3Com MSR 50 Series Configuration Manual page 802

802 C 53: T
HAPTER ERMINAL
A T
CCESS ROUBLESHOOTING
Figure 228 Terminal access joint detail
For detailed cable descriptions, refer to the related manuals.
2 3-wire, 5-wire, and 8-wire asynchronous serial interface cables
When a 3-wire asynchronous serial interface cable is used, since dsr/dtr and flow
control signal lines are absent, you must use the undo detect dsr-dtr and
flow-control none (or flow-control software inbound) commands on the
asynchronous serial interface, to not detect the dsr/dtr signals so that the
asynchronous interface automatically enters the up state, and to not detect
hardware flow control signals by adopting software flow control or no flow
control.
When a 5-wire asynchronous serial interface cable is used, since flow control
signal lines are absent, you must use the flow-control none or flow-control
software inbound command on the asynchronous interface, to not detect
hardware flow control signals by adopting software flow control or no flow
control instead.
When a 8-wire asynchronous serial interface cable is used, all the required signal
lines are available; therefore, you do not need to configure the above-mentioned
commands on the asynchronous interface.
Check whether the router and Unix server can ping each other
1 If yes
The WAN line between the router and the Unix server functions well, and the
criterion is satisfied for the router to establish a TCP connection to the server. Refer
to "Check whether the main ttyd process and its child processes are present" on
page 803.
2 If not
Check the configuration of the WAN interface of the router, the WAN line
provided by the ISP, and the router related parameters on the router and server.