Specifications

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Cisco AS5800 Operations, Administration, Maintenance, and Provisioning Guide
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APPENDIX A
Advanced Quick Reference
This appendix provides quick reference configurations for the advanced Cisco AS5800 user and system
administrator who need to rapidly modify system functionality or enhance system performance.
Interface and/or protocol configurations addressed in this section are listed categorically and sequenced
logically by operation.
Remember, Cisco routers are configured using a command line interface (CLI) from a user interface,
known as a port, that provides hardware connectivity. Routers are accessed from the routers console port
or by Telnetting into the routers interface from another host. A command interpreter, called EXEC, is
employed by the operating system to translate and execute Cisco IOS commands. This command
interpreter provide the user with privileged mode of access that promotes security to the respective
command levels, restricting users to a subset of mode-specific commands.
• User EXEC mode (5800>) provides restricted access and limits router configuration or
troubleshooting. At this level, miscellaneous functionality is performed, such as viewing system
information, obtaining basic router status, changing terminal settings, or establishing remote device
connectivity.
• Privileged EXEC mode (5800#) includes user mode functionality and provides unrestricted access.
It is used exclusively for router configuration, debugging, setting operating system (OS) parameters,
and retrieving detailed router status information.
– Global configuration mode [5800(config)#] is a preliminary configuration mode that
recognizes commands affecting the whole router. Some of these commands cause the router to
enter other configuration modes that recognize even more detailed commands.
• There are many modes of configuration within global configuration mode that determine the type of
configuration desired, such as interface configuration
[5800(config-if)#]. Each configuration
command mode restricts the user to a subset of mode-specific commands that individualize and
secure a router.
• ROM monitor mode (> or rommon>) is a CLI allowing router configuration if the router does not
find a valid system image or if the bootup sequence is interrupted during startup.
The end (Ctrl-Z) command provides an escape from any configuration command mode: Terminal
[5800(config)#], Interface [5800(config-if)#], Line [5800(config-line)#], Controller
[5800(config-controll)#], Router [5800(config-router)#], etc., to privileged EXEC mode
(5800#). The exit command provides an escape from any configuration command mode to one
command prompt level higher, or completely out of the command line interface if you are in privileged
EXEC or user EXEC mode. The disable command provides an escape from privileged EXEC mode to
user EXEC mode. The logout command provides a complete escape out of the command line interface
if you are in privileged EXEC or user EXEC mode.