NE40E Router having version V300R002C06B325.There are two NE40E Routers placed at two different places.We need to have the connectivity between them.We should be able to Ping both the Routers.For that the normal configuration ppp is done between them.The bandwidth provided by the customer was STM-16 (2.5 Gbits) and the technology is SDH.
The port was UP but it was showing line protocol down.
First We checked the powers at both the ends it was proper (-7.09db) which was proper.
Secondly we gave Loop at both the ends and checked the connectivity between them.
Thirdly When we gave the Loopback local command at the POS interface we were getting the loopback detected shown in the text when we gave the command disp interface Posx/y/z.
But when we gave Loopback remote command.At the opponent end we were not getting Loopback detected.From this we came to know that there was some problem in the Mapping from the customer end after verifying the Mapping we were able to Ping it successfully.
As the port was Up on both the Router Ends it was Considered that the link is through.But to check the connectivity when Ping command was given between two Routers it was noticed that there was no connection as it was showing Packet Loss.This was due to the Line Protocol which was showing the Status Down.Even when current status was UP.Due to all these LDP was Stopped and hence we could not establish the connection between two NE40E Routers.
Always check the Media & Mapping between the customer end and our (Huawei) end.