NE80 connects to CISCO through POS 155. Check the information on POS622 at NE80, and both physical layer is up, protocol down
CRC packets are received on on both side .
1,check the ip addresses on both side , resuslt is ok
2,make the loop on NE80, on cisco 12410 we can see the loop. it prove the fiber is good
3,make the loop on cisco router, we can not see any loop on NE80.
some reason can result in this issues: SFP module , STM-1 card.
4,change the SFP module ,STM-1 card step by step. the problem is not solved
5,check the STM-1 POS parameter on both side and compare the parameter value . on cisco router , C2 parameters is not cisco defaut vlaue . it is differnet C2 parameter on NE80 (disp interface pos xxx v ).
6,adjust the C2 parameter value on NE80 ,the problems is solved.
The possible reasons for down protocol layer include: the setting for IP address is false; transmission equipment does not communicate. parameter for POS interfafce on both side is not match.
1.for Pos interface the C2 parameters on both must match , otherwise it can cause the infomation on J1 parameter is not correct , the infomation will changed quickly .not fix value.