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Each PCIe device can contain multiple PFs. A PF is a PCIe partition which has a complete
configuration space and can be found, managed, and operated like a PCIe device. By using a PF,
you can configure or control the PCIe device and move data in or out of the device. The software
regards a PF as an independent PCIe device so that multiple devices can be integrated in the same
chip.
NPAR divides network adapter ports into multiple PFs which support different features. Each port on
the network adapter can be divided into eight PFs.
SR-IOV
Both ports on the network adapter support SR-IOV.
SR-IOV is a hardware-based virtualization solution used to improve the I/O performance of a VM to a
level comparable to the performance of a physical machine. As an extension of PCIe, SR-IOV
improves performances such as I/O sharing, integration, isolation, migration, and simplified
management, and enhances scalability. SR-IOV also allows users to integrate network hardware
resources and multiple VMs to operate on the integrated hardware.
SR-IOV allows the device to separate accesses to its resources among various PCIe hardware
features. A PF is a PCIe physical partition and a VF is a lightweight PCIe logical partition separated
from a PF. You can assign a VF to an application. A VF shares physical device resources and
executes I/O with no cost of the CPU and VM management program.
The network adapter supports 0 to 96 VFs for each PF.
VLAN (802.1Q VLAN)
Each port on the network adapter supports a maximum of 4094 VLANs.
A network adapter only transmits packets, and does not tag or untag packets. The VLAN ID is in the
range of 1 to 4094 and is assigned by the operating system.
VLAN refers to a group of logical devices and users working at Layer 2 and Layer 3. A VLAN is a
broadcast domain. Communication between VLANs is supported by Layer 3 routers. Compared with
LAN, VLAN has less adding and modification overhead and can control broadcasts to enhance
network security and bring flexibility.
Bonding
The bonding feature binds physical NICs to form a logical NIC in the Linux operating system. It can
be used to improve network throughput and availability and provide network redundancy and load
balancing.
Bonding has the following modes:
•
mode=0, round-robin policy (balance-rr)
—Transmits data packets between backup devices
in sequence. This mode is used commonly.
•
mode=1, active-backup policy (active-backup)
—Only the master device is in active state. A
backup device takes over the services when the master device fails. This mode is used
commonly.
•
mode=2, XOR policy (balance-xor)
—Transmits data packets based on a specified
transmission hash policy.
•
mode=3, broadcast policy
—Transmits data packets out of each interface of a backup device.
This mode is error tolerant.
•
mode=4, IEEE 802.3ad dynamic link aggregation (802.3ad)
—Creates an aggregation group
where group members share the same rated speed and full duplex mode settings. Backup
device selection for traffic output is based on transmission hash policy. In this mode, the switch
must support IEEE 802.3ad and have specific configurations.
•
mode=5, adaptive transmit load balancing (balance-tlb)
—Does not require specific
switches. This mode allocates outgoing traffic to backup devices according to the device loads.
If a backup device that is receiving traffic is faulty, another backup device takes over the MAC
address of the faulty backup device.
