NE80 connects to CISCO through POS 622. Check the information on POS622 at NE80, and both physical layer and protocol layer of the port are down.
1. Check the configurations of POS port, and the clock is set to active. After it is changed to slave, the physical layer is still down.
2. Use command at POS to configure a loop, and the problem persists.
3. Change the clock of POS port to active, and then configure a loop by using software at local; the physical layer is up, indicating the port is normal.
4. Cancel the local loop of software, and set the clock of POS port to SLAVE; after the POS is reset, the physical layer of POS port is up, but the problem on protocol layer persists.
5. Check the configurations of CISCO equipment with the help of customer, and it is found that the IP address of POS port of NE80 is the same as that of CISCO equipment.
6. Change the IP address of POS port of NE80, and the physical layer is up then; NE80 could ping through to the port address of POS of equipment at the peer.
1. The possible reasons for down physical layer include: POS port iis problematic; transmission equipment fails (POS port does not receive the optics transmitted by transmission equipment); the configuration is problematic.
2. The possible reasons for down protocol layer include: the setting for IP address is false; transmission equipment does not communicate.
1. Perform loop test through software, and the clock of POS port must be set to active.
2. Connect the transmission equipment with NE80, and the clock of NE80 is set to SLAVE, and that on lines is taken as active.