Extreme Networks Summit 300-48 - Manual (Page 148)

148 Summit 300-48 Switch Software User Guide
Spanning Tree Protocol (STP)
Figure 16: Tag-based STP configuration
The tag-based network in Figure 16 has the following configuration:
• Switch 1 contains VLAN Marketing and VLAN Sales.
• Switch 2 contains VLAN Engineering and VLAN Sales.
• Switch 3 contains VLAN Marketing, VLAN Engineering, and VLAN Sales.
• The tagged trunk connections for three switches form a triangular loop that is not permitted in an
STP topology.
• All VLANs in each switch are members of the same STPD.
STP can block traffic between switch 1 and switch 3 by disabling the trunk ports for that connection on
each switch.
Switch 2 has no ports assigned to VLAN marketing. Therefore, if the trunk for VLAN marketing on
switches 1 and 3 is blocked, the traffic for VLAN marketing will not be able to traverse the switches.
Configuring STP on the Switch
To configure STP, follow these steps:
1 Create one or more STP domains using the following command:
create stpd <stpd_name>
NOTE
STPD, VLAN, and QoS profile names must all be unique. For example, a name used to identify a VLAN
cannot be used when you create an STPD or a QoS profile.
2 Add one or more VLANs to the STPD using the following command:
config stpd <stpd_name> add vlan <name>
LB48015
Marketing & Sales Marketing, Sales & Engineering
Switch 1
Switch 2
Sales & Engineering
Switch 3