Cisco Systems 1000 Series Manual De Usuario

The diagnostic mode provides a more comprehensive user interface for troubleshooting than previous 
routers, which relied on limited access methods during failures, such as ROMmon, to diagnose and 
troubleshoot IOS problems.

The diagnostic mode commands are stored in the nonIOS packages on the Cisco ASR 1000 Series 
Routers, which is why the commands are available even if the IOS process is not working properly. 
Importantly, all the commands available in diagnostic mode are also available in privileged EXEC mode 
on the router even during normal router operation. The commands are entered like any other commands 
in the privileged EXEC command prompts when used in privileged EXEC mode.

Entering a question mark (?) at the CLI prompt displays a list of commands available for each command 
mode. You can also get a list of keywords and arguments associated with any command by using the 
context-sensitive help feature.

To get help specific to a command mode, a command, a keyword, or an argument, use one of the 
commands listed in 

This section provides an example of how to display syntax for a command. The syntax can consist of 
optional or required keywords and arguments. To display keywords and arguments for a command, enter 
a question mark (?) at the configuration prompt or after entering part of a command followed by a space. 
The Cisco IOS XE software displays a list and brief description of available keywords and arguments. 
For example, if you were in global configuration mode and wanted to see all the keywords or arguments 
for the arap command, you would type arap ?.

The <cr> symbol in command help output stands for “carriage return.” On older keyboards, the carriage 
return key is the Return key. On most modern keyboards, the carriage return key is the Enter key. The 
<cr> symbol at the end of command help output indicates that you have the option to press Enter to 
complete the command and that the arguments and keywords in the list preceding the <cr> symbol are 
optional. The <cr> symbol by itself indicates that no more arguments or keywords are available and that 
you must press Enter to complete the command.

 shows examples of how you can use the question mark (?) to assist you in entering commands.

Provides a brief description of the help system in any 
command mode.

Provides a list of commands that begin with a particular 
character string. (No space between command and question 
mark.)

Completes a partial command name.

Lists all commands available for a particular command mode.

Lists the keywords or arguments that you must enter next on 
the command line. (Space between command and question 
mark.)