Cisco IOS Initial Configuration

Cisco IOS  Initial configuration is most important part for beginners, without understanding initial configuration and CLI modes correctly beginners will stuck. In this section scribe about basic Switch configure,

1) Time and date
2) Switch hostname
3) Privilege mode password
4) Console password
5) VTY (Telnet login password)
6) Service password encryption 
7) Remote management (management ip address)
8) IP default-gateway
9) Save configuration

Switch>
Switch>enable
Switch#clock set ?  ( if problem with some command, Type ? mark hit Enter key, hahaha Cisco IOS make me  happy :) that's why Cisco IOS fame )
  hh:mm:ss  Current Time
Switch#clock set 17:43:00 ?
   <1-31>  Day of the month
   MONTH   Month of the year
Switch#clock set  17:43:00 june ?
  <1-31>  Day of the month
Switch#clock set  17:43:00 june 8 ?
  <1993-2035>  Year
Switch#clock set  17:43:00 june 8 2012  
Switch#
Switch#configure terminal
Switch(config)#hostname SW1
SW1(config)# !configure privilege mode password type enable password your-password
SW1(config)#enable password madusanka
SW1(config)#line console 0         (entering  line console sub configuration mode )
SW1(config-line)# exec-timeout 0 0   ( first 0 minute and second 0 mean  second's, both 0 mean never time out)
SW1(config-line)#password  madusanka  (In my case password is madusanka)
SW1(config-line)# login  (enable console login)
SW1(config-line)#exit
 SW1(config)#
 SW1(config)#
SW1(config)#line vty ?
  <0-15>  First Line number
SW1(config)#line vty 0 ?
  <1-15>  Last Line number
  <cr>
SW1(config)#line vty 0 4    (if you type 0 - 15   that mean can 16 telnet session to switch )
SW1(config-line)#exec-timeout 0 0   (never timeout)
SW1(config-line)#password madusanka
SW1(config-line)#login
SW1(config-line)#exit
SW1(config)#
SW1(config)# do show running-config

 !
hostname SW1
!
enable password cisco
!

!
line con 0
 password cisco
 login
 exec-timeout 0 0
!
line vty 0 4
 exec-timeout 0 0
 password madusanka
 login

SW1(config)#!my god that you see, my all password show in clear text, so how to fix that, get ready!
SW1(config)#service password-encryption  (this command make my clean text password to MD7 encryption )
SW1(config)#do show running-config

!
hostname SW1
!
enable password 7 0822455D0A16      <--- see it  ?
!
!

 line con 0
 password 7 0822455D0A16               <--- see it  ?
 login
 exec-timeout 0 0
!
line vty 0 4
 exec-timeout 0 0
 password 7 082C4D4A1C0A0419190A             <--- see it  ?
 login

SW1(config)#


What is a Remote Management ? In simply manege via SSH  or telnet without connecting console cable, yes that's wright,

SW1(config)# inteface  vlan 1 192.168.1.50 255.255.255.0  (management interface )
SW1(config-if)# ip  address  192.168.1.50 255.255.255.0    (management ip address )
SW1(config-if)# no shutdown                            ( Interface activate command)
%LINK-5-CHANGED: Interface Vlan1, changed state to up 
SW1(config-if)#exit
SW1(config)#ip default-gateway 192.168.1.1  ( where the exit )
SW1(config)#exit
SW1#
SW1#! Almost finish our basic configuration,  final step is save current running-configuration to NVRAM

, type   copy running-config startup-config in privilage mode, and any other place you can used do write

SW1#copy running-config startup-config
Destination filename [startup-config]?
Building configuration...
[OK]
SW1#
SW1# !#######################END#########################

CISCO IOS CLI and command modes

The Cisco IOS command line interface (CLI) is a text-based program that enables
 the entering and executing of Cisco IOS commands to configure, monitor, and maintain Cisco devices.
Almost All  CISCO device use similar CLI,  When the router has completed the power on sequence, and the Router> command appears, that Initial mode of  All the CISCO Device, that we call User Exec mode,
Now CLI can used IOS command,  this mode used to enter privilege mode, monitoring some status, network connectivity(ping, traceroute), lets move to next Mode by typing  enable and hit enter.

Router>enable

Router# !wellcome to Privilege Exec mode, many command available used such as Monitoring, debugging, configuring, configuration saving, and much more.  type configure terminal or conf  t  goto gobble configuration mode
Router#conf t 
Router(config)#!this is a primary Configuration mode, Almost 99.99% Command for a configuration, 
Router(config)#!Other modes are sub-configuration, 
Router(config-if)# ! Interface configuration,
Router(config-router)# !Router configuration,
Router(config-line)# !  terminal line confuguration,
basically i have discussed about 4 CLI modes, those are User Exec, privilege mode, gobble configuration,
and Sub-config mode as below image.

What exactly Cisco organization do ?

Cisco is massive company they offer network priority product, software, services, certification  and much more...

1) Their primary product's is Routers and Switches,
other products is Firewall system, VoIP system,  Video conferencing equipment, .....

2) Cisco every routers and switch's running IOS (originally Internet Operating System), they had more people writing software. most of the software was for their own proprietary products

3) I am not talking about what services they have.

4) Cool topic is Cisco priority Certification program,
Cisco certification path as bottom image