Business Policy Switch User Guide

Using the Business Policy Switch 2000 Version 1.2

STG configuration guidelines

This section provides important information on configuring STGs:

• An STG must be created in the following order:

— Create the STG

— Add the existing VLAN and port memberships

— Enable the STG

• When you create a VLAN, that VLAN automatically belongs to STG 1, the

default STG. If you want the VLAN in another STG, you must move the

VLAN by assigning it to another STG.

• You move a newly created VLAN to an existing STG by following this order:

— Create the VLAN

— Delete the VLAN from STG1

— Add the VLAN to an existing STG

• You cannot delete or move VLAN1 from STG1.

• VLANs must be contained within a single STG; a VLAN cannot span

multiple STGs. By confining VLANs within a single STG, you avoid

problems with spanning tree blocking ports and causing a loss of connectivity

within the VLAN. When a VLAN spans multiple switches, the VLAN must

be within the same spanning tree group (have the same STG ID) across all the

switches.

• All VLANs in the same shared database (SVL) must be assigned to the same

STG.

• All members of a particular MultiLink Trunking (MLT) group must be

assigned to the same STG; that is, they can belong to one and only one STG.

• A port that is not a member of any VLAN cannot be added to any STG. The

port must be added to a VLAN, and that VLAN added to the desired STG.

• Tagged ports can belong to more than one STG, but untagged ports can

belong to only one STG.

• When a tagged port belongs to more than one STG, the egress BPDUs are

tagged to distinguish the BPDUs of one STG from those of another STG.