1. First preview Cisco routers under various security password setting method
a. Console password global configuration mode
router (config) #line console 0 / mode enters the console port
router (config) #password cisco / password provided
router ( config) # login / open password to take effect.
b. into the global configuration code
Router # T config
Router (config) // Open #enable plaintext password password Cisco
router (config) #enable secret cisco // Open cipher text password
c. remote login password
router (config) #line vty 0 4 / to enter the virtual end-user
Router (config) #Password the Cisco
Router (config) #login
2. reset the password without clear configuration (said to be clear, in fact, bypass the default startup mode, change the password and then import process)
A. Line with the console connected to the console, turn on the CRT software, user mode input show version, view the default value of 0x2102 registration, restart the router press ctrl + break / pause button, the system enters rommon mode, modifying the value of register
confreg 0X2142, then the RESET input, to reboot into the router setup configuration mode, prompted to select N, directly enter the configuration mode.
b. into privileged mode enable, input-config running-strartup Copy config
C. password setting mode to enter global password enable / Secret Cisco,
config-Register 0x2102, change the default register value 0x2102.
D. enter user input mode or the current write modified to save a good password runningconfig startup-config (copy runningconfig startup- config), the final restart the router authentication password.
3. The second is to know the password to clear all configuration (restore factory settings), of course, also Clear password together out
a.router # erase startup-config to restore the factory settings
router # reload restart