Cisco Cisco IPS 4255 Sensor

For 4200 series appliances, the password recovery is found in the GRUB menu, which appears during 
bootup. When the GRUB menu appears, press any key to pause the boot process. 

You must have a terminal server or direct serial connection to the appliance to use the GRUB menu to 
recover the password. 

To recover the password on appliances, follow these steps:

Reboot the appliance.

The following menu appears:

GNU GRUB version 0.94 (632K lower / 523264K upper memory)

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0: Cisco IPS

1: Cisco IPS Recovery

2: Cisco IPS Clear Password (cisco)

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    Use the ^ and v keys to select which entry is highlighted.

    Press enter to boot the selected OS, 'e' to edit the

    Commands before booting, or 'c' for a command-line.

    Highlighted entry is 0:

Press any key to pause the boot process.

Choose 

.

The password is reset to cisco. You can change the password the next time you log in to the CLI.

For the procedure for connecting the appliance to a terminal server, refer to 

For the IPS 4240 and IPS 4255 you can use the ROMMON to recover the password. To access the 
ROMMON CLI, reboot the sensor from a terminal server or direct connection and interrupt the boot 
process.

To recover the password using the ROMMON CLI, follow these steps:

Reboot the appliance.

To interrupt the boot process, press ESC or Control-R (terminal server) or send a BREAK command 
(direct connection).

The boot code either pauses for 10 seconds or displays something similar to one of the following:

Evaluating boot options

Use BREAK or ESC to interrupt boot