Troubleshooting guide

5-53
ATM and Layer 3 Switch Router Troubleshooting Guide
OL-1969-02
Chapter 5 Troubleshooting Switch Router ATM Interface Connections
Troubleshooting Channelized DS3 and E1 Frame Relay Interfaces
Step 3 Check the Input cells and Output cells fields. If the errors and the input and output difference exceed
0.5 to 2.0 percent of traffic on the interface, the interface is experiencing congestion and dropping cells.
Step 4 Check the AAL5 crc errors field. If the errors and the input and output difference exceed 0.5 to 2.0
percent of traffic on the interface, check for the following:
• Many CRC errors, but not many collision, indicates excessive noise.
• Cables damage. If you are using UTP cables, make sure you are using category 5 cables and not
another type, such as category 3.
If you determine that the physical interface is configured incorrectly, refer to the “Configuring
Interfaces” chapter in the ATM Switch Router Software Configuration Guide.
If the interface is still not operating correctly proceed with the troubleshooting process in Chapter 6,
“Troubleshooting Switch Router ATM Network Connections.”
Troubleshooting Channelized DS3 and E1 Frame Relay
Interfaces
This section describes specific processes and commands used to troubleshoot the channelized DS3
(CDS3) Frame Relay port adapter and channelized E1 (4CE1) Frame Relay port adapter.
Port Adapter LEDs
The port adapter faceplate LEDs provide status information for individual channelized DS3 and E1
Frame Relay port adapter coaxial interface connections of the port adapter. The LEDs are described in
Table 5-13.
Table 5-13 CDS3 Frame Relay Adapter LEDs
LED State Description
CD (carrier detect) Off
Green
Carrier detect signal not received
Carrier detect signal received
RX (receive) Off
Flashing green
Red
LOS
1
or shutdown
Cells being received
Alarm (LOF
2
, LCD
3
, AIS
4
)
1. LOS = loss of signal
2. LOF = loss of frame
3. LCD = loss of cell delineation
4. AIS = alarm indication signal
TX (transmit) Off
Flashing green
Steady yellow
No transmit line activity
Cells being transmitted
Alarm FERF
5
5. FERF = far-end receive failure