Lag Load Sharing - Dell PowerConnect B-RX Configuration Manual

8

LAG load sharing

LAG load sharing
Traffic on BigIron RX switches is load balance over a LAG by using the Hash Based Load Sharing
method. The Hash Based Load Sharing method is based on the packet type and cannot be
changed.
The device shares the traffic load evenly across the ports in a LAG group, while ensuring that
packets in the flow are not reordered. Individual flows are assigned a trunk index to identify them.
Traffic from each flow is then distributed across the ports in the LAG group using a hash index as
follows:
•
•
•
The device uses the hash index in the following formula, using the modulo operator (written as "%"
in C programming language).
(hash index)% (Number of trunk ports in a trunk group) = selected trunk port
240
For L2 traffic, the hash index is based on the following:
•
Layer-2 packets with an IPv4 payload: source IPv4 address, source mac addresses,
destination IPv4 address, desination mac address and TCP/UDP source port and
TCP/UDP destination port.
For L3 traffic, the hash index is based on the following:
•
IPv4 non-TCP/UDP packets: source MAC address and destination MAC address, source IP
address and destination IP address
•
IPv4 TCP packets: source MAC address and destination MAC address, source IP address
and destination IP address, and TCP source port and TCP destination port.
•
IPv4 UDP packets: source MAC address and destination MAC address, source IP address
and destination IP address, and UDP source port and UDP destination port.
•
IPv6 non-TCP/UDP packets: source MAC address and destination MAC address, source IP
address and destination IP address.
•
IPv6 TCP packets: source MAC address and destination MAC address, source IP address
and destination IP address, and TCP source port and TCP destination port.
•
IPv6 UDP packets: source MAC address and destination MAC address, source IP address
and destination IP address, and UDP source port and UDP destination port.
For L2 VPN traffic, the hash index is based on the following:
•
Layer-2, non-IPv4.IPv6 packets: source MAC address and destination MAC address.
•
IPv4, non-TCP/UDP packets: source MAC address and destination MAC address, source IP
address and destination IP address.
•
IPv4 TCP packets: source MAC address and destination MAC address, source IP address
and destination IP address, and TCP source port and TCP destination port.
•
IPv4 UDP packets: source MAC address and destination MAC address, source IP address
and destination IP address, and UDP source port and UDP destination port.
•
IPv6 non-TCP/UDP packets: source MAC address and destination MAC address, source IP
address and destination IP address.
•
IPv6 TCP packets: source MAC address and destination MAC address, source IP address
and destination IP address and TCP source port and TCP destination port.
•
IPv6 UDP packets: source MAC address and destination MAC address, source IP address
and destination IP address, and UDP source port and UDP destination port.
BigIron RX Series Configuration Guide
53-1002253-01