Huawei AR530 series Configuration Manual page 224

Huawei AR530&AR550 Series Industrial Switch Routers
Configuration Guide - Ethernet Switching
Context
A switching device supports the following Proposal/Agreement modes:
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On an STP network, if a Huawei switching device is connected to a non-Huawei device that
uses a different Proposal/Agreement mechanism, the two devices may fail to interoperate with
each other. Select the enhanced mode or common mode based on the Proposal/Agreement
mechanism of the non-Huawei device.
Pre-configuration Tasks
Before setting parameters for interoperation between Huawei and non-Huawei devices,
configure basic STP/RSTP functions.
Procedure
Step 1 Run:
system-view
The system view is displayed.
Step 2 Run:
interface interface-type interface-number
The view of an interface participating in spanning tree calculation is displayed.
Step 3 Run:
stp no-agreement-check
The common fast transition mode is specified.
Issue 01 (2014-11-30)
Enhanced mode: The device determines the root port when it calculates the synchronization
flag bit.
1. An upstream device sends a Proposal message to a downstream device to request fast
state 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 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 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 designated port transitions to the Forwarding state.
Common mode: The device ignores the root port when it calculates the synchronization
flag bit.
1. An upstream device sends a Proposal message to a downstream device to request fast
state 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 root port transitions to the Forwarding state.
2. The downstream device 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 designated port transitions to the Forwarding state.
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6 STP/RSTP Configuration
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