System information

Troubleshooting ATM Switching Environments
Book Title
21-444
The following steps describe how to perform a ping test from a LightStream 2020 ATM switch:
Step 1 Log in as root on the LightStream 2020 switch from which you want to send ICMP echo
packets.
Step 2 Enter the ping [packet-size] hostname command (where packet-size is the size of the
packets to send and hostname is the name or IP address of the host). The packet size
argument is optional. The default packet size is 64 bytes.
Step 3 To stop the ping and display a summary of the results, press ^C.
ATM Switching: Trunk Does Not Come Up
Symptom: An ATM trunk does not come up properly and connections cannot be made.
Table 21-4 outlines the problems that might cause this symptom and describes solutions to those
problems.
Table 21-4 ATM Switching: Trunk Does Not Come Up
Possible Problem Solution
Card not configured as a trunk card
Step 1 Check the port at each end of the trunk with the show port
port-number statistics command. Make sure that both ports are
periodically sending cells.
Step 2 Check the Octets Sent field to verify that it is incrementing.
Step 3 If one port never sends trunk-up-down messages, make sure the card
is correctly configured as a trunk card.
Step 4 Make sure that a trunk is configured on port 0. The trunk can be
configured as inactive if desired.
Step 5 If both sides of the trunk show that they are sending cells, find out
which side is not receiving cells. Perform a basic port check as
described in the section “Basic Port Checks” earlier in this chapter.
Incorrect line type Make sure that the line type parameter (dsx3Linetype) is correctly
configured. Check with your carrier for the correct line type for your
connection. Use the show port physical command to display the line type as
well as the following information:
• Port type
• Operational and administrative CSU type
• Operational and administrative DCE receive bit rate
• Operational transmit bit rate
• Measured bit rate
• Link transmit utilization rate (data plus control)
• Administrative expected dte rate and operational and administrative net
interface type (dte/dce; these are for low-speed line cards only)
• Operational and administrative protocol
• LC auto enable state and debug level
• Data cell capacity and available capacity
• Call setup retry and backoff times
• Operational maximum frame size
• Modem status (DCD, DSR)