Friday, December 10, 2010

Password recovery on a Catalyst switch

Part of the preparation work for my home lab is to clear off the old config on the recycled systems. This includes performing a password reset.

The steps on my catalyst switches are as follows:

  1. Access ROMMON - power off the device, press the Mode button on the front, connect the power. When the 'x1' LED goes out release the Mode button and ROMMON will be presented in your terminal
  2. Enable Flash - ROMMON: flash_int
  3. Enter the Following cmd - :loader_helper
  4. Check the directory structure - : dir flash:
  5. Rename the Startup-config file - :rename flash:config.text flash:config.bak
  6. Restart the system - :boot
  7. At the prompt enter 'no', you do not wish to run through the automation steps
  8. At this point you can either stop here and run the system as a fresh system or you can continue
  9. Rename the config.old back to config.text - switch#rename flash:config.bak flash:config.text
  10. Next, load the config file in the memory - switch#copy flash:config.text system:running-config
  11. At this point you are now running your original config. All you need to do now is reset all your access passwords
  12. Change the Enable Secret - switch(config)#enable secret [Secret]
  13. Change the Enable Password - switch(config)#enable password [Password]
  14. Change the Telnet password - switch(config)#line vty 0 4; switch(config-line)#password [Password] 
  15. Set the VTY line to prompt for the password - switch(config-line)#login
  16. Finally, save your running-config - switch#wr mem

How to access ROMMON

In your working environment how often do you really need to access ROMMON? if everything is in order and you have up to date documentation then I suspect not very often.

So, I come to preparing my new home lab for my CCNP SWITCH course and I've had to remove the old configuration off the recycled kit.

For my access server I'm going to run an old 2610 router, not the most feature rich router but it has a single ethernet interface which I run inter-VLAN routing off. I have 2 catalyst 3550's for my distribution layer and I have 2 Catalyst 2950's for the access layer.

Accessing ROMMON.
Accessing ROMMON is actually very simple on the catalyst switches. Power off your device. Hold the mode button down on the front of the box, then connect the power lead.

Wait for the 'x1' interface indicator to go out and then release the mode button.

For the 2610 you power cycle the system and at the point the boot process is displayed on screen you hit ctrl+Break.

Thursday, December 9, 2010

To 'Delete' or to 'Erase'?

When do you use the commands Delete or Erase?

Well it depends on what you are wanting to do.

If you want to remove a file, you use the delete cmd, for example:
R1#delete flash:config.old
SW1#delete vlan.dat

If you want to remove system information you use the erase cmd, for example:
R1#erase startup-config

If in doubt use the ? to inspect your options: