Cisco CPA2501, User Manual

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4-16 Router Installation and Configuration Guide
Cisco IOS Software Basics
Almost every configuration command also has a no form. In general, use the no form to
disable a feature or function. Use the command without the keyword no to reenable a
disabled feature or to enable a feature that is disabled by default. For example, IP routing
is enabled by default. To disable IP routing, enter the no ip routing command and enter
ip routing to reenable it. The Cisco IOS software command reference publication provides
the complete syntax for the configuration commands and describes what the no form of a
command does.
1. You can modify the configuration register value using the config-reg configuration command. Refer to the Cisco IOS configuration
guide for more information.
Interface
configuration Interface configuration commands
modify the operation of an interface
such as an Ethernet, Token Ring, or
serial port. Many features are
enabled on a per-interface basis.
Interface configuration commands
always follow an interface global
configuration command, which
defines the interface type. From global configuration mode,
enter the interface type number
command. For example, enter the
interface serial 0 command to
configure the serial 0 interface. Router(config-if)#
ROM monitor ROM monitor commands are used
to perform low-level diagnostics.
You can also use the ROM monitor
commands to recover from a system
failure and stop the boot process in a
specific operating environment.
1
From privileged EXEC mode,
enter the reload EXEC command.
Press Break during the first
60 seconds while the system is
booting. >
Table 4-2 Cisco IOS Operating Modes (Continued)
Mode of
Operation
Usage How to Enter the Mode Prompt