Recovering the root Password in AIX

Answer

CONTENTS:

  INTRODUCTION
  SCOPE
  BOOTING YOUR SYSTEM INTO SERVICE MODE
  RECOVERING THE ROOT PASSWORD

INTRODUCTION

This TechNote looks at how to reset/recover the root password when it has been forgotten/misplaced.

SCOPE

Applicable to all versions of AIX.

BOOTING YOUR SYSTEM INTO SERVICE MODE

If your sysytem uses an Hardware Management Console (HMC), please see the following technote to boot into Service/Maintenence Mode…

https://www.ibm.com/support/pages/node/720545

If your system is a microchannel system do the following to boot it into Service Mode:

Turn the key to the Maintenance position and press the yellow Reset button twice. You must boot from bootable media, such as an installation CD-ROM, installation tape or a bootable backup tape made via the mksysb command or the Sysback product of the correct level for this machine

If your systems is a PCI-based system do the following to boot it into Service Mode:

When booting a PowerPC into Service mode, cd0 or rmt0 must be before the hdisk in the bootlist. If not, change the bootlist at boot time. On some models, you can set the machine to use a default bootlist that includes both cd0 and rmt0. If a bootable CD or tape is in the CD-ROM or tape drive, the machine will boot from this device.

For most of the newer PCI-based models, selecting the default bootlist, with a bootable tape or CD loaded in the machine, causes the system to automatically boot from that device. Generally, the next menu on the screen asks the administrator to define the system console.

For all machines discussed here, if you are using a graphical terminal, you will use a function key such as F5. If you are using an ASCII terminal, use an equivalent number key such as 5. Use the numbers across the top of the keyboard, not the numbers on the numeric keypad. On ASCII terminals, the icons may not be displayed on the screen; the number can be pressed between the second and the third beeps, the second beep being a series of three clicks.

RECOVERING THE ROOT PASSWORD

Once the system is Service Mode and you've booted on the bootable media, which is of the same version and level as the system, follow the prompts to the Welcome to Base OS menu.

      1. Choose Start Maintenance Mode for System Recovery (Option 3).

      2. The next screen displays prompts for the Maintenance Menu

              Choose Option 1: Acess a Root Volume Group

      3. The next screen prints a warning message and asks you to select
         0 to continue.

              Select 0 to Continue

      4. The next screen asks you to select the proper volume group.

              Select the proper volume group for your machine.

      5. The console will display information about rootvg and a menu
         with two options.

              Choose option 1: Access this volume group and start a
                               shell

      6. Once you have the command prompt, run the passwd command:

              passwd
              Changing password for "root"
              root's New password:
              Enter the new password again:

      7. With the key in Normal position (if applicable), issue the
         reboot command:

              sync;sync;sync;reboot