Basic System Administration : Managing the VI Client Inventory : Understanding VI Client Objects

Understanding VI Client Objects
There are several ways to get insight into the relationships between different objects:
Viewing through the Maps feature – shows the inventory object relationships in graphical form.
Clicking an object in the inventory – provides a list of tabbed content that lists related objects.
For example, a datastore has a virtual machine tab that lists the virtual machines that use the datastore. There is also a host tab that list the hosts that can access the datastore.
Viewing Inventory > Hosts and Clusters – provides a view of the set of virtual machines that run on a particular host, cluster, or resource pool. Each object has a tab that displays all the virtual machines associated or contained within in.
However, the Hosts and Clusters view is not a complete list of available virtual machines and templates. Only the Inventory > Virtual Machines and Templates option displays all the virtual machine and templates. Through this view you can organize virtual machines into arbitrary folder hierarchies.
The Virtual Infrastructure Client is used to connect directly to an ESX Server or indirectly to an ESX Server through a VirtualCenter Server. The VI Client displays only those functions that are appropriate to the type of server connected to it. For example, if the VI Client is connected to an ESX Server, the clusters functionality is not displayed.
The figure below lists the objects of a VMware Infrastructure environment. The objects are in hierarchical order. Templates, networks, and datacenters are displayed on their own inventory panel. All other objects appear in the Hosts & Clusters inventory panel. All four panels are linked to the root folder.
Figure 6-1. Virtual Infrastructure Client Hierarchy
When the VI Client is connected to an ESX Server, the root is the host itself. Contained objects include the host root resource pool, child resource pools, and virtual machines. Clusters, folders, datacenters, networks, and datastores do not appear in the inventory when the VI Client is connected only to an ESX Server.
Some objects serve only as organizational structures. These provide a means for you to organize your objects by department, group, company function, location, and so on.
Other objects limit a group of contained objects. For example, a VMotion failover can occur only within a cluster, not between clusters. Similarly a VMotion failover can occur only within a datacenter, not between datacenters.
The Virtual Infrastructure Client objects are as follows:
Root folder – In VirtualCenter Server only. Child objects are datacenters or subfolders. The root folder is set as a default for every VirtualCenter Server. You can change the name, but not add or remove it.
Folders – In VirtualCenter Server only. Child objects are datacenters, hosts, clusters, virtual machines, or subfolders.
Datacenters – In VirtualCenter Server only. Child objects are folders, clusters, or hosts.
A datacenter contains clusters, hosts, and virtual machines. All actions taken upon managed hosts and virtual machines are applied within their datacenter. Within a datacenter, you can monitor and manage virtual machines separately from their hosts and use VMotion. You cannot perform migration between datacenters.
Clusters – In VirtualCenter Server only. Child objects are hosts, virtual machines, or resource pools.
If your system is licensed, you can enable the following cluster features:
VMware HA – Allows VirtualCenter to migrate and restart a virtual machine when a host fails. VMware HA is not listed as an inventory object itself, but it allows the cluster object to be seen.
VMware DRS – Monitors the VirtualCenter environment, makes initial placement recommendations, makes virtual machine migration recommendations, and enables VirtualCenter to automatically place and migrate virtual machines on hosts to attain the best use of cluster resources. VMware DRS is not listed as an inventory object itself, but it allows the cluster object to be seen.
Refer to the Resource Management Guide for comprehensive information on using Virtual Infrastructure Client clusters.
Hosts – Child objects are virtual machines or resource pools. Hosts are ESX Server systems. The term host refers to the virtualization platform that is the host to the virtual machines. Host is the default top structure for a standalone ESX Server.
When the VirtualCenter Server is connected to the Virtual Infrastructure Client, all ESX Server systems registered with VirtualCenter are simply referred to as hosts. ESX Server systems directly connected to the Virtual Infrastructure Client are referred to as standalone hosts.
Refer to the Server Configuration Guide for comprehensive information on configuring your ESX Server.
Resource pools – Child objects are virtual machines or resource pools. They are available on ESX Server hosts as well as through VirtualCenter Servers.
A Virtual Infrastructure Client resource pool is used to allocate host-provided CPU and memory to the virtual machines resident to the host.
Refer to the Resource Management Guide for comprehensive information on using Virtual Infrastructure Client resource pools.
Virtual machines – Located within a host, virtual disks on a datastore, associated within a cluster or resource pool. Can be listed as a child object to hosts, clusters, or resource pools. Can be moved between hosts or clusters. When adding to a cluster or resource pool, you must specify or have in the cluster or resource pool a designated target host.
Networks – In VirtualCenter Server only. Child object to datacenters. Networks are discovered when hosts are added to the VMware Infrastructure environment.
Refer to the Server Configuration Guide for comprehensive information on configuring your ESX Server.
Datastores – In VirtualCenter Server only. Child object to datacenters. Datastores are discovered when hosts are added to the VMware Infrastructure environment. This includes the discovery of datastores that are local to the managed host as well as datastores on the SAN or NAS.
Refer to the Server Configuration Guide for comprehensive information on configuring your ESX Server.