Information Technology Reference
In-Depth Information
These seven tabs make up the major areas of coni guration for VUM, so let's take a closer
look at each section:
Baselines And Groups
Baselines are a key part of how VUM works. To keep ESX/ESXi hosts
and VMs updated, VUM uses
baselines
.
VUM uses several different types of baselines. First, baselines are divided into host baselines,
designed to update ESX/ESXi hosts, and VM/VA baselines, which are designed to update
VMs and virtual appliances.
Importance of Baselines
As vSphere becomes more central to an organization's infrastructure, baselines become increas-
ingly important. Host baselines provide a stable platform for ever intertwined components. Many
datacenter tools take advantage of vSphere APIs, such as the storage arrays via vSphere APIs for
Array Integration (VAAI) and backup tools via vSphere APIs for Data Protection (VADP), and
interact with vCenter and the hosts in a nontrivial way. Keeping all hosts at the same build level is
crucial to maintaining a reliable environment. Additionally, keeping your VMs at a standardized
hardware level with the same VMware Tools guest drivers minimizes the variances that can create
support issues and troubleshooting headaches.
Baselines are further subdivided into patch baselines, upgrade baselines, and host extension
baselines. Patch baselines dei ne lists of patches to be applied to an ESX/ESXi host; upgrade
baselines dei ne how to upgrade an ESX/ESXi host, the VM's hardware, VMware Tools, or a
virtual appliance. There's also another type of baseline for hosts, known as host extension
baselines; these are used to manage the extensions installed onto your ESX/ESXi hosts.
Finally, patch baselines are divided again into dynamic baselines and i xed baselines.
Dynamic baselines can change over time—for example, all security host patches since a cer-
tain date. But i xed baselines remain constant—for example, a specii c host patch that you
want to ensure is applied to your hosts.
When Should You Use Fixed Baselines or Dynamic Baselines?
Fixed baselines are best used to apply a specifi c fi x to a group of hosts. For example, let's say that
VMware released a specifi c fi x for ESX/ESXi and you wanted to be sure that it was installed on all
your hosts. By creating a fi xed baseline that included just that patch and attaching that baseline
to your hosts, you could ensure that your hosts had that specifi c fi x installed. Another use for
fi xed baselines is to establish the approved set of patches that you have tested and are now ready
to deploy to the environment as a whole.
Dynamic baselines, on the other hand, are best used to keep systems current with the latest sets
of patches. Because these baselines evolve over time, attaching them to your hosts can help you
understand just how current your systems are (or aren't!).
