Qlogic QConvergeConsole CLI 8100 Series, User Manual

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6–Configuring NIC Functionality in the Converged Network Adapter
Configuring the NIC in a Linux Environment
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VLAN Configuration
A virtual LAN (VLAN) is a logical grouping of network hosts connected to a switch
to achieve a logical segmentation of a physical network. By default, all switches
make up a broadcast domain in the layer-2 switched network. Creating a VLAN
breaks up a broadcast domain into smaller domains within a switch by assigning
different ports to different subnets. The benefits of using VLANs include broadcast
control, security, flexibility, and scalability.
VLAN configuration assigns a VLAN ID to a NIC interface. The protocol most
commonly used to configure VLANs is
Virtual LANs IEEE 802.1Q . Using this
protocol, the QLogic adapter NIC function assigns a VLAN ID to each frame that it
transmits. The connected switch interprets the tag, and packets are switched only
within the VLAN. Communication across VLANs requires a layer-3 router.
VLAN Prerequisites
The following software components are required to configure VLANs on Linux
systems with network interface bonding.
 VLAN 802.1q kernel module (8021q)—Linux kernel module that provides
the VLAN 802.1q support for network interfaces. The Linux 8021q VLAN
driver creates VLANs on Linux network interfaces over both physical and
bonded interfaces. The VLAN 802.1q driver is a kernel-loadable module
(8021q.ko) that resides in the
/lib/modules/2.6.18-164.el5/kernel/net/8021q/
directory on
RHEL 5-based distributions.
 vconfig utility—A user-level control program for managing VLANs in Linux.
vconfig is a VLAN (802.1q) configuration program that creates and removes
VLAN devices on a VLAN-enabled kernel (such asRHEL 5). VLAN devices
are virtual Ethernet devices that represent the VLANs on the physical LAN.
For information about the vconfig command, enter the
man vconfig
command to display the manual page.
The VLAN 802.1q kernel module and the vconfig utility are available by default in
all RHEL 5 installations.
NOTE:
The VLAN ID is set for the entire team and not for individual ports in the
team.
NOTE:
To enable all VLAN capabilities in Linux, you must configure VLANs on the
attached Ethernet switch. For information about configuring VLANs on the
switch, refer to the Ethernet switch vendor documentation.