud computing.3 As organizations take on these deployments, maintaining the integrity of data paths across the environment must be part of the plan.

Organizations need a highly available pool of resources, but manually mapping data paths for thousands and even tens of thousands of VMs is simply untenable. IT cannot efficiently manage I/O and map applications with bandwidth in growing and hyper-consolidated virtual deployments. Path management solutions are available, but native solutions may not deliver the best performance. VMware NMP provides a few path management options, but without any intelligence and without the performance.

In contrast, EMC PowerPath/VE not only provides automated failover and recovery of data paths, but it also optimizes I/O placement to deliver the best performance possible. Because it looks at I/O characteristics as well as array coding and queue depth, PowerPath/VE can select the best path for each I/O request, even with the shifting landscape of virtual machines. Its proactive fault identification keeps degraded paths out of circulation until faults are resolved, and PowerPath Viewer enables IT to monitor status and performance across the environment. While ESG Lab testing focused solely on the virtual environment, the same PowerPath Viewer and tool set are used for PowerPath Multipathing, so that details of data paths in both physical and virtual environments can be monitored together.

Looking to the future, the world is changing; storage arrays and servers are becoming smarter at mapping hot data to the best performing cache and storage locations. It is becoming ever more critical that path management solutions use intelligent optimization to leverage these features. PowerPath/VE is ready to take advantage of and complement innovations like EMC VFCache server flash and FAST VP as the EMC E-Lab works to qualify support for more and more third-party storage solutions.

While the budget stranglehold of the past few years is letting up, improving IT efficiency remains in vogue. Server virtualization can deliver high-level benefits as deployments expand—as long as IT organizations attend to the nitty-gritty details. You can virtualize all the applications you want, but if your data paths are not up to the job of handling consolidated workloads, it may do more harm than good. EMC PowerPath/VE delivers high-performing, highly available data path management to support growing virtual server and cloud deployments in almost any IT implementation, without adding management complexity.

3 Source: ESG Research Report, 2012 IT Spending Intentions Survey, January 2012.

http://www.enterprisestrategygroup.com/2012/01/2012-it-spending-intentions-survey/



Appendix

Table 1. ESG Lab Test Bed

Software

EMC PowerPath/VE Version 5.7

EMC PowerPath Viewer Version 1.0 SP2

Windows Version 2008 R2 (64 bit)

VMware vSphere Version ESXi 5.0

Iometer Version 2008.06.18

Servers

(2) Dell Servers Model R710 VMware: vSphere ESXi 5.0 Emulex LPe12002 HBAs

(5) Dell Servers Model R710 Windows 2008 Emulex LPe12002 and QLogic QLE2562 HBAs

SAN

(1) Brocade 1U Switch Model DS-300B Firmware Version 6.1.0c

(1) Brocade 2U Switch Model DS-5300B Firmware Version 6.1.0c

Storage

(1) EMC VMAX Array Microcode 5875.198.148 RAID-5 LUNs

20 Asylum Street | Milford, MA 01757 | Tel: 508.482.0188 Fax: 508.482.0218 | www.enterprisestrategygroup.com

Documents

Lab Validation Report - china.emc.com · This ESG Lab report documents the hands-on testing ... and increase consolidation ratios ... on a VMware host in the test bed environment