User guide

HP Virtual Connect for Cisco Network Administrators (version 4.x)
Document Number: C01386629 Date: January 2014
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to the various ports – IE ports that are not mapped cannot communicate.
A VC Administrator defines vNets and, optionally, assigns VC uplinks to the vNets to provide
external network connectivity. Once the vNets are defined, they are available for the Server
Administrator to assign to server NIC ports. When a Server Admin moves a server profile from
one server bay to another, the vNet assignments and, if used, managed MAC addresses (see
section entitled “VC Managed MAC Addresses) are moved with the profile. This allows the
server administrator to easily move the “Ethernet connectivity profile” for a server from one bay to
another without requiring the assistance of the Network Administrator.
A vNet can be used to bridge together multiple VC downlinks for an internal-to-the-enclosure-
only network or a vNet can be used to bridge together one or more VC downlinks with one or
more VC uplinks to provide external network connectivity for the blade servers in the
enclosure. A vNet cannot be used to bridge together multiple VC uplinks to provide
connectivity between two external devices or to provide connectivity between two external
networks. Virtual Connect is not, and can not be configured as, a transit device. In other words,
VC can only provide internal connectivity between blade servers and\or VC can provide external
connectivity to blade servers but Virtual Connect cannot provide connectivity between two external
devices.
The basic definition of a Virtual Connect Network, or vNet, is a logical grouping of VC ports
(downlinks or downlinks & uplinks) that comprise a single layer 2 network or broadcast domain.
A vNet is analogous to a vSwitch, as used by VMware technology (see “Comparing VC and
VMware Networking Technology” for an in-depth comparison). A vNet does not always represent
a one-to- one correlation with a VLAN, as can be seen in the next section entitled “Virtual
Connect Ethernet Connectivity Designs”.
Server NIC ports assigned to the same vNet can communicate directly (at layer 2) without having to
leave the enclosure. In the figure below, Server Blade 1 and Server Blade 2 can communicate with
each other within the VC Domain. Also, server NIC ports in different vNets are isolated (at layer 2)
by Virtual Connect from other server NIC ports. Server Blade 16 is isolated from Server Blades 1
thru 3.
Figure 13. Sample VC Domain Showing Various Uses of vNets