What's New in VMware vSphere 4: Virtual Networking

Abstract

VMware vSphere introduces a number of new features and capabilities to virtual networking under VMware® vNetwork. vNetwork is the new name to describe the collection of networking technologies for optimally integrating networking and I/O functionality into vSphere.

VMware vNetwork: Summary of Enhancements

The major enhancements to VMware vNetwork are as follows. These are further explained in the sections below.

• vNetwork Distributed Switch (vDS)-VMware's next generation virtual networking solution for spanning multiple hosts with a single virtual switch representation. vDS enables and includes some additional enhancements as follows:
  • Private VLANs
  • Network VMotion-tracking of VM networking state, improving troubleshooting and enabling
  • 3rd Party Virtual Switch support with the Cisco Nexus 1000V Series Virtual Switch
  • Bi-directional traffic shaping
• VMXNET3-Third generation para-virtualized NIC
• IPv6-support extended to vmkernel and Service Console ports

vNetwork Distributed Switch

The vNetwork Distributed Switch (vDS) extends the features and capabilities and features of virtual networks while simplifying provisioning and the ongoing process of configuration, monitoring, and management.

With ESX 3.5 and prior releases, virtual networks were constructed using virtual switches or vSwitches. Each ESX host would use one or more vSwitches to connect the VMs with the server NICs and the outside physical network.

Simplified Network Provisioning, Configuration and Management with vDS

In addition to continuing support for the vSwitch (now known as the Standard Switch), vSphere introduces an additional choice for VMware virtual networking with the vNetwork Distributed Switch. vDS eases the management burden of per host, virtual switch configuration management by treating the network as an aggregated resource. Individual, host-level virtual switches are abstracted into a single large vNetwork Distributed Switch that spans multiple hosts at the Datacenter level. Port Groups become Distributed Virtual Port Groups (DV Port Groups) that span multiple hosts and ensure configuration consistency for VMs and virtual ports necessary for such functions as VMotion.

Distributed Virtual Port Groups and Distributed Virtual Uplinks

Many of the concepts involved in configuring and managing a Standard Switch are carried forward with the vDS.

Distributed Virtual Port Groups (DV Port Groups) are port groups associated with a vDS and specify port configuration options for each member port. DV Port Groups define how a connection is made through the vDS to the Network. Configuration parameters are similar to those available with Port Groups on Standard Switches. The VLAN ID, traffic shaping parameters, port security, teaming and load balancing configuration, and other settings are configured here.

Distributed Virtual Uplinks (dvUplinks) are a new concept introduced with vDS. dvUplinks provide a level of abstraction for the physical NICs (vmnics) on each host. NIC teaming, load balancing, and failover policies on the vDS and DV Port Groups are applied to the dvUplinks and not the vmnics on individual hosts. Each vmnic on each host is mapped to a dvUplinks, permitting teaming and failover consistency irrespective of vmnic assignments. This is illustrated in the dvUplink box in Figure 3. vmnic0 on each of the three hosts (esx09a, esx10b, esx9b) is mapped to dvUplink1. If desired, any of the vmnics could be assigned on any of the hosts to dvUplink1.

New Features with vDS

In addition to easing the configuration and management burden, vDS brings with it a number of new features and capabilities to address some common and emerging virtual network requirements. Note that these features are not available with Standard Switches.

Private VLANs

Private VLAN (PVLAN) support enables broader compatibility with existing networking environments using Private VLAN technology. Private VLANs enable users to restrict communication between virtual machines on the same VLAN or network segment, significantly reducing the number of subnets needed for certain network configurations.

Figure 4 illustrates how this concept works with a vDS. Private VLANs are configured on a vDS with allocations made to the Promiscuous Private VLAN, the Community Private VLAN and the Isolated Private VLAN. DV Port Groups can then use one of these Private VLANs and VMs are then assigned to a DV Port Group. Within the subnet, VMs on the Promiscuous Private VLAN can communicate with all VMs; VMs on the Community Private PVLAN can communicate amongst themselves and those on the Promiscuous Private VLAN; VMs on the isolated Private VLAN can only communicate with VMs on the Promiscuous Private VLAN.

Note that the adjacent physical switches must support Private VLANs and be configured to support the Private VLANs allocated on the vDS.

Related Courses

VMware vSphere Fast Track Program (VSFT)
VMware vSphere: Install, Configure, Manage (VSICM)