The version of NE40 is VRP3.10-2317. Connect four 155m POS interfaces of NE40 with router of C company and using PPP encapsulation connection succeeds. The link layer state is UP and the protocol layer state UP. Test POS interface, connect HDLC encapsulation with router of C company and it succeeds. The link layer state and the protocol state are UP. In the deployment of the site, change encapsulation of POS interface as connection of PPP and C Company. Configure link-protocal ppp at NE40 under POS port mode and it is found that the link layer state is UP and the protocol layer state not.
1. Before it has connected with POS of router in C Company. So parameters of POS interface of two ports are consistent. The scramble is ENABAL. POS interface at NE40 chooses SLAVE clock and POS interface of router in C company chooses LINE clock. CRC is 32 and link layer encapsulation is PPP protocol. Configure IP address at two ports and using HDLC succeeds, it indicates that physical link is not problematic.
2. Load VRP3.10-2317 patch and shutdown POS interface of NE40 and then UNDO SHUTDOWN. The link layer state is UP and the protocol layer state is still DOWN. The patch is RUN.
3. Re-encapsulate PPP protocol at POS interface LINK-PROTOCAL PPP and the protocol layer state is UP.
1. It is possible that some parameters at POS interface of two routers mismatch, such as scramble, CRC and encapsulated protocol.
2. Specification fault.
3. Unknown reason.
If POS interface of 8011 product VRP3.10-2317 version is encapsulated PPP the first time, POS interfaces of two connection routers configure and can succeed. However, change POS encapsulation as HDLC and then PPP, the protocol layer state cannot be UP. It needs load VRP3.10-2317SP01 patch and encapsulate protocol of link layer of POS with PPP. And then the protocol is UP.