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How to troubleshoot common VDI issues

VDI administrators must be adept at troubleshooting various VDI issues. Sufficient planning can prevent some, but IT should be prepared to deal with a few common issues.

When organizations run into serious issues with their VDI deployments, it can undermine many of the advantages.

Fortunately, there are several steps IT teams can take to troubleshoot these issues and, in some cases, address them before they become major problems. Organizations just getting started with VDI should perform proper planning to prevent VDI issues.

Common VDI issues

Despite the many promises that come with VDI, organizations often encounter issues related to performance, complexity, security, costs and user experience.

  1. VDI users are having a poor desktop experience.

Nothing can cause a VDI project to fail like a substandard user experience. This can result from inadequate compute or storage resources, inability to access file shares, WAN connectivity issues, improper application design, client device problems or other factors. Regardless of the cause, the results are the same: lower productivity and a disgruntled workforce.

  1. VDI desktops are subject to ongoing performance issues.

Oftentimes performance issues lie at the heart of a poor user experience, but there can be many causes. The virtual desktops might have inadequate processor or memory resources, the storage system might suffer from disk contention, or a network segment might not have the adequate bandwidth. It's also possible that desktop applications have memory leaks, or antivirus software is overwhelming the system. The problem may be that IT is running more desktops than the infrastructure can reasonably support.

For example, application stability can be problematic with VDI. Applications experience the same issues as PCs; an application starts to use a lot of CPU or memory, and the desktop becomes unresponsive. The big difference is, with a VDI deployment, that affects the user's ability to see the desktop because the remote display protocol gets starved of CPU.

  1. VDI introduces security and compliance risks.

Contrary to popular belief, virtual desktops are susceptible to a wide range of attacks and security issues, just like their physical counterparts. At the same time, many VDI deployments support work-from-home and BYOD programs, enabling connectivity across connections and devices that IT can't monitor or control like on-premises systems.

If end users are also using these devices for personal activity, such as browsing risky websites, attackers could gain access to the devices and subsequently the virtual desktops, making it possible to steal or destroy sensitive corporate data.

  1. VDI management is overly complex.

One of VDI's biggest promises is to simplify desktop administration; however, maintaining the environment is just as important. Tasks such as balancing resource allocation, managing desktop images, moving virtual machines or ensuring compliance can all contribute to greater complexity.

To complicate matters even more, IT must also maintain the hardware, patch software, ensure availability and reliability, and scale infrastructure as business requirements change, while still ensuring the delivery of high-performing virtual desktops.

  1. VDI costs exceed the planned budget.

Although centralizing desktop management can help lower costs, VDI still relies on a fault-tolerant infrastructure to deliver reliable desktop services, and such an infrastructure requires the professional expertise to keep systems running and troubleshoot issues.

At the same time, IT teams must replace equipment as it ages or fails and accommodate changing business strategies that require infrastructure reconfigurations. They might also need to provision and manage client devices, even if they're only thin clients. All it takes is one unexpected event to send the budget into orbit.

  1. VDI constrains users' needs.

In a VDI environment, IT usually provides the user with a very locked environment. Organizations want their users' desktops to be the same, so IT often uses Windows Group Policy and security settings to constrain users so they can't install their own applications.

This is a double-edged sword because users find it more difficult to solve problems by finding their own applications. The IT team must be responsive to end users' requests for applications, particularly early on in a VDI deployment, to learn what the users actually need.

VDI troubleshooting tips and steps

Troubleshooting VDI should be as much a proactive process as a reactive one. With either approach, however, IT can take several important steps to help streamline the troubleshooting process and address infrastructure issues before they become critical.

  1. Understand the virtual desktop environment and its resources.

Multiple teams might have been involved in setting up the VDI platform, or some team members might have moved on. Chances are, the individuals now troubleshooting issues had nothing to do with the system's initial deployment. Before they can effectively identify and address problems, they must understand the infrastructure inside and out. For example, they need to know the number and type of servers, the databases being used, where they're hosted, the desktop domain structure, the services used, communication protocols and a variety of other details.

  1. Maintain visibility into the VDI environment.

IT requires both high-level and granular insight into the infrastructure, its applications and virtual desktops. Administrators require ongoing end-to-end visibility and real-time insights into all VDI-related operations. Without this type of monitoring, they cannot get at root causes or proactively address potential issues before they've taken down the system.

Most VDI platforms include debug information via native monitoring platforms that can provide deep visibility. Event logs will tell IT admins a great deal about what's going on, but some of the logs can be very verbose. There may be hundreds of records going through every minute, particularly in a large-scale environment. IT needs to parse those logs and turn them into useful information. For this process, Splunk, a tool for managing logs, can be helpful, and it integrates with desktop virtualization products.

  1. Properly allocate resources.

Improperly allocated resources are often the root cause of VDI issues. If application stability is a frequent problem, IT can create a dual-processor VM rather than a single processor. If an application saturates one CPU core, there's a second core available that the remote display protocol can use. This is a best practice in VMware View if an organization works with graphically intensive applications. It decreases the number of desktops IT can provision per virtualization host, but if it means that the desktops are always available, IT may choose to do this for a subset of users who need high-CPU load applications.

  1. Use the right troubleshooting tools.

IT must use the right tools to effectively troubleshoot and isolate issues. Although multi-platform generic tools might be useful to some degree, administrators need tools that are proven effective for their specific VDI platform and that can help them identify and address issues.

Admins should also use a tool that correlates to the specific problem at hand. For example, if admins are having user profile management issues, then they should use a profile management tool such as Liquidware Labs' ProfileUnity. It helps with problems around one-off applications -- apps that are used by only a small number of users -- because it has some functionality for user-installed applications. VMware admins can handle Windows roaming profiles with VMware Persona Management, which performs a periodic upload so IT doesn't need a clean logoff to get the profile data onto the profile share.

A tool should be able to get at a problem's root cause, rather than focus only on the symptoms. It should also be able to advise technicians on how to fix problems as efficiently as possible. In some cases, a tool might use historical data to provide insights into issues, or it might include built-in intelligence for more effectively troubleshooting problems.

  1. Get feedback from desktop users.

Virtual desktop users can be an invaluable source of information when troubleshooting VDI issues. From these users, infrastructure technicians can learn about possible error messages, if the problem has been experienced by multiple users or how often the issue occurs. Technicians can also gather information about VDI client versions, what endpoints are used, when the problem takes place, if it occurs at certain times of day or other relevant information.

Additionally, IT teams should understand which applications users need access to. Application virtualization can also be extremely helpful in this regard. It works well for applications that are used by a small number of users. If an organization has four or five staff members who need access to a payroll application, then virtualizing that application is better than carving off four or five VMs to dedicate to the payroll team.

  1. Narrow down the focus.

Administrators troubleshooting VDI issues should try to narrow down their focus as quickly as possible, using information from system monitoring, user feedback and any other sources of relevant details. The goal is to focus on the most pressing issue first, address that and then move on to the next issue. Focusing on one issue at a time can make the troubleshooting process easier and more efficient.

Planning ahead

Lack of proper planning is of the biggest reasons that a VDI deployment fails. Only with careful preparation can an organization meet its desktop goals. Here are five steps IT can take when planning a VDI deployment.

  1. Identify desktop requirements.

An IT team planning to implement VDI needs a clear vision of what it is trying to achieve, based on user and business requirements. The team should understand what users and applications need to maintain productivity, considering desktop performance, system availability and future scalability. Planners should also consider the different types of users, their operating system needs and any special requirements specific to the implementation.

  1. Plan the infrastructure and its configuration.

After defining requirements, IT can determine what it will take to put together the infrastructure necessary to support them, while factoring in how the infrastructure will integrate into the data center. The goal is to provide enough resources to support the virtual desktops without overprovisioning resources, yet still be able to accommodate projected growth. At the same time, planners must ensure the infrastructure includes the necessary redundancy and storage capabilities to maintain operations. They must also determine whether to build the infrastructure from scratch, implement an appliance such as a hyperconverged infrastructure or go with cloud-hosted virtual desktops.

  1. Build security and compliance into the infrastructure.

IT must plan for security and compliance from the project's inception, considering them at every phase of the planning process. This can include basic security measures such as firewalls, two-factor authentication, antivirus software or third-party malware detection tools. IT should also consider desktop security, such as disabling copy-and-paste functions or access to local USB drives. In addition, planners should consider application security, such as whether they should implement a blocklist or allowlist.

  1. Prioritize the user experience.

Although the user experience is not the only consideration when planning a VDI deployment, it should be at the top of the list. Employees moving from a physical desktop to a virtual environment require adequate notice and training.

Planners should also be prepared for users interacting with their desktops in multiple ways. They might require different applications or operating systems, use multiple client devices or access their desktops from a variety of locations. If their experience is a noticeable step down from their physical desktops, the project could be in serious trouble. No matter what the use case, the goal should be to make the experience better, not worse.

  1. Develop a rollout plan.

Rolling out a VDI deployment should be planned as carefully as the infrastructure itself. IT should not try to roll out every feature across the entire enterprise at once. They should start with what's most important and go from there. A rollout should be made up of carefully planned stages, starting with testing and pilot phases. IT must also ensure that they have the necessary personnel to carry out the VDI deployment through all its stages.

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