Extreme Networks ExtremeWare XOS Command Reference Manual page 1176

ExtremeWare XOS 11.5 supports only the Summit X450 family of switches and the BlackDiamond 8800 series switch.
STP Commands
You might be attempting to add:
Another 802.1D mode STP port to a physical port that already contains an 802.1D mode STP port
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(only one 802.1D encapsulation STP port can be configured on a particular STP port)
A carrier VLAN port to a different STP domain than the carrier VLAN belongs
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A VLAN/port for which the carrier VLAN does not yet belong
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NOTE
This restriction is only enforced in an active STP domain and when you enable STP to make sure you have a
legal STP configuration.
Care must be taken to ensure that ports in overlapping domains do not interfere with the orderly
working of each domain's protocol.
By default, when the switch boots for the first time, it automatically creates a VLAN named default with
a tag value of 1 and STPD s0. The switch associates VLAN default to STPD s0. All ports that belong to
this VLAN and STPD are in 802.1D encapsulation mode with autobind enabled. If you disable autobind
on the VLAN default, that configuration is saved across a reboot.
Naming Conventions. If your STPD has the same name as another component, for example a VLAN,
Extreme Networks recommends that you specify the identifying keyword as well as the name. If your
STPD has a name unique only to that STPD, the keywords
STP Encapsulations Modes. You can specify the following STP encapsulation modes:
—This mode is reserved for backward compatibility with previous STP versions. BPDUs are
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dot1d
sent untagged in 802.1D mode. Because of this, any given physical interface can have only one STPD
running in 802.1D mode.
This encapsulation mode supports the following STPD modes of operation: 802.1D, 802.1w, and
MSTP.
—This mode sends BPDUs with an 802.1Q tag having an StpdID in the VLANid field.
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emistp
This encapsulation mode supports the following STPD modes of operation: 802.1D and 802.1w.
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pvst-plus
version of STP. The STPDs running in this mode have a one-to-one relationship with VLANs, and
send and process packets in PVST+ format.
This encapsulation mode supports the following STPD modes of operation: 802.1D and 802.1w.
These encapsulation modes are for STP ports, not for physical ports. When a physical port belongs to
multiple STPDs, it is associated with multiple STP ports. It is possible for the physical port to run in
different modes for different domains for which it belongs.
MSTP STPDs use 802.1D BPDU encapsulation mode by default. To ensure correct operation of your
MSTP STPDs, do not configure EMISTP or PVST+ encapsulation mode for MSTP STPDs.
STPD Identifier. An StpdID is used to identify each STP domain. You assign the StpdID when
configuring the domain. An StpdID must be identical to the VLANid of the carrier VLAN in that STPD
and that VLAN cannot belong to another STPD.
MSTP uses two different methods to identify the STPDs that are part of the MSTP network. An instance
ID of 0 identifies the Common and Internal Spanning Tree (CIST). The switch assigns this ID
automatically when you configure the CIST STPD. A multiple spanning tree instance identifier identifies
each STP domain that is part of an MSTP region. You assign the MSTI ID when configuring the STPD
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—This mode implements PVST+ in compatibility with third-party switches running this
and are optional.
stpd vlan
ExtremeWare XOS 11.5 Command Reference Guide