Mastering VMware vSphere 6. Marshall Nick

vSphere Storage DRS, which enables VMware vSphere to dynamically migrate storage resources to meet demand, much in the same way that DRS balances CPU and memory utilization

      vCenter Server plays a central role in any sizable VMware vSphere implementation. In Chapter 3, “Installing and Configuring vCenter Server,” I discuss planning and installing vCenter Server as well as look at ways to ensure its availability. Chapter 3 will also examine the differences between the Windows-based version of vCenter Server and the Linux-based vCenter Server virtual appliance. Because of vCenter Server’s central role in a VMware vSphere deployment, I’ll touch on vCenter Server in almost every chapter throughout the rest of the book. Refer to Table 1.1, earlier in this chapter, for specific cross-references.

      vCenter Server is available in two packages:

      • vCenter Server Essentials is integrated into the vSphere Essentials kits for small office deployment.

      • vCenter Server Standard provides all the functionality of vCenter Server, including provisioning, management, monitoring, and automation.

      You can find more information on licensing and product editions for VMware vSphere in the section “Licensing VMware vSphere.”

      vSphere Update Manager vSphere Update Manager is an add-on package for vCenter Server that helps users keep their ESXi hosts and select VMs patched with the latest updates. vSphere Update Manager provides the following functionality:

      • Scans to identify systems that are not compliant with the latest updates

      • User-defined rules for identifying out-of-date systems

      • Automated installation of patches for ESXi hosts

      • Full integration with other vSphere features like Distributed Resource Scheduler

      vSphere Update Manager works with the Windows-based installation of vCenter Server as well as the prepackaged vCenter Server virtual appliance. Refer to Table 1.1 for more information on where vSphere Update Manager is described in this book.

      VMware vSphere Web Client and vSphere Desktop Client vCenter Server provides a centralized management framework for VMware ESXi hosts, but it’s the vSphere Web Client (and its predecessor, the Windows-based vSphere Desktop Client) where you will spend most of your time.

      With the release of vSphere 5, VMware shifted its primary administrative interface to a web-based vSphere Client. The vSphere Web Client provides a dynamic, web-based user interface for managing a virtual infrastructure and enables you to manage your infrastructure without needing to install the Windows-based vSphere Desktop Client on a system. In its initial release, the vSphere Web Client provided a subset of the functionality available to the “full” Windows-based vSphere Desktop Client. However, in subsequent releases – including the 6.0 release – the vSphere Web Client has been enhanced and expanded to include almost all the functionality you need to manage a vSphere environment. Further, VMware has stated that the vSphere Web Client will eventually replace the Windows-based vSphere Desktop Client entirely. For this reason, I’ll use screen shots of the vSphere Web Client throughout this book unless it is impossible to do so.

      The Windows-based vSphere Desktop Client is still available to allow you to manage individual ESXi hosts, either directly or through an instance of vCenter Server. You can install the vSphere Desktop Client by browsing to the URL of an ESXi host or vCenter Server and selecting the appropriate installation link (although keep in mind that Internet access might be required in order to download the client in some instances). The vSphere Desktop Client provides a rich graphical user interface (GUI) for all day-to-day management tasks and for the advanced configuration of a virtual infrastructure. Although you can connect the vSphere Desktop Client either directly to an ESXi host or to an instance of vCenter Server, the full set of management capabilities are available only when you are connecting the vSphere Desktop Client to vCenter Server.

      As I mentioned earlier, the vSphere Web Client is the stated future direction for VMware vSphere’s management interface. For that reason, I focus primarily on how to use the vSphere Web Client throughout this book. Tasks in the vSphere Desktop Client should be similar, but note that some tasks can be performed only in the vSphere Web Client, not the Windows-based vSphere Desktop Client.

      VMware vRealize Orchestrator

      VMware vRealize Orchestrator (previously named VMware vCenter Orchestrator) is a workflow automation engine that is automatically installed with every instance of vCenter Server. Using vRealize Orchestrator, you can build automated workflows for a wide variety of tasks available within vCenter Server. The automated workflows you build using vRealize Orchestrator range from simple to complex. VMware also makes vRealize Orchestrator plug-ins to extend the functionality to include manipulating Microsoft Active Directory, Cisco’s Unified Computing System (UCS), and VMware vRealize Automation. This makes vRealize Orchestrator a powerful tool to use in building automated workflows in the virtualized datacenter.

      Now that we’ve discussed the specific products in the VMware vSphere product suite, I’d like to take a closer look at some of the significant features.

      Examining the Features in VMware vSphere

      In the following sections, we’ll take a closer look at some of the features that are available in the vSphere product suite. We’ll start with Virtual SMP.

      vSphere Virtual Symmetric Multi-Processing

The vSphere Virtual Symmetric Multi-Processing (vSMP or Virtual SMP) product allows you to construct VMs with multiple virtual processor cores and/or sockets. vSphere Virtual SMP is not the licensing product that allows ESXi to be installed on servers with multiple processors; it is the technology that allows the use of multiple processors inside a VM. Figure 1.2 identifies the differences between multiple processors in the ESXi host system and multiple virtual processors.

Figure 1.2 vSphere Virtual SMP allows VMs to be created with more than one virtual CPU.

      With vSphere Virtual SMP, applications that require and can actually use multiple CPUs can be run in VMs configured with multiple virtual CPUs. This allows organizations to virtualize even more applications without negatively impacting performance or being unable to meet service-level agreements (SLAs).

      In vSphere 5, VMware expanded this functionality by also allowing users to specify multiple virtual cores per virtual CPU. Using this feature, a user could provision a dual “socket” VM with two cores per “socket” for a total of four virtual cores. This approach gives users tremendous flexibility in carving up CPU processing power among the VMs.

      vSphere vMotion and vSphere Storage vMotion

      If you have read anything about VMware, you have most likely read about the extremely useful feature called vMotion. vSphere vMotion, also known as live migration, is a feature of ESXi and vCenter Server that allows you to move a running VM from one physical host to another physical host without having to power off the VM. This migration between two physical hosts occurs with no downtime and with no loss of network connectivity to the VM. The ability to manually move a running VM between physical hosts on an as-needed basis is a powerful feature that has a number of use cases in today’s datacenters.

      Suppose a physical machine has experienced a nonfatal hardware failure and needs to be repaired. You can easily initiate a series of vMotion operations to remove all VMs from an ESXi host that is to undergo scheduled maintenance. After the maintenance is complete and the server is brought back online, you can use vMotion to return the VMs to the original server.

      Alternately, consider a situation in which you are migrating from one set of physical servers to a new set of physical servers. Assuming that the details have been addressed – and I’ll discuss the details of vMotion in Chapter 12, “Balancing Resource Utilization” – you can use vMotion to move the VMs from the old servers to the newer servers, making quick work of a server migration