CISCO+IOS


 * __ Straight from Cisco - Network Fundamentals - Chapter 11 __**

he CLI uses a hierarchical structure for the modes. In order from top to bottom, the major modes are:
 * User executive mode (User executive mode appears as: **Router>** )
 * Privileged executive mode (Privileged executive mode appears as: **Router#** )
 * Global configuration mode (Global configuration mode appears as: **Router(config)#** )
 * Other specific configuration modes



Commands are used to execute an action, and the keywords are used to identify where or how to execute the command.


 * __Commands List__**
 * **ena / enable** = access privileged mode
 * **disable** = exit privileged mode
 * **Switch(config-if)#description Interface to Building a LAN** = Add the description 'Interface to Building a LAN' to an interface.
 * **?** = Help
 * **Tab** - Completes the remainder of the command or keyword
 * **Ctrl-R** - Redisplays a line
 * **Ctrl-Z** - Exits configuration mode and returns to the EXEC
 * **Down Arrow** - Allows user to scroll forward through former commands
 * **Up Arrow** - Allows user to scroll backward through former commands
 * **Ctrl-Shift-6** - Allows the user to interrupt an IOS process such as ping or traceroute
 * **Ctrl-C** - Aborts the current command and exits the configuration mode
 * **Ctrl-P** = (Up Arrow Equivalent) Scroll Up Through Previous Commands
 * **Ctrl-N** = (Down Arrow Equivalent) Scroll Down Through Previous Commands
 * **Router#sh int =** Show Interfaces
 * **Router#show interfaces serial 0/1** = Show Interface Serial 0/1 (Use Specific Interface)
 * **show version** = Shows Software version / Hardware and Device Information
 * **show ip interfaces** = shows all the interfaces on the router
 * **show ip interface brief** = shows a quick summary of the interfaces
 * **exit**
 * **end**
 * **Router#copy running-config startup-config** = save the running configuration to startup configuration.
 * **Router(config)# hostname //name you want to use// =** Change Hostname
 * **Router(config)# no hostname** = Remove Hostname
 * service password-encryption
 * **Router#****copy running-config tftp**
 * **Router#****copy startup-config tftp**
 * **Router#erase startup-config =** Clear the existing configuration (the running config I'd think)
 * C:**host1>arp -a** = Show the ARP cache
 * **C:host1>arp -d** = Clear the ARP cache
 * **Sw1-2950#show mac-address-table** = Show Mac Address Table

__**Set Console Password**__
 * **Switch(config)#line console 0**
 * **Switch(config-line)#password //password//**
 * **Switch(config-line)#login**
 * **Switch(config-line)#logg syn**
 * **Switch(config-line)#login**

__**Set Enable Passwords**__ Note: If no enable password or enable secret password is set, the IOS prevents privileged EXEC access from a Telnet session.
 * **Router(config)#enable password password**
 * **Router(config)#enable secret password**

__**Set Telnet Password**__ Note: By default, many Cisco devices support five VTY lines that are numbered 0 to 4.
 * **Router(config)#line vty 0 4**
 * **Router(config-line)#password //password//**
 * **Router(config-line)#login**


 * __Set Message Of The Day (motd)__**
 * **Switch(config)#banner motd # //message// #**


 * __Reload Statup-config__**
 * **Router#reload**
 * **System configuration has been modified. Save? [yes/no]: n**

//Note:// //The Delete key, used to erase to the right of the cursor, is not recognized by terminal programs.//
 * __C L I Editing:__**
 * **Tab** - Completes a partial command name entry.
 * **Backspace** - Erases the character to the left of the cursor.
 * **Ctrl-D** - Erases the character at the cursor.
 * **Ctrl-K** - Erases all characters from the cursor to the end of the command line.
 * **Escape D** - Erases all characters from the cursor to the end of the word.
 * **Ctrl-U or Ctrl-X** - Erases al characters from the cursor back to the beginning of the command line.
 * **Ctrl-W** - Erases the word to the left of the cursor.
 * **Ctrl-A** - Moves the cursor to the beginning of the line.
 * **Left Arrow or Ctrl-B** - Moves the cursor one character to the left.
 * **Escape B** - Moves the cursor back one word to the left.
 * **Escape F** - Moves the cursor forward one word to the right.
 * **Right Arrow or Ctrl-F** - Moves the cursor one character to the right.
 * **Ctrl-E** - Moves the cursor to the end of command line.
 * **Up Arrow or Ctrl-P** - Recalls a command in the history buffer, beginning with the most recent commands.
 * **Ctrl-R or Ctrl-I or Ctrl-L** - Redisplays the system prompt and command line after a console message is received.

__**At the '--More-' prompt:**__
 * **Enter key** - Displays the next line.
 * **Space Bar** - Displays the next screen.
 * **Any alphanumeric key** - Returns to the EXEC prompt.

//Note:// //Control keys - Press and hold the Ctrl key and then press the specified letter key.// //Escape sequences - Press and release the Escape key, and then press the letter key.//
 * __Break keys:__**
 * **Ctrl-C** - When in any configuration mode, ends the configuration mode and returns to privileged EXEC mode. When in setup mode, goes back to the command prompt.
 * **Ctrl-Z** - When in any configuration mode, ends the configuration mode and returns to privileged EXEC mode.
 * **Ctrl-Shift-6** - All-purpose break sequence. Stops DNS lookups, trace routes, pings.

__**User EXEC Mode**__
 * **enable** - Enter Privileged EXEC mode

__**Privileged EXEC Mode**__
 * **copy running-config startup-config** - Copy the active configuration to NVRAM.
 * **copy startup-config running-config** - Copy the configuration in NVRAM to RAM.
 * **erase startup-configuration** - Erase the configuration located in NVRAM.
 * **ping ip_address** - Ping to that address.
 * **tracerouteip_address** - Trace each hop to that address.
 * **show interfaces** - Display statistics for all interfaces on a device.
 * **show clock** - Show the time set in the router.
 * **show version** - Display currently loaded IOS version, hardware, and device information.
 * **show arp** - Display the ARP table of the device.
 * **show startup-config** - Display the saved configuration located in NVRAM.
 * **show running-config** - Display the contents of the currently running configuration file.
 * **show ip interface** - Display IP statistics for interface(s) on a router.
 * **configure terminal** - Enter terminal configuration mode.
 * **show ip interface** - Display IP statistics for interface(s) on a router.
 * **configure terminal** - Enter terminal configuration mode.

__**Terminal Configuration Mode**__
 * **hostname //hostname//** - Assign a host name to device.
 * **enable password //password//** - Set an unencrypted enable password.
 * **enable secret password** - Set a strongly encrypted enable password.
 * **service password-encryption** - Encrypt display of all passwords except secret.
 * **banner motd# message #** - Sets a message-of-the-day banner.
 * **line console 0** - Enter console line configuration mode.
 * **line vty 0 4** - Enter virtual terminal (Telnet) line configuration mode.
 * **interface Interface_name** - Enter interface configuration mode.


 * __Line Configuration Mode__**
 * **login** - Enable password checking at login.
 * **password //password//** - Set line password.


 * __Interface Configuration Mode__**
 * **ip address //ip_address netmask//** - Set interface IP address and subnet mask.
 * **description //description//** - Set interface description.
 * **clock rate value** - Set clock rate for DCE device.
 * **no shutdown** - Set interface to up.
 * **shutdown** - Administratively set interface to down.

**ROM** = IOS (Scaled Down) / Bootstrap / Diagnostic SW **Flash** = IOS (Full Version) **NVRAM** = Start-up Config **RAM** = Running Config


 * __ How to clear any existing configuration __**
 * Router# erase startup-config** = clears the startup config
 * Router# reload** = restarts the router



When configuring a router, certain basic tasks are performed including:
 * Naming the router
 * Setting passwords
 * Configuring interfaces
 * Configuring a banner
 * Saving changes on a router
 * Verifying basic configuration and router operations