Specifications

HP Virtual Connect for Cisco Network Administrators (version 1.2x) page 32
Comparing VC and VMware Networking Technology
One method of understanding how Virtual Connect operates on the LAN is to compare the Virtual
Connect networking components and their functionality to the networking components of a
VMware ESX server. Since the networking technology used in a VMware ESX server is commonly
understood and accepted by many customers, understanding the many similarities between VC
and a VMware ESX server will help an implementer have a better understanding of how Virtual
Connect looks to, and behaves on, the external network. Just to be clear, Virtual Connect and a
VMware ESX server are fundamentally different products and address completely different needs
within the datacenter. This comparison is strictly about understanding the similarities between the
two products in regards to networking technology in order to better understand Virtual Connect.
A Description of the VMware Components:
Referencing the figure below, the VMware ESX server (left) is a single physical server running server
virtualization software (VMware) that allows the physical server to host one or more instances of a
virtual server, called a Virtual Machine (VM). In addition, the VMware ESX server provides external
network connectivity to the internal servers (VMs) using a virtual (software) implementation of a layer
2 bridge, called a vSwitch. The VM virtual NICs (vNics) are assigned to one of the vSwitches and the
vSwitches are then associated with real physical NICs residing in I/O slots on the VMware ESX server.
The vSwitches can have one or more physical NICs (uplinks) assigned to them to provide external
network connectivity. If more than one physical NIC is assigned to the same vSwitch, network
redundancy and/or load balancing is provided for the internal servers (VMs) assigned to that
vSwitch. The physical NICs then present one or more MAC addresses to the external network,
depending on the number of VMs communicating to the external network through each physical
NIC.
A Comparative Description of the VC Components:
Referencing the figure below, the c-Class enclosure (right) is a single physical enclosure that hosts
one or more real physical servers, called a blade server. In addition, the c-Class enclosure provides
external network connectivity to the internal servers (blade servers) using a hardware
implementation of a layer 2 bridge, called a Virtual Connect Ethernet network (vNet). The blade
server physical NICs (pNics) are assigned to one of the vNets and the vNets are then associated with
real physical VC uplink ports from VC-Enet modules residing in the I/O bays on the c-Class enclosure.
The vNets can have one or more VC uplinks assigned to them to provide external network
connectivity. If more than one VC uplink is assigned to the same vNet, network redundancy and/or
load balancing is provided for the internal servers (blade servers) assigned to that vNet. The VC
uplinks then present one or more MAC addresses to the external network, depending on the
number of blade servers communicating to the external network through each VC uplink.