Setting Parameters for Interworking Between a Huawei Datacom Device and a Non-Huawei Device
Context
To implement interworking between a Huawei datacom device and a non-Huawei device, configure the fast transition mode according to the Proposal/Agreement mechanism of the non-Huawei device. The switch supports the following modes on the Proposal/Agreement mechanism:
- Enhanced mode: The port participates in calculation of the root port when calculating the synchronization flag bit.
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 a root port and blocks all non-edge ports.
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.
The downstream device sends an Agreement message to the upstream device. After receiving the Agreement message, the upstream device sets the port connected to the downstream device as a designated port, and the designated port transitions to the Forwarding state.
- Common mode: The port ignores the root port when calculating the synchronization flag bit.
An upstream device sends a Proposal message to a downstream device, requesting fast transition. After receiving the Proposal message, the downstream device sets the port connected to the upstream device as a root port and blocks all non-edge ports. The root port then transitions to the Forwarding state.
The downstream device sends an Agreement message to the upstream device. After receiving the Agreement message, the upstream device sets the port connected to the downstream device as a designated port, and the designated port transitions to the Forwarding state.
On a network running VBST protocol, a Huawei datacom device and the connected non-Huawei device may fail to communicate if they use different Proposal/Agreement modes. The Huawei datacom device can select the same mode as that on the non-Huawei device to implement interworking.
If Huawei datacom device and HanDreamnet switch are deployed on the VBST network, non-standard STP/RSTP packets sent by the HanDreamnet switch may cause temporary loops. Therefore, the Huawei datacom device interface needs to be configured to discard non-standard STP/RSTP packets to prevent temporary loops.
Pre-configuration Tasks
Before setting parameters for interworking between a Huawei datacom device and a non-Huawei device, perform the task of Configuring VBST.
Procedure
- Run system-view
The system view is displayed.
- Run interface interface-type interface-number
The view of the interface that participates in spanning tree calculation is displayed.
- Run stp no-agreement-check
The common mode is configured.
By default, the enhanced mode is used on a port.
- (Optional) Run stp agreement-legacy
The interface is configured to discard non-standard STP/RSTP packets sent by the HanDreamnet switch.
By default, Huawei datacom device interface does not discard non-standard STP/RSTP packets sent by the HanDreamnet switch.
- (Optional) Run stp revertive slow
The interface is configured the delay in revertive switching during VBST calculation on a port.
When a VBST-enabled switch interworks with a PVST-enabled third-party device that does not support P/A negotiation, negotiation is asynchronous. As a result, the network convergence time is long. If the remote device is the root bridge and the VBST-enabled switch provides the alternate port in addition to the interconnected port, you can enable the delay in revertive switching on the interconnected interface. The delay is calculated as follows: 2 * Forward Delay + 8s After the delay function is enabled, the remote interface first completes spanning tree calculation when the port status changes. Then the local interface performs spanning tree status switching. During status switching, services are not interrupted.
After the delay in revertive switching is enabled on a port, this function takes effect for all VLANs that the interface joins. If there is no alternate port in the VLAN where the interconnected port belongs, the port needs to wait for the delay for recovery. Exercise caution when you run this command in this situation.