4 Broadcom Gigabit Ethernet Teaming Services
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4.8.5 Port Fast/Edge Port
To reduce the effect of TCNs on the network (for example, increasing flooding on switch ports), end
nodes that are powered on/off often should use the Port Fast or Edge Port setting on the switch port
they are attached to. Port Fast or Edge Port is a command that is applied to specific ports and has the
following effects:
• Ports coming from link down to link up will be put in the forwarding STP mode instead of going
from listening to learning and then to forwarding. STP is still running on these ports.
• The switch does not generate a Topology Change Notice when the port is going up or down.
4.8.6 Layer 3 Routing/Switching
The switch that the teamed ports are connected to must not be a Layer 3 switch or router. The ports in
the team must be in the same network.
4.8.7 Teaming with Hubs (for troubleshooting purposes
only)
SLB teaming can be used with 10/100 hubs, but it is only recommended for troubleshooting
purposes, such as connecting a network analyzer in the event that switch port mirroring is not an
option.
4.8.8 Hub Usage in Teaming Network Configurations
Although the use of hubs in network topologies is functional in some situations, it is important to
consider the throughput ramifications when doing so. Network hubs have a maximum of 100 Mbps
half-duplex link speed, which severely degrades performance in either a Gigabit or 100 Mbps
switched-network configuration. Hub bandwidth is shared among all connected devices; as a result,
when more devices are connected to the hub, the bandwidth available to any single device connected
to the hub is reduced in direct proportion to the number of devices connected to the hub.
It is not recommended to connect team members to hubs; only switches should be used to connect to
teamed ports. An SLB team, however, can be connected directly to a hub for troubleshooting
purposes. Other team types can result in a loss of connectivity if specific failures occur and should
not be used with hubs.
