Mastering VMware vSphere 6. Marshall Nick

actually back up VMs with VADP. You’ll need a VADP-enabled backup application. There are a growing number of third-party backup applications that are designed to work with VADP, and VMware also offers its own backup tool, VMware Data Protection (VDP). VDP leverages VADP and technology based on EMC Avamar to provide a full backup solution for smaller VMware vSphere environments.

      Using VMware Data Recovery?

      In vSphere 5.1, VMware phased out its earlier data protection tool, VMware Data Recovery (VDR), in favor of VMware Data Protection. Although VDR was provided with vSphere 5.0, VDR is not supported with vSphere 5.1 and later, and you should use VDP instead.

      Virtual SAN (VSAN)

      VSAN is a major new feature included with, but licensed separately from, vSphere 5.5 and later. It is the evolution of work that VMware has been doing for a few years now, building on top of the work of the vSphere Storage Appliance (VSA). VSAN lets organizations leverage the internal storage found in individual compute nodes and turn it into – well, a virtual SAN.

      VSAN requires at least three ESXi hosts (or nodes) but will scale to as many as 64. VSAN also requires solid-state storage in each of the compute nodes providing VSAN storage; this is done to help improve I/O performance given that most compute nodes have a limited number of physical drive spindles present. (Note that the solid-state storage in the servers used by VSAN is separate from solid-state storage that would be used by vSphere’s vSphere Flash Read Cache caching functionality. See the section vSphere Flash Read Cache later in this chapter for more details on using solid-state storage for caching.) VSAN pools the storage across the compute nodes, allowing you to create a datastore that spans multiple compute nodes. VSAN employs algorithms to help protect against data loss, such as ensuring that the data exists on multiple participating VSAN nodes at the same time.

      More information on VSAN is found in Chapter 6, “Creating and Configuring Storage Devices.”

      vSphere Replication vSphere Replication brings data replication, a feature typically found in hardware storage platforms, into vSphere itself. It’s been around since vSphere 5.0, when it was only enabled for use in conjunction with VMware Site Recovery Manager (SRM) 5.0. In vSphere 5.1, vSphere Replication was decoupled from SRM and enabled for independent use without VMware SRM.

      vSphere Replication enables customers to replicate VMs from one vSphere environment to another vSphere environment. Typically, this means from one data center (often referred to as the primary or production data center) to another datacenter (typically the secondary, backup, or disaster recovery [DR] site). Unlike hardware-based solutions, vSphere Replication operates on a per-VM basis, so it gives customers very granular control over which workloads will be replicated and which workloads won’t be replicated.

      You can find more information about vSphere Replication in Chapter 7.

      vSphere Flash Read Cache

      Since the release of vSphere 5.0 in 2011, the industry has seen tremendous uptake in the use of solid-state storage (also referred to as flash storage) across a wide variety of use cases. Because solid-state storage can provide massive numbers of I/O operations per second (IOPS) it can handle the increasing I/O demands of virtual workloads. However, solid-state storage is typically more expensive on a per-gigabyte basis than traditional, hard-disk-based storage and therefore is often deployed as a caching mechanism to help speed up frequently accessed data.

      Unfortunately, without support in vSphere for managing solid-state storage as a caching mechanism, vSphere architects and administrators have had difficulty fully leveraging solid-state storage in their environments. With the release of vSphere 5.5, VMware addresses that limitation through a feature called vSphere Flash Read Cache.

      vSphere Flash Read Cache brings full support for using solid-state storage as a caching mechanism to vSphere. Using this feature, you can assign solid-state caching space to VMs in much the same way as you assign CPU cores, RAM, or network connectivity to VMs. vSphere manages how the solid-state caching capacity is allocated and assigned as well as how it is used by the VMs.

      Hardware vendors that provide solid-state storage devices have partnered with VMware to make their products fully support vSphere Flash Read Cache.

      VMware vSphere Compared to Hyper-V and XenServer

      It’s not possible to compare some virtualization solutions to others because they are fundamentally different in approach and purpose. Such is the case with VMware ESXi and some of the other virtualization solutions on the market.

      To make accurate comparisons between vSphere and others, you must include only Type 1 (“bare-metal”) virtualization solutions. This would include ESXi, of course, Microsoft Hyper-V and Citrix XenServer. It would not include products such as VMware Server and Microsoft Virtual Server, both of which are Type 2 (“hosted”) virtualization products. Even within the Type 1 hypervisors, there are architectural differences that make direct comparisons difficult.

      For example, both Microsoft Hyper-V and Citrix XenServer route all the VM I/O through the “parent partition” or “dom0.” This typically provides greater hardware compatibility with a wider range of products. In the case of Hyper-V, for example, as soon as Windows Server 2012 – the general-purpose operating system running in the parent partition – supports a particular type of hardware, Hyper-V supports it also. Hyper-V “piggybacks” on Windows’ hardware drivers and the I/O stack. The same can be said for XenServer, although its “dom0” runs Linux and not Windows.

      VMware ESXi, on the other hand, handles I/O within the hypervisor itself. This typically provides greater throughput and lower overhead at the expense of slightly more limited hardware compatibility. To add more hardware support or updated drivers, the hypervisor must be updated because the I/O stack and device drivers are in the hypervisor.

      This architectural difference is fundamental, and nowhere is it more greatly demonstrated than in ESXi, which has a small footprint yet provides a full-featured virtualization solution. Both Citrix XenServer and Microsoft Hyper-V require a full installation of a general-purpose operating system (Windows Server 2012 for Hyper-V, Linux for XenServer) in the parent partition/dom0 in order to operate.

      In the end, each of the virtualization products has its own set of advantages and disadvantages, and large organizations may end up using multiple products. For example, VMware vSphere might be best suited in the large corporate datacenter, whereas Microsoft Hyper-V or Citrix XenServer might be acceptable for test, development, or branch office deployment. Organizations that don’t require VMware vSphere’s advanced features like vSphere DRS, vSphere FT, or Storage vMotion may also find that Microsoft Hyper-V or Citrix XenServer is a better fit for their needs.

      As you can see, VMware vSphere offers some pretty powerful features that will change the way you view the resources in your datacenter. vSphere also has a wide range of features and functionality. Some of these features, though, might not be applicable to all organizations, which is why VMware has crafted a flexible licensing scheme for organizations of all sizes.

      Licensing VMware vSphere

      Beginning with VMware vSphere 4, VMware made available new licensing tiers and bundles intended to provide a good fit for every market segment. That arrangement continued with vSphere 5.0. However, with vSphere 5.1 (and continuing with vSphere 6.0), VMware refined this licensing arrangement with the vCloud Suite – a bundling of products including vSphere, vRealize Automation, vCenter Site Recovery Manager, and vRealize Operations Management Suite.

      Although licensing vSphere via the vCloud Suite is likely the preferred way of licensing vSphere moving forward, discussing all the other products included in the vCloud Suite is beyond the scope of this book. Instead, I’ll focus on vSphere and explain how the various features discussed so far fit into vSphere’s licensing model when vSphere is licensed stand-alone.

      Vsphere or Vsphere With Operations Management?

      VMware sells “standalone” vSphere in one of two ways: as vSphere, with all the various kits and editions, and as vSphere with Operations Management. vSphere with Operations Management is the same as vSphere but adds the vRealize Operations