SAP virtualization projects are on the rise, but on the whole they remain far from mature, so companies embarking
on SAP virtualization initiatives shouldn't expect a quick fix when support issues arise, according to experts.
The problem is that each SAP user company is different, and there simply isn't enough documentation or plain old hands-on experience to quickly remedy the growing number of SAP virtualization issues. Whether a company needs virtualization-related assistance from SAP or a virtualization infrastructure provider like VMware, problems often have to be recreated before answers can be found, and this can be a time-consuming process.
"[Technology professionals] need to understand that [SAP virtualization] is not quite at the level of pioneering, but it's still early and there isn't an enormous amount of experience out there," said Jim Shepherd, senior vice president of research with Boston-based AMR Research Inc. "If they run into problems and reach out for support, there aren't going to be a lot of folks that [can immediately identify the problem]."
Analysts and technology professionals point out, however, that there are some practical steps firms can take to ensure that virtualization support calls either go as smoothly as possible or become unnecessary in the first place.
Bad infrastructure means bad problems
First off, remember that companies can avoid a lot of SAP support calls by having a well designed infrastructure, said Rick Scherer, a virtual architect with the San Diego Data Processing Corporation (SDDPC), a nonprofit that handles IT operations for San Diego's municipal government and city workers.
For the last two-and-a-half years, Scherer has served as the lead on a massive SAP virtualization project designed to get all of the city's various ERP systems running on SAP in a virtualized environment.
"Right now, the city of San Diego has all of its processes run on different machines spread throughout the city. The water department has its own finance system, the treasury department has its own finance system, and the police have their own financial system, etc.," Scherer explained. "We have the goal of creating one management point for all of that."
In his own experience and in talking with industry peers, Scherer has found that most virtualization support issues can be traced back to infrastructure problems.
"One scenario that I've heard is that a customer deploys a Tier 1 application like SAP on a virtual machine, and the performance isn't that great," he said. "Come to find out that they put all of their data on one set of discs and [as a result they] hit an I/O contention that they normally wouldn't hit in a physical world. That's because, in the physical world, you would separate your OS from your database from your backup, and so on."
The moral is that it's important for organizations to build a virtual environment the same way they would build a physical environment, with logical and physical separation of high I/O discs.
"Deploying virtually isn't truly any different from deploying physically," Scherer said. "You need to build redundancy, reduce all the bottlenecks that you can, separate your data, set priorities for CPU and memory concerns, and that's pretty much it."
Know your hardware and software performance characteristics
Companies also need to be aware of the performance characteristics of the SAP applications they're seeking to virtualize, according to Tony Iams, senior vice president and senior analyst with Rye Brook, N.Y.-based Ideas International Inc. Those performance characteristics are likely to vary by situation.
Users need to find out the demands of their SAP workloads in terms of CPU, memory, I/O and network resources. Understanding those demands will help organizations avoid any "unpleasant surprises" when they begin using virtualization to consolidate an SAP environment.
"[Companies should also] make sure they understand the support terms from SAP, and that may vary by platform," Iams added. "Find out if there are any differences in support on VMware versus HyperV versus Citrix or some other hypervisor."
Users can also head off support calls and ensure a solid virtualization infrastructure by being cognizant of the limitations that hardware platforms have in virtualization environments, said Chris Wolf, a senior analyst with Midvale, Utah-based Burton Group.
"This is especially critical for SAP deployments just [as it is for] any other multi-threaded enterprise application that you might try to run in a virtual machine [VM]."
In addition, make sure that the virtualization software chosen for SAP virtualization projects supports hardware-assisted memory virtualization. Wolf said the technology provides a massive performance improvement for many multi-threaded applications and is especially crucial for SAP virtualization environments. Virtualization software vendors that support hardware-assisted memory virtualization include VMware and Citrix.
"Make sure the hardware platform supports it as well," Wolf said. "That would be a hardware platform that supports AMD Rapid Virtualization Indexing technology. With Intel, that's called Extended Page Table or EPT [technology]."
Overall, he said, making sure that you have the right virtualization infrastructure and avoiding support issues means doing due diligence with sizing and making sure that the hypervisor and the hardware below the hypervisor are going to meet the particular performance needs of the SAP application.
"Using an earlier, a legacy or a cheaper hardware platform to run your virtual infrastructure might work today, but once you start to virtualize Tier 1 applications, you're going to find that the performance needs don't meet expectations," Wolf said. "If you have the right hardware underneath and the right hypervisor, there's very little that you can't virtualize right now."
Pick the right management tools
The addition of a virtual machine hypervisor to the IT technology stack comes with a significant new layer of complexity. Users need to manage the hypervisor's interactions with the operating system, the hardware and the application. Finding the right virtualization management tools can help, Iams said, and there are plenty to choose from.
"You have more levels of interaction now, and one way to deal with that is to have management tools that span more than one or two levels of the stack," he said. "When something is wrong, that would make it easier to find out whether the problem is in the operating system or the hardware or the hypervisor."
A key advantage that Microsoft touts is the ability of its system management tools to work with the hypervisor as well as the operating system running inside the virtual machine. In comparison, Iams said, VMware tools don't have that much insight into what's going on inside the virtual machine.
The analyst said that third-party or independent virtualization management companies are too numerous to list, but one that has been getting a good amount of attention of late is Portsmouth, N.H.-based vKernel Corp.
"They take a time-based view of resource consumption," Iams said, "allowing you to plan for the evolving demand on virtual resources using 'what if' scenarios, etc."