topic description

Huawei digital pass-through switches via OSN1500 pass-through equipment transmission networking, transmission of four devices topology for two chains, digital pass-through four switches topology for the ring structure. The two end points are two S6506 switches and two S3528 switches. After the industry soft engineers start the STP protocol on the digital communication switches, they find that they are divided into two domains. Checking the switch port counts, it is found that there is packet loss.

OSN1500 transmits device alarm messages

There are no relevant alarms on the transmission device.

Processing

After communicating with the digital communication engineers, it is understood that the broad STP protocol has three modes: MSTP (Multiple Spanning Tree Protocol), RSTP (Rapid Spanning Tree Protocol), and STP (Spanning Tree Protocol), which are theoretically compatible with each other, i.e., STP can be transmitting RSTP and MSTP, and RSTP can be transmitting MSTP.

However, the query OSN products related characteristics of the document, our OSN products currently only support RSTP, STP, and the realization, can not be docked with the MSTP, for OSN data single board inherent defects.

So far, after coordinating the field engineer to change the STP protocol mode of the docking switch to RSTP, the fault disappeared.

Root Cause

Since there is a clear record of sending packets on the digital communication equipment, but there is no record of receiving packets. It can be basically determined that the relevant packet was dropped on the transmission device.

Recommendation and Summary

Due to the native compatibility of MSTP, RSTP, and STP, the STP protocol mode of the digital communication equipment is MSTP by default, but the data veneer implementation of Huawei OSN equipment has defects that prevent it from transmitting MSTP protocol messages, so it is necessary to change the relevant configuration on the docking switch. When explaining to the customer, you can blur the compatibility between MSTP and RSTP and emphasize that our equipment does not support MSTP (Multiple Spanning Tree Protocol) to avoid customer backlash.

The related technical information and SDH equipment troubleshooting procedures in this chapter are collected and organized by Shenzhen Optical Transmission Network Technology Company Limited ( www.opticaltrans.com), please retain! Our company specializes in Huawei SDH optical transmission equipment, SDH transmission equipment sales.