enable stpd auto-bind

enable stpd stpd_name auto-bind [ {vlan} vlan_name | vlan vlan_list]

Description

Automatically adds ports to an STPD (Spanning Tree Domain) when ports are added to a member VLAN (Virtual LAN).

Syntax Description

stpd_name Specifies an STPD name on the switch.
vlan_name Specifies the name of the VLAN to have autobind enabled.
vlan_list Specifies the VLAN list of IDs to have autobind enabled.

Default

The autobind feature is disabled on user-created STPDs. The autobind feature is enabled on the default VLAN that participates in the default STPD S0.

If you enable autobind and add ports to a member VLAN, those ports are automatically added to the STPD.

Usage Guidelines

If you create an STPD and a VLAN with unique names, the keywords stpd and vlan are optional.

You cannot configure the autobind feature on a network login VLAN.

In an EMISTP or PVST+ environment, when you issue this command, any port or list of ports that you add to the carrier VLAN are automatically added to the STPD with autobind enabled. In addition, any port or list of ports that you remove from a carrier VLAN are automatically removed from the STPD. This allows the STPD to increase or decrease its span as you add ports to or remove ports from a carrier VLAN.

For MSTP (Multiple Spanning Tree Protocol), when you issue this command, any port or list of ports that gets automatically added to an MSTI (Multiple Spanning Tree Instances) are automatically inherited by the CIST. In addition, any port or list of ports that you remove from an MSTI protected VLAN are automatically removed from the CIST. For more information see the section. For more information, see Automatically Inheriting Ports--MSTP Only.

Carrier VLAN

A carrier VLAN defines the scope of the STPD, which includes the physical and logical ports that belong to the STPD and the 802.1Q tag used to transport STP BPDUs in the encapsulation mode is EMISTP or PVST+. 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.

Note

Note

The STPD ID must be identical to the VLAN ID of the carrier VLAN in that STPD.

If you configure MSTP, you do not need a carrier VLAN. With MSTP, you configure a CIST that controls the connectivity of interconnecting MSTP regions and sends BPDUs across the regions to communicate the status of MSTP regions. All VLANs participating in the MSTP region have the same privileges.

Protected VLAN

Protected VLANs are all other VLANs that are members of the STPD. These VLANs “piggyback” on the carrier VLAN. Protected VLANs do not transmit or receive STP (Spanning Tree Protocol) BPDUs, but they are affected by STP state changes and inherit the state of the carrier VLAN. Protected VLANs can participate in multiple STPDs, but any particular port in the VLAN can belong to only one STPD.

Enabling autobind on a protected VLAN does not expand the boundary of the STPD. However, the VLAN and port combinations are added to or removed from the STPD subject to the boundaries of the carrier VLAN.

If you configure MSTP, all member VLANs in an MSTP region are protected VLANs. These VLANs do not transmit or receive STP BPDUs, but they are affected by STP state changes communicated by the CIST to the MSTP regions. MSTIs cannot share the same protected VLAN; however, any port in a protected VLAN can belong to multiple MSTIs.

Automatically Inheriting Ports--MSTP Only

In an MSTP environment, whether you manually or automatically bind a port to an MSTI in an MSTP region, the switch automatically binds that port to the CIST. The CIST handles BPDU processing for itself and all of the MSTIs; therefore, the CIST must inherit ports from the MSTIs in order to transmit and receive BPDUs.

Displaying STP Information

To view STP configuration status of the ports on a VLAN, use the following command:

show {vlan} [vlan_name | vlan_list] stpd

Example

The examples in this section assume that you have already removed the ports from the Default VLAN.

To automatically add ports to an STPD running 802.1D, EMISTP, or PVST+ and to expand the boundary of the STPD, you must complete the following tasks:
  • Create the carrier VLAN.
  • Assign a VLAN ID to the carrier VLAN.
  • Add ports to the carrier VLAN.
  • Create an STPD (or use the default, S0).
  • Enable autobind on the STPDs carrier VLAN.
  • Configure the STPD tag (the STPD ID must be identical to the VLAN ID of the carrier VLAN in the STP domain).
  • Enable STP.

The following example enables autobind on an STPD named s8 after creating a carrier VLAN named v5:

create vlan v5
configure vlan v5 tag 100
configure vlan v5 add ports 1:1-1:20 tagged
create stpd s8
enable stpd s8 auto-bind v5
configure stpd s8 tag 100
enable stpd s8
To automatically add ports to the CIST STPD and to expand the boundary of the STPD, you must complete the following tasks:
  • Create a VLAN or use the Default VLAN. (In this example, the Default VLAN is used.)
  • Create the MSTP region.
  • Create the STPD to be used as the CIST, and configure the mode of operation for the STPD.
  • Specify the priority for the CIST.
  • Enable the CIST.

The following example enables autobind on the VLAN Default for the CIST STPD named s1. (Starting with ExtremeXOS 22.2, before configuring a user-created STP domain for MSTP, you must first disable the STPD "s0" domain, which by default is in the MSTP CIST domain, and change its operational mode to dot1d or dot1w, as only one MSTP CIST domain can be there on a switch.):

disable stpd s0
configure stpd s0 mode dot1d
configure mstp region 1
create stpd s1
configure stpd s1 mode mstp cist
configure stpd s1 priority 32768
enable stpd s1

The following example enables autobind on the VLAN math for the MSTI STPD named s2:

create vlan math
configure vlan math tag 2
configure vlan math add ports 2-3
configure mstp region 1
create stpd s2
configure stpd s2 mode mstp msti 1
configure stpd s2 priority 32768
enable stpd s2 auto-bind vlan math
configure stpd s2 ports link-type point-to-point 5-6
enable stpd s2

History

This command was first available in ExtremeXOS 10.1.

The vlan_list variable was added in ExtremeXOS 16.1.

Platform Availability

This command is available on the Summit X450-G2, X460-G2, X670-G2, X770, and ExtremeSwitching X440-G2, X590, X620, X690, X870 series switches.