13. Reset lost root password

This section describes how to reset a forgotten or lost BMC root password.

If the firmware version is 1.9.0 or later, then you can recover the password by using the serial port (see Section 13.1, BMC command line). if firmware version is earlier than 1.9.0, you will need to perform a factory reset (see Section 13.2, Factory reset from U-Boot).

13.1. BMC command line

This procedure is only applicable with BMC firmware version 1.9.0 or later.

If you have forgotten the BMC root password then physical access to the IPU-Machine is required to reset it. You need to use a USB cable to connect the Micro-USB management port of the IPU-Machine to the management server (see Fig. 13.1).

_images/ipum_rear.png

Fig. 13.1 IPU-Machine rear side showing the location of the Micro-USB management port (green) indicated by “Mgt”

You can then reset the password by rebooting the machine and interrupting U-Boot from the serial console using, for example, minicom. Once in U-Boot, append rescue_bmc to the bootargs environment variable, and then boot:

ast# setenv bootargs console=ttyS4,115200n8 root=/dev/ram rw rescue_bmc
ast# boot

This will automatically log you in as the root user on the serial console. You can now change the root password by using the passwd command.

13.2. Factory reset from U-Boot

You can perform a factory reset from U-Boot, using the following steps:

  1. Gain physical access to the IPU-Machine and connect your laptop or server to the IPU-Machine management port with a Micro-USB cable (see Fig. 13.1).

  2. Start a serial communication program, for example minicom. The required settings are:

    • Baud rate: 115200

    • Data bits: 8

    • Stop bits: 1

    • Enable software flow control if using minicom. Set flow control to “none” if using putty.

  3. Do an AC power cycle by unplugging the AC cables from the power supplies. Let the system power down, and then reinsert the cables, while having the serial terminal running. When the BMC reboots, enter U-Boot by pressing any key.

  4. You will now see the ast# prompt. Enter the following commands:

    ast# setenv openbmconce factory-reset
ast# save
ast# save
ast# reset

  5. Factory reset will now be in progress. Once it is complete, let the BMC boot and log in with the default credentials.

  6. You can now change the root password by using the passwd command.