how to reset cisco router back to factory default

ometimes our security configuration on a Cisco router is felt not so according to our effectiveness, and therefore we want to replace it with a new configuration is more effective, powerful and more secure. but it is impossible to remove all settings that are stored line by line like no ip access-list extended internet, etc. .., we should be able to delete or overwrite any existing settings with just one or a few steps, how? let’s discuss ..

step 1 : Check the configuration register on the router by issuing the show version command. The configuration register setting is displayed in the last line of the show version command output, and should be set to 0×2102. If this is not the case, enter the config-register 0×2102 command once in global configuration mode

router# configure terminal

router(config)# config-register 0×2102

router(config)# end

router#

If the show version command is issued again, the same line in the command output will have ‘(will be 0×2102 at next reload)‘ appended to the current register setting.

Step 2 : Erase the current start-up configuration on the router with the write erase command

Step 3 : Reload the router with the reload command. When prompted to save the configuration, DO NOT save.

router#reload

System configuration has been modified. Save? [yes/no]: n

Proceed with reload? [confirm]

Step 4 : Once the router reloads, the user will be presented with a ‘System Configuration Dialog’ as shown below. The router is now reset back to the original factory defaults.

— System Configuration Dialog —

Would you like to enter the initial configuration dialog? [yes/no]:

This article is not fully entirely made by www.ionhelp.com but partially excerpted from the website www.cisco.com and several other websites.