Using VLANs, Spanning Tree, and Hunt Groups (Layer 2 and Layer 3)

 

Table 12-3.Spanning Tree Options

 

 

Parameter

Definition

 

 

IEEE 802.1D

Entire switch is a single IEEE 802.1D-compliant bridge.

 

Note: When the spanning tree mode is set to IEEE 802.D,

 

BPDUs are sent out ports in Clear (non-trunked) format even if

 

the port has a trunking format (3Com, 802.1Q or Dual Layer)

 

defined.

 

 

Per VLAN

Each VLAN functions as a separate IEEE 802.1D-compliant

 

bridge.

 

Note: If you disable spanning tree on a single VLAN, spanning

 

tree will be re-enabled when the switch is reset.

 

In order for spanning tree to function properly with 3Com

 

trunked ports, the spanning tree mode should be set to

 

per-VLAN. In Per VLAN spanning tree, there is one instance of

 

spanning tree for each VLAN and the BPDUs are tagged with the

 

VLAN ID, ensuring they are interpreted correctly on the

 

receiving end.

 

 

Dual Layer

Spanning tree terminates at edge of the switch network.

 

Spanning Tree per VLAN within the switch network.

 

 

Disable

Spanning tree not used.

 

 

4.Click APPLY save your changes, or CANCEL to restore previous settings.

5.In the Bridge column, click on a bridge name to set bridge parameters. The Spanning Tree Bridge Configuration dialog box opens.

6.Use Table 12-4 to select bridge-level parameters:

 

Table 12-4.Bridge-Level Parameters

 

 

Parameter

Definition

 

 

Mode

Determines whether spanning tree is enabled or disabled for

 

this bridge.

 

 

Priority

STP Priority level for this bridge.

 

 

Bridge Max Age

Sets the maximum amount of time that this bridge retains

 

bridging information before discarding. When the

 

maximum age expires, the bridge assumes it has lost

 

connection to the network, and sends out requests to be

 

re-added to the spanning tree.

 

 

Bridge Hello Time

Time between generation of BPDUs by the root bridge.

 

 

12-8

Cajun P550/P220 Switch Operation Guide