3Com 5500-EI PWR Reference Manual page 256

undo stp interface interface-type interface-number no-agreement-check
View
System view, Ethernet port view
Parameters
interface-type: Port type.
interface-number: Port number.
Description
Use the stp no-agreement-check command to enable the rapid transition feature on the current
port in Ethernet port view. Use the stp no-agreement-check command to disable the rapid
transition feature on the current port in Ethernet port view.
Use the stp interface no-agreement-check command to enable the rapid transition feature on the
specified port in system view. Use the undo stp interface no-agreement-check command to
disable the rapid transition feature on the specified port in system view.
By default, the rapid transition feature is disabled on a port.
Some manufactures' switches adopt proprietary spanning tree protocols that are similar to RSTP in the
way to implement rapid transition on designated ports. When a switch of this kind operates as the
upstream switch of a 3Com switch 5500-EI running MSTP, the upstream designated port fails to change
their states rapidly.
The rapid transition feature aims to resolve this problem. When a 3Com switch 5500-EI running MSTP
is connected in the upstream direction to another manufacture's switch adopting proprietary spanning
tree protocols, you can enable the rapid transition feature on the ports of the switch 5500-EI operating
as the downstream switch. Among these ports, those operating as the root ports will then actively send
agreement packets to their upstream ports after they receive proposal packets from the upstream
designated ports, instead of waiting for agreement packets from the upstream switch. This enables
designated ports of the upstream switch to change their states rapidly.
The rapid transition feature can be enabled on only root ports or alternate ports.
You can enable the rapid transition feature on the designated port. However, the feature does not
take effect on the port.
Examples
# Enable the rapid transition feature on Ethernet 1/0/1.
Enable the rapid transition feature on Ethernet 1/0/1 in Ethernet port view.
<Sysname> system-view
System View: return to User View with Ctrl+Z.
[Sysname] interface Ethernet 1/0/1
[Sysname-Ethernet1/0/1] stp no-agreement-check
Enable the rapid transition feature on Ethernet 1/0/1 in system view.
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