Hitachi Compute Blade 500 Series Function Manual page 22

Adaptive Load Balancing
The ALB function makes one team with using two LAN devices and applies one IP
address to the team for ensuring the network data transfer bandwidth. The ALB
function includes the AFT function for ensuring the redundancy.
When the ALB function is active, the LAN driver periodically analyzes the transmission
data traffic, and distributes the traffic load to the LAN devices. One LAN device
functioning as the Primary LAN device transmits and receives data. The remaining
LAN device concurrently transmits the distributed transmission data. If the Primary
LAN device fails, the ALB function carries over the processing to the remaining LAN
device similarly to AFT.
Probing packet is enabled by default for the use of the ALB function(same as
AFT). If it is impossible to normally transmit or receive Probing packet in heavy
traffic network, it might repeat to failover and failback between Primary LAN
device and Secondary LAN device. In such a case, disable the probing packet.
See "How to Disable Monitoring Packet (AFT/ALB)".
When using the ALB function, connect the two LAN devices to the same switching
HUB.
When the ALB function is used, LAN device priorities (Primary and Secondary)
are not defined by default. See How to set LAN device priorities, for details.
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Hitachi Compute Blade 500 Series LAN Advanced Function Manual (for Intel)
One team of up to two LAN
devices
Processing is inherited if the
Primary LAN device fails.
Reception data is distributed to one device
(Primary LAN device) and transmission data
is distributed to two devices.
Switching HUB
LAN Advanced Functions