Zhone Technologies 900 - Manual (Page 113)

Data Cards IMACS System Release 5.1.6 4-5
DS0-DP Card DS0-DP Card Error Messages
LB DET
This option allows the card to detect DDS latching loopbacks. When set to off, no loopbacks
can be detected. When set to enab, loopbacks will be detected. When a loopback is detected,
it will be maintained until a loop down is detected. w/to is the same as enab except that if no
loop down is detected after 10 minutes, the loopback will self-terminate. This option only
functions in the DS0-DP mode.
4.4 DS0-DP Card Error Messages
Refer to Appendix B in the System Reference Guide for further information on Error
Messages regarding this card.
4.5 DS0-DP Card Troubleshooting
Problems with a DS0-DP card could indicate a number of causes. Some possibilities are:
• Faulty receiving DTE at the near end (where the problem was first noticed)
• Faulty transmitting DTE at the far (opposite) end
• Faulty cabling between the DTE and DS0-DP card at the near end
• Faulty cabling between the DTE and DS0-DP card at the far end
• T1 or E1 network failure
• Improper card configuration at either end (e.g., time slot and/or WAN port assignments)
Typically, a problem is indicated by a loss of incoming signal on a data port at either end of
the circuit. You can perform numerous tasks to isolate the trouble and clear it. When
troubleshooting transmission problems on a data circuit passing through a DS0-DP card,
follow this general sequence:
1. If all ports are affected, verify that the US/EUR jumper is correctly placed to match the
US/EUR jumper on the chassis.
2. Verify that the T1 or E1 network is working properly by checking for current CGA-Red
and CGA-Yellow alarms. If the network is faulty, the same transmission problem may
exist with the other ports of the same DS0-DP card, and also with the data ports of all
other data cards connected to the same T1 or E1 line. If no CGA alarms are present,
continue with step 3.
3. Verify that the DS0 time slot assignments of the faulty port at both ends of the data
circuit path are correct. Also be sure the port is connected to the proper WAN card and
port at each end. If these assignments are correct, continue with step 4.