Specifications

CSU/DSU MS DBU

12. Testing and Troubleshooting

12.1 Test Overview

The CSU/DSU MS DBU performs a variety of diagnostic functions that isolate

portions of the circuit to identify the source of the problem. Tests may be initiated

and terminated through the front panel, VT100 terminal, SNMP, or TELNET.

In asynchronous mode, AT commands can control the testing from the DTE

interface. For synchronous operation, V.25 bis commands can provide test control.

The unit also responds to standard DDS network tests initiated from telco test

centers. In addition, it can run several tests such as local and remote loopbacks

to aid in problem isolation. See Figure 12-1.

Figure 12-1. Normal Operation Before Initiating Loopback Test.

CAUTION

All diagnostic tests disrupt data flow.

12.1.1 I

NITIATING A

EST

Initiate tests using the following procedure:

1. Select Test from the Main menu by pressing 2, then press Enter.

2. Specify local, remote, or DBU testing by selecting the corresponding number,

followed by Enter.

3. Use the Up and Down arrows to view test options.

LOCAL

DSU/CSU

REMOTE

DSU/CSU

DTE DTE

TELCO