Specifications

configure stpd default-encapsulation
ExtremeWare XOS 10.1 Command Reference Guide 373
configure stpd default-encapsulation
configure stpd <stpd_name> default-encapsulation [dot1d | emistp |
pvst-plus]
Description
Configures the default encapsulation mode for all ports added to the specified STPD.
Syntax Description
Default
All ports are in emistp mode, except those in STPD s0, whose default setting is 802.1d mode.
Usage Guidelines
After you have created the STPD with a unique name, the keyword stpd is optional.
Care must be taken to ensure that ports in overlapping domains do not interfere with the orderly
working of each domain’s protocol.
You can specify the following STP encapsulation modes:
• dot1d—This mode is reserved for backward compatibility with previous STP versions. BPDUs are
sent untagged in 802.1d mode. Because of this, any given physical interface can have only one STPD
running in 802.1d mode.
• emistp—This mode sends BPDUs with an 802.1Q tag having an STPD instance Identifier (StpdID) in
the VLANid field.
• pvst-plus—This mode implements PVST+ in compatibility with third-party switches running this
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.
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 one of the member VLANs in that STP domain, and that
VLAN cannot belong to another STPD.
NOTE
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.
stpd_name Specifies an STPD name on the switch.
dot1d Specifies the STP encapsulation mode of operation to be 802.1d.
emistp Specifies the STP encapsulation mode of operation to be EMISTP.
pvst-plus Specifies the STP encapsulation mode of operation to be PVST+.