I D C O P I N I O N S I T U A T I O N O V E R V I E W. Sponsored by NEC. Kazuhiko Hayashi May 2013

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1 IDC Japan, Kudan-Kita, Chiyoda-ku, Tokyo ; Tel: FAX: W H I T E P A P E R R e l i a b i l i t y I m p r o v e m e n t I s K e y t o S e r v e r V i r t u a l i z a t i o n F a u l t - T o l e r a n t S e r v e r s G e t A n o t h e r L o o k Sponsored by NEC Kazuhiko Hayashi May 2013 I D C O P I N I O N Server virtualization is becoming more common. No longer the province just of large companies with large datacenters, it is spreading to smaller operators, branch offices, and international offices. Today it has become common practice to virtualize servers and use a number of logical servers to run systems. Conversely, server virtualization using standard x86 servers runs the risk of a failure in one server spreading to multiple business systems running on that server. Relatively large datacenters can provide backup systems in many different forms when failures occur, but small and medium-sized enterprises and sales offices with fewer servers have limited options. This study examines the benefits of fault-tolerant servers as an effective means for improving availability in the virtualized environments of user companies. S I T U A T I O N O V E R V I E W According to IDC forecasts, shipping volumes in the Japan server market will be flat in the range of 530,000 to 570,000 units from 2012 to This is because of the higher performance and larger capacity of servers at present. General-use x86 servers can now have 10 to 20 core processors and more than 100-gigabyte (GB) memory, which have led to greater consolidation of servers. Another factor encouraging the consolidation of servers is the large number of products that can easily create virtualized environments at a low cost. While the Japan virtualized server market forecast indicates that physical server shipping volumes will be flat in the range of 530,000 to 570,000 units from 2012 to 2016, the number of virtualized logical servers is expected to grow from 1.25 million in 2012 to 2.29 million in As a result, the server virtualization rate is forecasted to increase steadily from 18.7% in 2012 to 35.5% in 2016 (Figure 1). Meanwhile, in the global market, the x86 server virtualization rate reached 21.4% in 2012 and is forecasted to continue to grow in the future. As can be seen in Figure 1, the number of virtualized servers will be more than four times the physical server shipping volume in However, the virtualization of servers means that the growth in the number of logical servers will not translate into higher physical server numbers. With management unable to see an increase in the number of servers managed directly by IT departments, IT departments will have difficulty in seeking increase in management staff. In a survey of companies using x86 servers conducted by IDC in 2012, more companies responded that their IT headcounts were smaller compared to those in 2010 or earlier than companies that responded that their IT headcounts had increased. The highest percentage of companies responding that headcounts had declined was in the range of 10 to 99 employees. The steady increase in the number of logical servers therefore means increasing workloads for the IT departments and staff (Figure 2).

2 Unit (X 10,000) (%) F I G U R E 1 J a p a n V i r t u a l i z e d S e r v e r S h i p p i n g V o l u m e, Number of physical servers Number of logical servers Virtualization rate Note: "Virtualization rate" refers to the ratio of servers applying virtualized environments to total physical server shipping volume. Source: IDC Japan, 2013 F I G U R E 2 C h a n g e i n H e a d c o u n t f o r I n f o r m a t i o n S y s t e m O p e r a t i o n s, M a i n t e n a n c e, a n d M a n a g e m e n t, b y T o t a l C o r p o r a t e H e a d c o u n t Overall (n = 888) employees (n = 97) employees (n = 355) ,000 or more employees (n = 436) Note: Created from information in 2012 Survey of Japan x86 Server Support: Impact on Vendor Selection (IDC #J , published March 2012) Source: IDC Japan, March Increased No change Decreased (%) 2 # IDC

3 It should be noted that the ease with which virtualized environments can be introduced not only increases the workload on IT departments but may also extend the time required from system failure to system recovery. As the number of logical servers on a single physical server increases, so does the extent of the damage to operations in the event of a failure, because the failure of one physical server will ultimately result in failures at larger numbers of logical servers. IDC, therefore, believes that ensuring adequate availability will require more emphasis in system design when virtualized environments are introduced to servers. V i r t u a l i z e d E n v i r o n m e n t s R e q u i r e H i g h A v a i l a b i l i t y Recent years have seen server virtualization extend from companies with large datacenters to smaller workplaces and small and medium-sized enterprises with fewer employees. The number of servers used, however, has remained at minimal levels, though there has been an increase in the number of business applications implemented on virtualized servers. Among the reasons for the increase is the emergence of server OSs like Windows and Linux that incorporate virtualization as a standard feature. On the other hand, one must also be aware of the risk of running multiple logical servers in a virtualized environment because multiple applications running on a single physical server mean that when a server hardware failure occurs, the failure can spread to multiple applications. Large systems with relatively high numbers of servers employ redundancy among multiple servers and "high availability" (HA) software to switch servers in the event of failure and maintain the availability of important applications. Smaller workplaces with fewer servers and smaller systems, however, find it difficult to install and manage multiple servers to ensure availability. According to IDC's 2012 Japan Systems Infrastructure/DBMS Market User Survey (IDC #J , published July 2012), virtualized environment users most commonly indicate that "quickly identifying and analyzing the causes of failure" is a key issue in the operations management of virtualized systems (Figure 3). In particular, the managers of smaller systems with fewer servers in operation identified this as the biggest issue they confront. This indicates that server failure is the greatest worry for system managers when creating virtualized environments for smaller workplaces, small and medium-sized enterprises and international offices. The fact that physical failures on virtualized servers can spread into the failure of multiple logical servers means that large amounts of time are required to restore systems when there are few IT managers or they are not located close by. One of the crucial factors to take into account when installing systems that implement virtualization is that system design should minimize failure factor beforehand. Minimizing server failure factors requires the assurance of overall hardware and system availability. There are a number of conventional approaches to assuring server availability, but core corporate systems that must run 24 hours a day, 365 days a year generally run on high-availability mainframes or large UNIX servers. For less expensive x86 servers, one common method is to cluster multiple servers with a master server monitoring them and software to switch slave servers in the event of failure (HA functions). Another is to use fault-tolerant servers (hereinafter "FT servers") that employ hardware redundancy. While there are some user companies that use the cloud and entrust the cloud services providers to ensure adequate availability, the potential for systems to stop due to failures in the cloud itself must also be considered IDC #

4 F I G U R E 3 I s s u e s i n V i r t u a l i z e d S y s t e m s O p e r a t i o n s M a n a g e m e n t Unable to quickly identify and analyze causes when failure occurs 24.4 Inability to back up virtual machine Complex license management for applications in virtualization environments Unable to centrally monitor utilization of physical environments and virtualization environments Difficulty managing multiple hypervisors Increase in the number of virtual machines increases management workload Insufficient support for virtualization environments from vendors and SIers Unable to centrally manage physical environments and virtualization environments Difficult to add, change, and delete virtual machines No effective security measures in virtualization environments Lack of extensibility because of poor capacity planning No improvement in performance because of inadequate resource management Inappropriate patching of guest OSs and applications Virtual machine HA/failover doesn't work Others (%) Notes: Multiple responses were allowed. Created from 2012 Japan Systems Infrastructure/DBMS Market User Survey (IDC #J , published July 2012) Source: IDC Japan, July 2012 A d v a n t a g e s o f F a u l t - T o l e r a n t S e r v e r s i n S e r v e r V i r t u a l i z a t i o n While there are many approaches to ensuring availability in virtualized environments, for standard systems based on x86 servers, the common approach is either a cluster system that combines multiple general-purpose servers and HA software, or the use of FT servers, which is the subject of this study. Cluster systems create virtualized environments as a combination of multiple general-purpose servers and HA software, with software to perform failover to a spare server in the event of server failure. FT servers are built with redundant hardware, and the server itself has failure monitoring functions that are active at all times. Should a failure occur, the monitoring function automatically isolates the failed unit to ensure that the system continues to operate (Figure 4). The general practice for HA software-based cluster systems is to prepare a standby server that is mutually connected to the currently operating servers. The HA software 4 # IDC

5 monitors operating servers, and when one experiences a failure, that software switches processing to the standby server to minimize system downtime and improve availability. In this case, the time required from failure to switchover to the standby server is usually something on either side of several minutes to several tens of minutes, during which time service is halted. By contrast, FT servers have structures automatically to isolate failed units when a failure occurs, and there is no suspension of service. This makes them particularly suited for workplaces with few server managers and to plant production lines that are most vulnerable to short-term system stoppages. For applications that require higher availability, it is possible to use a combination of FT servers and HA software to build systems that emphasize availability. F I G U R E 4 C o m p a r i s o n o f F a u l t - T o l e r a n t S e r v e r s a n d C o n v e n t i o n a l S e r v e r s ( H i g h A v a i l a b i l i t y C o n f i g u r a t i o n ) Virtualization systems in FT servers No downtime for virtual machine Restoration complete In service In service In service Module #1 Module #2 Synchronization 1) Failed module is isolated when failure occurs (instantaneous) Virtualized system using ordinary servers (HA configuration) Switchover begins Isolation of failed module System down (several minutes to several tens of minutes) 2) Synchronization resumes after replacement of failed module Failed module replacement Switchover complete In service Service suspended Service resumed Suspension Failure 1)Timeout of less than 20 seconds 2) Determination of takeover host requires tens of seconds 3) Restart of virtual machine: Several minutes to several tens of minutes Switchover Restart launch completed Repair/ replacement Source: NEC, 2013 FT servers employ redundancy on all major server components, and are equipped with features for mutual synchronization and monitoring (Figure 5). When a failure occurs, the failed module is automatically isolated and the system continues to operate at functioning parts. As a result, even physical failures can be addressed without system services being suspended. Fully redundant hardware means that server monitoring and operations can continue during maintenance and replacement, but also that costs are high in comparison with conventional servers. Because of this, they were considered to be enterprise servers before virtualization was introduced IDC #

6 F I G U R E 5 F a u l t - T o l e r a n t S e r v e r C o n f i g u r a t i o n Note: Two servers are contained in a single frame and synchronized with each other to produce the equivalent of one server. Source: NEC, 2013 However, people have begun to reconsider the value of FT servers in recent years as configuration of multiple logical servers on a single physical server has become possible thanks to the introduction of virtualization, increased CPU-cores, and improved server performance. FT servers entail higher per-server costs because of hardware redundancy. However, the installation and operation costs per logical server decline by adopting virtualization technology to configure multiple logical servers on a single server and when multiple applications are installed and run. One of the reasons why FT servers are getting another look is that virtualization enables multiple applications to be implemented on a single FT server, thereby significantly reducing the cost per logical server. FT servers have the advantage of easy maintenance in the event of failure as well as an operational advantage of automatically switching over when a failure occurs. Therefore, they provide a value that is commensurate with cost. For user companies, there is a need to improve overall system availability when system failures can seriously impact applications and by extension, negatively affect operations. It will be important to make use of both HA software-based clusters and FT servers depending upon the system's size and management structure. Server hardware with better reliability and availability is particularly important in situations in which the number of servers is as low as is possible, for example, in offices, branch offices, and international offices that lack full-time IT managers, or in plants where production lines cannot be stopped. Workplaces such as these cannot depend on dedicated IT managers to manage complex systems, and require management that does not need much knowledge of virtualized environments. The advantage of FT servers is that once the system is built in the virtualized environment, the failed module is automatically isolated in the event of a hardware failure to maintain ordinary operations. Even after failure, there is no need to make complex system settings (unlike HA software-based cluster systems), and it is possible to replace and restore failed components easily while the system is still operating. This means that FT servers minimize the negative effects on operations even with a small number of system managers. 6 # IDC

7 N E C ' S H I G H - R E L I A B I L I T Y V I R T U A L I Z A T I O N P L A T F O R M F e a t u r e s a n d A d v a n t a g e s o f t h e F a u l t - T o l e r a n t " E x p r e s s / f t S e r v e r " NEC has offered x86 server-based "Express5800/ft Server" FT servers since In November 2005, it increased its collaboration with joint developer Stratus (USA), and established a partnership for developing, producing, and financing new hardware and software. The company uses a proprietary redundant chipset LSI to control FT servers. This LSI is the heart of the FT server and the mechanism that controls redundant hardware that is the hallmark of FT servers. It performs advanced synchronization, server management, failure detection and isolation. The company modularized all major components except the backplane to enable quick replacement in the event of a hardware failure; modules can be replaced while the system is in operation. The Express5800/ft Server contains two modules that are equivalent to one physical server. These modules are synchronized mutually to monitor operations via the "GeminiEngine" redundant chipset. The hardware is redundant, but the software does not recognize which servers are operating; from the perspective of the system, this is equivalent to operating a single piece of hardware. Because of this, with existing OSs and applications, the Express5800/ft Server has the following features that mask the perception of FT server peculiarities: Exists as a single server without the network being aware of redundancy Is perceived by OSs and application software as a single server, not requiring special processing or dedicated applications for operation Handles server operations and maintenance in the same way as a single server It should be noted, however, that there are some restrictions on usable devices because drivers that support Express5800/ft Server are required for the network, discs, fibre channels, USB, video display, and other I/O interfaces. One of the features of the Express5800/ft Server is that failed units can be quickly replaced without shutting down the system in the event of failure. The biggest advantage is that a system with high availability can be introduced without users being aware that special hardware has been installed, because existing OSs and applications can be used "as is." At NEC, the Express5800/ft Server has been shown to be designed to be able achieve five 9s (99.999%) availability; the installation of this server can be attain extremely high hardware utilization. For that reason, the company's FT servers can be found in operation in numerous plants and workplaces where high availability is required, including those overseas. C h a l l e n g e s F a c i n g N E C FT servers have mechanisms that automatically isolate failed hardware in virtualized environments, thereby ensuring availability and facilitating operations management. However, such utility has not adequately become widespread to users. IDC believes that NEC and other server vendors must explain the advantages of FT servers in virtualized environments, their differences from other solutions, and their pros and cons in operations management to user companies in a way that can be easily understood. It will also be necessary to present the benefits of FT servers in virtualized environments by indicating breakeven points, including running costs in 2013 IDC #

8 comparison to other high-availability solutions, and by providing specific operational examples. C O N C L U S I O N S u m m a r y Server virtualization rates are growing in Japan and other countries. IDC forecasts that in 2016, the number of virtualized servers will be more than quadruple the number of physical servers in Japan, and that server integration and virtualization will accelerate even more in the future. Some servers are installed in smaller workplaces and international branches where IT managers are unable to respond quickly in the event of failure. A failure in one server, therefore, could spread to all virtualized servers and seriously damage operations. Improving server availability is an extremely important point in system design. There are many different ways to improve availability, but among them, the installation of FT servers is particularly effective in environments where system managers are unable to respond quickly. The introduction of virtualization significantly reduces the installation cost per logical server and provides benefits that exceed server hardware costs. As these benefits become clearer, FT servers are being reconsidered for the high levels of availability and the ease of failure management that they bring to virtualized environments. R e c o m m e n d a t i o n s t o U s e r C o m p a n i e s The common trend is to introduce virtualized environments and integrate servers to reduce server hardware costs. However, virtualized servers run multiple applications, and failure in a single server has the potential to spread to numerous applications. Server failure response and the management of multiple virtualization servers are becoming more complex, and such increasing complexity translates into higher workloads for system managers. Many different methods have been proposed for assuring high availability in virtualized environments; some suited for large-scale enterprise systems, others for smaller workplaces. The use of FT servers is one effective solution that reduces the load on system managers. Indeed, FT servers are extremely effective in workplaces and international branches that have few servers and lack dedicated system managers, and also in plants where production lines cannot immediately be shut down. The virtualization of FT servers reduces the cost per logical server while assuring high availability and facilitating systems management. IDC believes that the time has come for user companies to compare FT servers that conventionally had been thought to have high hardware costs and to be used for enterprises, assuming the introduction of virtualization, and to take a look at the indices including the loss of opportunities caused by failures, and the ease of management. 8 # IDC

9 C o p y r i g h t N o t i c e This report is furnished as an IDC product. For details concerning this report and IDC services contact IDC Japan Sales (Tel: ; jp-sales@idcjapan.co.jp). IDC retains all copyrights to figures and tables explicitly identified in this report as "Source: IDC Japan" and "Source: IDC." Copyright 2013 IDC Japan. Unauthorized Reproduction Prohibited IDC #