Extreme Networks ExtremeWare XOS 11.3, Manual

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STP Rules and Restrictions
ExtremeWare XOS 11.3 Concepts Guide
447
STP Rules and Restrictions
This section summarizes the rules and restrictions for configuring STP as follows:
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The carrier VLAN must span all ports of the STPD.
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The StpdID must be the VLANid of the carrier VLAN; the carrier VLAN cannot be partitioned.
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A default VLAN cannot be partitioned. If a VLAN traverses multiple STPDs, the VLAN must be
tagged.
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An STPD can carry, at most, one VLAN running in PVST+ mode, and its StpdID must be identical
with that VLANid. In addition, the PVST+ VLAN cannot be partitioned.
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The default VLAN of a PVST+ port must be identical with the native VLAN on the PVST+ device
connected to that port.
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If an STPD contains both PVST+ and non-PVST+ ports, that STPD must be enabled. If that STPD is
disabled, the BPDUs are flooded in the format of the incoming STP port, which may be incompatible
with those of the connected devices.
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The 802.1D ports must be untagged; and the EMISTP/PVST+ ports must be tagged in the carrier
VLAN.
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An STPD with multiple VLANs must contain only VLANs that belong to the same virtual router
instance.
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Automatically adding ports to an STPD (known as STP autobind) cannot be configured on a
Netlogin VLAN.
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STP cannot be configured on the following ports:
■
A mirroring target port.
■
A software-controlled redundant port.
■
A Netlogin port.
Configuring STP on the Switch
To configure basic STP:
1 Create one or more STPDs using the following command:
create stpd <stpd_name>
2 Add one or more VLANs to the STPD using the following command:
configure stpd <stpd_name> add vlan <vlan_name> ports [all | <port_list>] {[dot1d
| emistp | pvst-plus]}
3 Define the carrier VLAN using the following command:
configure stpd <stpd_name> tag <stpd_tag>
NOTE
The carrier VLAN’s VLANid must be identical to the StpdID of the STPD.
4 Enable STP for one or more STPDs using the following command:
enable stpd {<stpd_name>}
After you have created the STPD, you can optionally configure STP parameters for the STPD.