CST3607 Class Notes 2018-10-18

Telnet, Console and AUX Port Passwords on Cisco Routers Configuration Example

  • The login command enables password checking at login.
  • If the login command isn’t applied, the console port won’t prompt for authentication.
  • For Cisco IOS v12.2 and newer, you cannot set the login command before a password is set on a line.
    • If you were able to “enable password checking at login,” but did not set a password, that line won’t be usable. You’ll get prompted for a password that doesn’t exist.
    • Cisco IOS prior to v12.2 did not have this “password” then “login” restriction.

Set password for console access:

(config)# line console 0
(config-line)# password <password_here>
(config-line)# login

Routers

Configuration Register Bits

  • default setting: 0x2102
  • 16 bits read 15-0, from left to right
Register2102
Bit Number15 14 13 1211 10 9 87 6 5 43 2 1 0
Binary0 0 1 00 0 0 10 0 0 00 0 1 0

To bypass startup-config, we’ll need to turn on bit 6 in the Configuration Register.

Register214
2
Bit Number15 14 13 1211 10 9 87 6 5 43 2 1 0
Binary0 0 1 00 0 0 10 1 0 00 0 1 0
  • Working with Configuration Files
  • Cisco IOS: Configuration Register & Password Reset
    • Using Cisco 2600 & 2800 series routersConnecting to a router using the console/rollover cable and HyperTerminalGetting into ROM monitor modeChanging the configuration register to turn on bit 6Setting an encrypted password

Lab-01

You must be in this class to get credit for this lab.

  • Lab-01 (part 1 of 2): Download and Install: LammleSim – IOS CCNA RS Simulator
    • Boot into the Windows Server partition for our class
    • Download and install LammleSim into the Windows Server.
  • Lab-01 (part 2 of 2): Connecting to a switch or router via the console port
    • Default serial port settings are 9600,n,8,1,none
    • Explore/query the device using the diagnostic Cisco IOS commands.

Read / Do

  • CCNA Routing and Switching Study Guide, 2nd Edition: Chapter 7 (Cisco IOS)
    • Do the Chapter 6 and Chapter 7: Written Lab, Review Questions, and Hands-on Labs
  • Bring in your book (Chapter 6 and Chapter 7) for Hands-on lab’s.
  • Cisco IOS and Router Command Reference

Note: Until further notice, bring your text book to every class, so that you’ll have access to the instructions for the Hands-on Labs.

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