3Com Switch 4500 Family Manual page 827

Note that:
To display the debugging information on the terminal, you need to configure both the terminal
debugging and terminal monitor commands.
If you execute the undo terminal monitor command, you will disable the monitoring of the log,
trap, and debugging information on the current terminal. Thereby, no log, trap, or debugging
information will be displayed on the terminal.
The configuration of the terminal debugging command takes effect for the current connection
only. If the terminal re-establishes a connection, the terminal display for debugging information is
disabled.
Related commands: debugging.
Examples
# Enable terminal display for debugging information.
<Sysname> terminal debugging
% Current terminal debugging is on
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