SMC Networks 8124PL2, Management Manual

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Spanning Tree Algorithm Configuration
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Web – Click Address Table, Address Aging. Specify the new aging time, click Apply .
Figure 3-68. Setting the Aging Time
CLI – This example sets the aging time to 300 seconds.
Spanning Tree Algorithm Configuration
The Spanning Tree Algorithm (STA) can be used to detect and disable network
loops, and to provide backup links between switches, bridges or routers. This allows
the switch to interact with other bridging devices (that is, an STA-compliant switch,
bridge or router) in your network to ensure that only one route exists between any
two stations on the network, and provide backup links which automatically take over
when a primary link goes down.
The spanning tree algorithms supported by this switch include these versions:
• STP – Spanning Tree Protocol (IEEE 802.1D)
• RSTP – Rapid Spanning Tree Protocol (IEEE 802.1w)
STA uses a distributed algorithm to select a bridging device (STA-compliant switch,
bridge or router) that serves as the root of the spanning tree network. It selects a
root port on each bridging device (except for the root device) which incurs the lowest
path cost when forwarding a packet from that device to the root device. It selects a
designated bridging device from each LAN which incurs the lowest path cost when
forwarding a packet from that LAN to the root device.
It then selects a port on the designated bridging device to communicate with each
attached LAN or host device as a designated port. After determining the lowest cost
spanning tree, it enables all root ports and designated ports, and disables all other
ports. Network packets are therefore only forwarded between root ports and
designated ports, eliminating any possible network loops.
Console(config)#mac-address-table aging-time 300 4-138
Console(config)#