A VMware vCloud is made up of one or more vCloud Director servers that are integrated with underlying vSphere components. The vCloud is a new abstraction layer above vCenter Server consuming the resources that vCenter manages; this allows a user to self-provision virtual environments utilizing memory, compute, storage, and networking resources. Cloud computing has become a vague, arbitrary phrase, but there are six characteris- tics that define exactly what a cloud should consist of

• self-service
• elasticity
• pay as you go
• multi-tenancy
• resource pooling
• ubiquitous access

A private cloud is an infrastructure whose resources are only used internally. A public cloud is an infrastructure made available to external customers for a price. A hybrid cloud combines two or more clouds with some kind of standardized technology, like VMware vCloud Connector, while each cloud maintains its own unique identity.

The foundation of the vCloud centers on the networking configuration. Networking occurs over three different layers: external, organization, and vApp; it is imperative to properly configure and manage these networks so that the vCloud can be consumed. Think of vCloud networking as an onion that will be peeled back to reveal each layer, starting with the organization’s networks that are created by an administrator with the system administrator role in vCloud Director. A system administrator is the highest role within the vCloud.

For further reading, check out my vCloud Director 5.1 Networking Concepts white paper!

The first object that is created within vCloud Director is the External Network. An External Network provides the connection from the cloud to the outside world, allowing inter-Cloud connections and is port group based. Even though this connection is called the external connection, an Internet connection is not actually required; this can be set up to provide a connection to several different internal entities, like ESXi hosts, without an actual route to the Internet. Since this connection is port group-based, then the port group needs to exist prior to attempting to establish the connection. The port group can be defined on a standard vSwitch, a distributed vSwitch, or on a Nexus 1000V. Organization virtual datacenters can use the external networks to provide Internet connectivity to the organizations and the virtual machines that reside within a vApp, given that the vApp network is configured for that. By creating an external network, vCloud Director is effectively configured to send all external traffic using the port group(s) selected. Should there be multiple external networks created then be sure to separate them by using VLANs. Only someone with the system administrator role within the vCloud can create and manage external networks.

For further reading, check out my vCloud Director 5.1 Networking Concepts white paper!