stp no-agreement-check

Function

The stp no-agreement-check command configures the common fast transition mechanism on an interface.

The undo stp no-agreement-check command restores the default fast transition mechanism on an interface.

STP does not support fast transition. By default, for RSTP, MSTP, and VBST, fast transition in enhanced mode is used on a port.

Format

stp no-agreement-check

undo stp no-agreement-check

Parameters

None

Views

Ethernet interface view, GE interface view, XGE interface view, MultiGE interface view, 40GE interface view, 100GE interface view, Eth-Trunk interface view, port group view, 25GE interface view

Default Level

2: Configuration level

Usage Guidelines

Usage Scenario

If Huawei and non-Huawei data communication devices are deployed on a network running a spanning tree protocol, the Huawei devices and non-Huawei devices may fail to communicate with each other, because they have different Proposal/Agreement mechanisms. To address this problem, the stp no-agreement-check command can be used to set a common fast transition mechanism or an enhanced transition mechanism on a port.

Running the stp no-agreement-check command configures a common fast transition mechanism on a port.
Running the undo stp no-agreement-check command configures an enhanced fast transition mechanism on a port.

Precautions

The fast transition mechanism is also called the Proposal/Agreement mechanism. The device currently supports the following modes:

Enhanced mode: The current interface counts a root port when it computes the synchronization flag bit.
1. An upstream device sends a Proposal message to a downstream device requesting fast transition. After receiving the message, the downstream device sets the port connected to the upstream device as the root port and blocks all non-edge ports.
2. The upstream device then sends an Agreement message to the downstream device. After the downstream device receives the message, the root port transitions to the Forwarding state.
3. The downstream device then responds with an Agreement message. After receiving the message, the upstream device sets the port connected to the downstream device as the designated port, and then the status of the designated port changes to Forwarding.
Common mode: The current interface ignores the root port when it computes the synchronization flag bit.
1. An upstream device sends a Proposal message to a downstream device requesting fast transition. After receiving the message, the downstream device sets the port connected to the upstream device as the root port and blocks all non-edge ports. Then, the status of the root port changes to Forwarding.
2. The downstream device then responds with an Agreement message. After receiving the message, the upstream device sets the port connected to the downstream device as the designated port, and then the status of the designated port changes to Forwarding.

Between two interconnected switching devices in a spanning tree, the switching device nearer to the root bridge is the upstream device of the other devices.

Example

# Configure the common fast transition mechanism for the GE0/0/1.

<HUAWEI> system-view

[HUAWEI] interface gigabitethernet 0/0/1

[HUAWEI-GigabitEthernet0/0/1] stp no-agreement-check