CISCO
  • CISCO CERTIFICATIONS
  • CISCO DevNet - Coding & API's
    • Untitled
  • CCNA
    • Networking Fundamentals
    • Introduction
    • OSI, TCP/IP and 5 Layer Model
    • Binary
    • Hexadecimal
    • Cabling and Packet Flows
    • IP v4 Addressing
      • VLSM
    • Cisco IOS Software
    • Wireshark Basics
    • Switches
      • VLANS
        • DTP/VTP (Cisco Proprietary)
        • STP - Classic
        • STP - RSTP
      • EtherChannel
    • Routing
      • Dynamic Routing
      • RIP and EIGRP
      • OSPF 1 - Basics
      • OSPF 2 - Cost, Neighbours and Configs
      • OSPF 3 - Network and LSA Types
      • FHRP
        • HSRP
        • VRRP
      • IP SLA
      • BGP
        • Regular Expressions
    • Programming
  • CCNP
    • SetUp Stuff
    • CCNP ENCOR 350-401
      • Packet Forwarding:
  • IP Address Managers
    • Opensource
  • CCNA LABS
  • CCNA LABS
Powered by GitBook
On this page
  • Informational
  • Modes
  • Useful Shortcuts
  • Managing Cisco IOS Configuration
  • Storing Files in Flash
  • Terminal Length & No IP Domain Lookup
  • Basic Device Security
  • LAB

Was this helpful?

  1. CCNA

Cisco IOS Software

Connection to a router, boot-up an various options including basic IOS commands, modes (user mode / privilege mode) etc

Informational

  • Console cable is a "roll over" cable. The pin-outs are 'rolled over'

    • Pin 1 --> Pin 8

    • Pin 2 --> Pin 7

    • Pin 3 --> Pin 6

    • Pin 4 --> Pin 5

    • Pin 5 --> Pin 4

    • Pin 6 --> Pin 3

    • Pin 7 --> Pin 2

    • Pin 8 --> Pin 1

  • Terminal Emulation

    • Hyper-terminal - Limited (Comes with Windows)

    • Putty - only runs on Windows

    • Terra Term - Free

    • SecureCRT - Windows and MacOS

    • iTerm

    • Royal TSX

Modes

  • User Mode: Router>

    • view only mode

    • limited set of commands

    • basic monitoring commands

  • Privilege Mode (Enable Mode): Router#

    • allows a lot more show commands

    • allow debugging

    • used to configure the device

  • Global Config Mode: Router#(config)

    • change global parameters

    • MOTD (message of the day) - should be a legal entity. You can use any delimiter like hash (#) , a letter like 'c' etc and have to end with the same delimiter.

  • Line Mode - remember to use the 'login' parameter to use the password feature

    • console (console)

    • vty 0 4 (Used for telnet and ssh access)

      • login

      • password cisco

      • input transport telnet ssh

Useful Shortcuts

  • Other useful commands

    • Ctrl-U = deletes an entire line

    • Ctrl-C = cancels the command

    • Ctrl+Shift 6 x = breaks a command (like issue with domain lookup - arrgghhhhhhhhh)

Managing Cisco IOS Configuration

  • Running Config and Startup Config

    • copy run start (from RAM to NVRAM - overwrites the NVRAM config)

    • copy start run (merges the NVRAM with the RAM config)

  • show start run | b vty ---- b = begin

    • line vty 0 4

    • login

    • !

    • end

  • #config replace nvram:startup (replaces the config)

  • #erase startup-config

  • #copy run tftp://192.168.1.1/<config_name>

    • copy run tftp to copy start tftp = override or replacement

    • copy tftp to running config = merge

    • copy tftp replace = will replace the configuration file

Storing Files in Flash

  • show flash

    • copy running-config flash:/run1.cfg

      • more flash:run1.cfg will show the contents of the config file

Terminal Length & No IP Domain Lookup

When you do a show run, by default the config is restricted to a certain amount of lines (24) and it will then give out the --more-- command and then press spacebar and the next 24 lines will show etc etc

A tip is to use the command # terminal length 0, which shows the ENTIRE config in one go (good if you have long configurations etc)

Another tip is to use #no ip domain lookup when the router takes a long time to time out after trying to resolve a mistake you typed into a domain name!!

Basic Device Security

  • (config)#service password encryption

    • not very secure as it encrypts enable password with a type 7

  • (config)#enable secret CISCO

    • will see a 5 (md5) in front of encrypted password.

If you have both "enable password" and "enable secret" configured - the IOS will only use the "enable secret" password and ignore the other

LAB

PreviousVLSMNextWireshark Basics

Last updated 4 years ago

Was this helpful?

Packet Tracer file