Netgear XCM8806 - 8800 SERIES 6-SLOT CHASSIS SWITCH ユーザーズマニュアル

Domain (STPD). Each STPD has its own root bridge and active path. After an STPD is 
created, one or more VLANs can be assigned to it.

A physical port can belong to multiple STPDs. In addition, a VLAN can span multiple STPDs.

The key points to remember when configuring VLANs and STP are:

Each VLAN forms an independent broadcast domain.

STP blocks paths to create a loop-free environment.

Within any given STPD, all VLANs belonging to it use the same spanning tree.

To create an STPD, use the following command:

create stpd <stpd_name>

To delete an STPD, use the following command:

delete stpd <stpd_name>

For detailed information about configuring STP and various STP parameters on the switch, 
see 

on page 572.

The remainder of this section describes the following topics:

•     Member VLANs 

•     STPD Modes 

•     Encapsulation Modes 

•     STP States 

•     Binding Ports 

•     Rapid Root Failover 

•     STPD BPDU Tunneling 

•     STP and Hitless Failover—Modular Switches Only 

Member VLANs

When you add a VLAN to an STPD, that VLAN becomes a member of the STPD. The two 
types of member VLANs in an STPD are:

Carrier 

Protected 

A carrier VLAN defines the scope of the STPD, which includes the physical and logical ports 
that belong to the STPD and if configured, the 802.1Q tag used to transport Multiple Instance 
Spanning Tree Protocol (EMISTP) or Per VLAN Spanning Tree (PVST+) encapsulated bridge 
protocol data units (BPDUs) (see 

on page 530 for more information 

about encapsulating STP BPDUs). Only one carrier VLAN can exist in a given STPD, 
although some of its ports can be outside the control of any STPD at the same time.