3Com 3C63311 Reference Guide - Page 181

Managing System Alarms 169 Alarms Common to Several Interfaces Table 27 describes major alarms common to several PathBuilder S330/S310 interfaces. Table 27 Alarms Common to Several Modules Alarm Alarm Indication Signal(AIS) Far End Receive Failure FEAC Loopback Idle Signal In Band Loopback Link Down Link Up Local Card Loopback Loss of Cell Delineation(LOCD) (continued) Meaning Troubleshooting Steps An incoming alarm indication signal (AIS) indicates a LOS problem is occurring on the line upstream of the equipment connected to this port. Check your locally connected DS3/E3/OC3 equipment, or ask your service provider to trace the source of the AIS signal. The far end equipment has a problem with the signal it is receiving from the PathBuilder device. Check for a defective cable between the PathBuilder device network interface port and your service provider's network interface unit. An open transmit line can cause this condition. Check the LBO setting of the port. A DS3 overhead function that Check with your service provider to allows the system to be determine the reason for the loopback. enabled or disabled for responding to Far End Alarm Condition commands from the central office. When enabled, the DS3 line loopback is put up upon instruction from the central office. The system removes the loopback upon instruction or after 15 minutes. The line has not been Check the configuration of the terminal provisioned for service. No data equipment, or have your service will pass on a line with an idle provider check their equipment and signal. make sure it is provisioned for service. A loopback is configured on the port. Loopbacks are for troubleshooting only and should not be present under normal operating conditions. If you are not troubleshooting the port, turn off the loopback. Summary informational alarm Information only. to indicate one or more alarms on this link are active. Summary informational alarm Information only. to indicate all alarms on the physical link are cleared. A loopback is configured on the port. Loopbacks are for troubleshooting only and should not be present under normal operating conditions. If you are not troubleshooting the port, turn off the loopback. Loss of cell delineation-possibly a framing or timing problem. Check the reference clock source. Compare parameters between local and service provider end. Check the physical layer.