We have an Cisco device. We want to configure it from command line interface. How can we accomplish that?

Connecting Device

There is different ways to connect device. It can be changed according to device capabilities. But command line interface is de facto for configuration. We connect to device with telnet.

$ telnet 10.0.0.1

Unprivileged Mode

Cisco devices have generally 3 modes to administrator them. The least privileged mode is unprivileged mode. Where there is minimal and no configuration related commands like ping.

Router>? Exec commands: access-enable Create a temporary Access-List entry access-profile Apply user-profile to interface atmdx Test ATMDX system attach attach to system component clear Reset functions connect Open a terminal connection crypto Encryption related commands. disable Turn off privileged commands disconnect Disconnect an existing network connection do-exec Mode-independent "do-exec" prefix support enable Turn on privileged commands exit Exit from the EXEC help Description of the interactive help system lat Open a lat connection lig LISP Internet Groper lock Lock the terminal login Log in as a particular user logout Exit from the EXEC mrinfo Request neighbor and version information from a multicast router mstat Show statistics after multiple multicast traceroutes

Enable Mode

Enable mode have more capabilities according to unprivileged mode. But network related configıration van not be done from this mode.

We enter enable mode like below

Router>enable Router#

Here is some help about enable mode commands

Router#? Exec commands: access-enable Create a temporary Access-List entry access-profile Apply user-profile to interface access-template Create a temporary Access-List entry alps ALPS exec commands archive manage archive files atmdx Test ATMDX system attach attach to system component auto Exec level Automation beep Blocks Extensible Exchange Protocol commands bfe For manual emergency modes setting calendar Manage the hardware calendar call-home Call-Home commands cd Change current directory chkflash Check flash filesystem clear Reset functions clock Manage the system clock cns CNS agents configure Enter configuration mode connect Open a terminal connection connectedapps Connected applications related commands copy Copy from one file to another

Configuration Mode

Configuration is highest level of Cisco IOS. This mode is level 15. We can do anything we want in the device. Manage interfaces, change routing protocol values, enable stp etc.

Router(config)#? Configure commands: aaa Authentication, Authorization and Accounting. access-list Add an access list entry alias Create command alias alps Configure Airline Protocol Support ancp Configure ANCP apollo Apollo global configuration commands appletalk Appletalk global configuration commands arap Appletalk Remote Access Protocol archive Archive the configuration arp Set a static ARP entry async-bootp Modify system bootp parameters auto Configure Automation banner Define a login banner bba-group Configure BBA Group beep Configure BEEP (Blocks Extensible Exchange Protocol) bfd BFD configuration commands bfd-template BFD template configuration boot Modify system boot parameters bridge Bridge Group. bstun BSTUN global configuration commands ...

How to Configure Cisco Device and User Modes Infografic