Ethernet I/O Module User's Guide

4 Broadcom Gigabit Ethernet Teaming Services 135

• Configuration Recommendations

Static trunking supports connecting the teamed ports to switches if they are on the same broadcast

domain and support generic trunking. It does not support connecting to a router or Layer 3

switches since the ports must be on the same subnet.

Dynamic Trunking (IEEE 802.3ad Link Aggregation)

This mode supports link aggregation through static and dynamic configuration via the Link

Aggregation Control Protocol (LACP). With this mode, all adapters in the team are configured to

receive packets for the same MAC address. The MAC address of the first adapter in the team is used

and cannot be substituted for a different MAC address. The BASP driver determines the load-

balancing scheme for outbound packets, using Layer 4 protocols previously discussed, whereas the

team's link partner determines the load-balancing scheme for inbound packets. Because the load

balancing is implemented on Layer 2, all higher protocols such as IP, IPX, and NetBEUI are

supported. The attached switch must support the 802.3ad Link Aggregation standard for this mode of

operation. The switch manages the inbound traffic to the adapter while the BASP manages the

outbound traffic. Both the BASP and the switch continually monitor their ports for link loss. In the

event of link loss on any port, traffic is automatically diverted to other ports in the team.

• Network Communications

The following are the key attributes of Dynamic Trunking:

- Failover mechanism - Link loss detection

- Load Balancing Algorithm - Outbound traffic is balanced through a Broadcom proprietary

mechanism based on L4 flows. Inbound traffic is balanced according to a switch specific

mechanism.

- Outbound Load Balancing using MAC Address - No

- Outbound Load Balancing using IP Address - Yes

- Multivendor Teaming - Supported (must include at least one Broadcom Ethernet adapter as a

team member)

• Applications

Dynamic trunking works with switches that support IEEE 802.3ad Link Aggregation dynamic

mode using LACP. Inbound load balancing is switch dependent. In general, the switch traffic is

load balanced based on L2 addresses. In this case, all network protocols such as IP, IPX, and

NetBEUI are load balanced. Therefore, this is the recommended teaming mode when the switch

supports LACP, except when switch fault tolerance is required. SLB is the only teaming mode that

supports switch fault tolerance.

• Configuration Recommendations

Dynamic trunking supports connecting the teamed ports to switches as long as they are on the

same broadcast domain and supports IEEE 802.3ad LACP trunking. It does not support connecting

to a router or Layer 3 switches since the ports must be on the same subnet.