Brocade FastIron Ethernet Switch Platform and Layer 2 Switching Configuration Guide - Manual (Page 313)

The commands shown above override the global setting for STP priority and set the priority to 10 for
port 1/1.
Here is the syntax for the global STP parameters.
Syntax: [no] spanning-tree single [ forward-delay value] [hello-time value] | [maximum-age time] |
[priority value]
Here is the syntax for the STP port parameters.
Syntax: [no] spanning-tree single [ ethernet port path-cost value | priority value]
NOTE
Both commands listed above are entered at the global CONFIG level.
Displaying SSTP information
To verify that SSTP is in effect, enter the following commands at any level of the CLI.
device#show span
Syntax: show span [ vlan vlan-id] | [pvst-mode] | [num] | [detail [vlan vlan-id [ethernet port] | num]]
The vlan vlan-id parameter displays STP information for the specified port-based VLAN.
The pvst-mode parameter displays STP information for the device Per VLAN Spanning Tree (PVST+)
compatibility configuration. Refer to
PVST/PVST+ compatibility on page 317.
The num parameter displays only the entries after the number you specify. For example, on a device
with three port-based VLANs, if you enter 1, then information for the second and third VLANs is
displayed, but information for the first VLAN is not displayed. Information is displayed according to
VLAN number, in ascending order. The entry number is not the same as the VLAN number. For
example, if you have port-based VLANs 1, 10, and 2024, then the command output has three STP
entries. To display information for VLANs 10 and 2024 only, enter show span 1 .
The detail parameter and its additional optional parameters display detailed information for individual
ports. Refer to
Displaying detailed STP information for each interface on page 261.
STP per VLAN group
STP per VLAN group is an STP enhancement that provides scalability while overcoming the limitations
of the following scalability alternatives:
• Standard STP - You can configure up to 254 instances of standard STP on a Brocade device. It is
possible to need more instances of STP than this in large configurations. Using STP per VLAN
group, you can aggregate STP instances.
• Single STP - Single STP allows all the VLANs to run STP, but each VLAN runs the same instance of
STP, resulting in numerous blocked ports that do not pass any Layer 2 traffic. STP per VLAN group
uses all available links by load balancing traffic for different instances of STP on different ports. A
port that blocks traffic for one spanning tree forwards traffic for another spanning tree.
STP per VLAN group allows you to group VLANs and apply the same STP parameter settings to all the
VLANs in the group. The following figure shows an example of a STP per VLAN group implementation.
Displaying SSTP information
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