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With VMware View Composer, administrators can use the linked clones feature to save space compared to using a full virtual machine. The advantages of using this VMware View functions is detailed in chapter 7 of the book VMware Horizon Suite: Building End User Services by authors Paul O'Doherty and Stephane Asselin.
In this chapter (available to download here) the authors cover the creation and management of desktop pools, such as backing up the environment, replacing the certificates and patching. The chapter, titled "View Operations and Management", goes more in-depth with how administrators can control permissions in VMware View. Before creating desktop pools, the authors suggest creating access groups, which can organize and set roles and responsibilities for end users. Instead of being restricted to desktop pools being sorted by location and function, the authors explain how access groups let you separate the pools in more detail.
After the step-by-step instructions on how to create access groups, O'Doherty and Asselin dig deeper into the three different types of desktop pools: automatic, manual and Microsoft RDS. Automatic desktop pools are automatically provisioned and customized by VMware View. Manual desktop pools are created from existed machines and physical desktops.
The authors explain the two possible kinds of relationships between the user and desktop in automatic desktop pools: persistent and floating. Persistent is when the desktop is assigned to a specific user. Floating is when the desktop is assigned to a user, but when the user signs off, that desktop can be assigned to another user.
O'Doherty and Asselin go on to explore the power settings of VMware View, View Composer and entitlement, which is the process of assigning the desktop pools to users. There are many aspects to entitlement, such as replica, which the authors detail below in this excerpt from the chapter.
A replica is a read-only copy of the parent VM and contains a snapshot file of the original configuration. View Composer uses the replica to create the linked clone View desktops. The replica is used to right-size the VM by moving from the parent VM format to a thin provisioned VM. From VMware View 4.5 and on, you can store replicas in separate data stores.
This enables you to store the replica on high-performance disk on the SAN or local SSDs. It is from the replica that the linked clone tree is built. Keep in mind, though, that if you use a local disk, the linked clone tree also resides on the local disk.
The use of local SSDs should be reserved for stateless View desktops in a nonpersistent environment. The point of using a local SSD is to take advantage of the extremely high I/Ocapabilities of the technology.
When you use View Composer, desktops are created from a replica, a linked clone is created for each VM, and a snapshot is taken to create a checkpoint to enable a refresh or rollback operation.