Datasheet

Emulex VFA5 ML2 Dual Port 10GbE SFP+ Adapter for IBM System x 8
Modes of operation
The Emulex VFA5 ML2 Dual Port 10GbE SFP+ Adapter supports two types of virtual NIC (vNIC)
operating modes, and a physical NIC (pNIC) operating mode:
IBM Virtual Fabric Mode (also known as vNIC1 mode) works only with an IBM RackSwitch™ G8124E
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and G8264. In this mode, the Emulex adapter communicates with the IBM switch to obtain vNIC
parameters (using DCBX). A special tag is added within each data packet and is later removed by the
NIC or switch for each vNIC group to maintain separation of the virtual data paths.
In vNIC mode, each physical port is divided into four virtual ports for a maximum of eight virtual NICs
per adapter. The default bandwidth for each vNIC is 2.5 Gbps. Bandwidth for each vNIC can be
configured through the IBM RackSwitch from 100 Mbps to 10 Gbps, up to a total of 10 Gb per
physical port. The vNICs can also be configured to have 0 bandwidth if you must allocate the
available bandwidth to fewer than four vNICs per physical port. In IBM Virtual Fabric Mode, you can
change the bandwidth allocations through the IBM switch user interfaces without requiring a reboot of
the server.
vNIC bandwidth allocation and metering are performed by both the switch and the VFA. In such a
case, a bidirectional virtual channel of an assigned bandwidth is established between them for every
defined vNIC.
In Switch Independent Mode (also known as vNIC2 mode), the adapter works with any 10 Gb
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Ethernet switch. Switch Independent Mode offers the same capabilities as IBM Virtual Fabric Mode in
terms of the number of vNICs and the bandwidth each can be configured to have. Switch Independent
Mode extends the existing customer VLANs to the virtual NIC interfaces. The IEEE 802.1Q VLAN tag
is essential to the separation of the vNIC groups by the NIC adapter or driver and the switch. The
VLAN tags are added to the packet by the applications or drivers at each endpoint rather than by the
switch.
vNIC bandwidth allocation and metering are performed only by VFA itself. In such a case, a
unidirectional virtual channel is established where the bandwidth management is performed only for
the outgoing traffic on a VFA side (server-to-switch). The incoming traffic (switch-to-server) uses the
all available physical port bandwidth, as there is no metering that is performed on either the VFA or a
switch side.
In vNIC2 mode, when storage protocols are enabled on the Emulex 10GbE Virtual Fabric Adapters,
six vNICs (three per physical port) are Ethernet, and two vNICs (one per physical port) are either
iSCSI or FCoE.
In pNIC mode, the adapter operates as a standard dual-port 10 Gbps Ethernet adapter, and it
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functions with any 10 GbE switch. In pNIC mode, with the Emulex FCoE/iSCSI License, the card
operates in a traditional Converged Network Adapter (CNA) mode with two Ethernet ports and two
storage ports (iSCSI or FCoE) available to the operating system.