The CLI Help Features

Typing ? in the console displays help for all commands supported by the CLI mode. In other words, the information supplied by using help depends on the CLI mode. If ? is typed in user mode, the commands allowed only in privileged exec mode are not displayed. Also, help is available in configuration mode; only configuration commands are displayed in that mode of operation. IOS stores the commands that you type in a history buffer. The last ten commands are stored by default. You can change the history size with the terminal history size size command, where size is the number of IOS commands for the CLI to store; this can be set to a value between 0 and 256. You can then retrieve commands so that you do not have to retype the commands.