Service interrupted on ONT(MA5612) for nearly 3 minutes shown in olt alarm history due to fiber line quality.
Active port detect a los alarm in type-b protect group, and the protect group switched over.
The feed fiber is broken or OLT can not receive any expected optical signals(LOS)
The lofi alarm is detected by hardware ,probable reasons may like following:
Line quality is not good.
Optic fiber be folded by accident.
Type B protection applies to the OLT that has at least two PON ports. Type B protection allows the system to automatically switch to the standby system when the working port fiber is faulty. This protects the backbone optical fiber.
Working and protection PON ports separately check whether their current optical link is functioning properly. However, only one PON port is allowed to transmit optical signals downstream at a time. If both PON ports transmit optical signals, conflict will occur.
When the protection port failed to detect upstream optic signal, the work and protect port will enable sending function of laser in turn in every 10 seconds , until the there is an ont getting online and the upstream optic signal recovered . Which port the ont getting online will recognized as active port and the other as standby. If the port state changed , protect group switch over alarm will be generated .
From the log , there are a lot of bit error and lofi alarm, especially if olt detect lofi alarm, olt will deactive the ont . Beause there is only one ont in this port , then a los alarm will be detected .
Please check whether ma5612 has been updated to V800R308C00SPC500，If not , it’s suggested to .
Please check the line quality if LOFI alarm number increased when query by “display statistics ont-line-quality ” command.