Blow Away Your Cisco Catalyst Configuration

Posted on in Networking

If you've ever needed to reset a Cisco Catalyst switch to it's factory default (locked out, perhaps?), you've probably spent some time digging around on Cisco's web site. The Catalyst password recovery procedure starts off by reseting the Catalyst to it's original factory settings. Below, I'm going to give you a quick run-down of what you need to know out of that document. I'll assume that you already have the a serial cable connected to the device and you're staring at a Password: prompt.

  1. Power off the switch, hold down the Mode button, and power the switch back on. How long you have to hold down the Mode button depends on the model of Catalyst you're using. For reference, I've included the table from the Cisco documentation as Table 1 below. The switch should now be at a switch: prompt.
  2. flash_init The flash_init command initializes the flash. There will be some scrolling text as the switch tells you what it's doing, but it should end at the switch: prompt.
  3. load_helper This command has no output and returns you immediately to the switch: prompt.
  4. rename flash:config.text flash:config.old This will save the startup-config so that you can use it later. When the switch boots, it will be back to factory default. It should return you to the switch: prompt.
  5. boot This will load IOS and should end at the System Configuration Dialog.

At this point, you can either reconfigure the switch from scratch, or use the saved configuration to reset the password.

Catalyst Switch Series LED Behavior and Mode Button Release Action


2900XL, 3500XL, 3550 Release the Mode button when the LED above Port1x goes out.
2940, 2950 Release the Mode button after approximately 5 seconds when the Status (STAT) LED goes out. When you release the Mode button, the SYST LED blinks amber.
2960, 2970 Release the Mode button when the SYST LED blinks amber and then turns solid green. When you release the Mode button, the SYST LED blinks green.
3560, 3750 Release the Mode button after approximately 15 seconds when the SYST LED turns solid green. When you release the Mode button, the SYST LED blinks green.

Table 1. Catalyst Switches and the Mode button

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