Hello @yutashimamura2920 ,
the problem with the modem attached to the console line is that you cannot configure modem control on the console line and as long as the two modems are connected, you will always have access to the console line. The only possibility is to hangup the modem from the remote site.
Now, if you were to connect the modem to the AUX line, you can configure on this line modem control:
device(config-line)#modem dialin
this gives you the possibility to hangup the modem when you issue the clear line aux 0 command.
For a complete functional config you will also need the following line commands:
exec
databits 8
stopbits 1
parity none
speed 9600
Regards, LG
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