Shell - 3Com Switch 4500 Family Manual

By default, password authentication is performed when a user logs in through a modem or Telnet. If no
password is set, the user cannot establish a connection with the switch.
Examples
# Set the local password of VTY 0 to "123".
<Sysname> system-view
System View: return to User View with Ctrl+Z.
[Sysname] user-interface vty 0
[Sysname-ui-vty0] set authentication password simple 123

shell

Syntax
shell
undo shell
View
User interface view
Parameters
None
Description
Use the shell command to enable terminal services.
Use the undo shell command to disable terminal services.
By default, terminal services are disabled in all user interfaces.
Note the following when using the undo shell command:
Terminal services cannot be disabled in AUX user interfaces.
This command is unavailable in the current user interface.
The execution of this command requires user confirmation.
Examples
# Disable terminal services in VTY 0 through VTY 4 (assuming that you log in through an AUX user
interface).
<Sysname> system-view
System View: return to User View with Ctrl+Z.
[Sysname] user-interface vty 0 4
[Sysname-ui-vty0-4] undo shell
% Disable ui-vty0-4 , are you sure ? [Y/N]y
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