Information Technology Reference
In-Depth Information
Figure 9.15
h e display name
assigned to a VM is
used in a variety of
places.
Sizing Virtual Machine Hard Disks
The answer to the third question—how big to make the hard disks in your VM—is a bit more
complicated. There are many different approaches, but some best practices facilitate the man-
agement, scalability, and backup of VMs. First and foremost, you should create VMs with mul-
tiple virtual disk i les to separate the operating system from the custom user/application data.
Separating the system i les and the user/application data will make it easier to increase the
number of data drives in the future and allow a more practical backup strategy. A system drive
of 25 GB to 30 GB, for example, usually provides ample room for installation and continued
growth of the operating system. The data drives across different VMs will vary in size because
of underlying storage system capacity and functionality, the installed applications, the func-
tion of the system, and the number of users who connect to the computer. However, because
the extra hard drives are not operating system data, it will be easier to adjust those drives when
needed.
Keep in mind that additional virtual hard drives will pick up on the same naming scheme as
the original virtual hard drive. For example, a VM named Server1 that has an original virtual
hard disk i le named win2k12-02.vmdk will name the new virtual hard disk i le win2k12-02_1
.vmdk. For each additional i le, the last number will be incremented, making it easy to identify
all virtual disk i les related to a particular VM. Figure 9.16 shows a VM with two virtual hard
disks so that you can see how vSphere handles the naming for additional virtual hard disks.
In the next chapter, “Using Templates and vApps,” you'll revisit the process of creating
VMs to see how to use templates to implement and maintain an optimal VM coni guration
that separates the system data from the user/application data. At this point, though, now that
you've created a VM, you're ready to install the guest OS into the VM.
