D-Link DGS-3312SR [94/290] Stp port settings

DGS-3312SR Stackable Gigabit Layer 3 Switch

Max Age

The Max Age may be set to ensure that old information does not endlessly circulate

through redundant paths in the network, preventing the effective propagation of the

new information. Set by the Root Bridge, this value will aid in determining that the

Switch has spanning tree configuration values consistent with other devices on the

bridged LAN. If the value ages out and a BPDU has still not been received from the

Root Bridge, the Switch will start sending its own BPDU to all other switches for

permission to become the Root Bridge. If it turns out that your switch has the lowest

Bridge Identifier, it will become the Root Bridge. The user may choose a time

between 6 and 40 seconds. The default value is 20.

Forward Delay

The Forward Delay can be from 4 to 30 seconds. Any port on the Switch spends

this time in the listening state while moving from the blocking state to the forwarding

state.

Last Topology Change

This field shows the time, in seconds, since the last spanning tree topology change.

Topology Changes

Count

This field displays the number of times that the spanning tree topology has changed

since the original initial boot up of the Switch.

STP Port Settings

STP can be set up on a port per port basis. To view the following window click Configuration > Spanning Tree > STP

Port Settings:

Figure 4- 44. STP Port Settings and Table window

In addition to setting Spanning Tree parameters for use on the Switch level, the Switch allows for the configuration of

port cost, to be

groups of ports, each port-group of which will have its own spanning tree, and will require some of its own configuration

settings. An STP Group will use the Switch-level parameters entered above, with the addition of Port Priority and Port

Cost.

An STP Group spanning tree works in the same way as the Switch-level spanning tree, but the root bridge concept is

replaced with a root port concept. A root port is a port of the group that is elected based on port priority and