Booting in Service Mode


About This Document
    Related Documentation
Booting Microchannel Systems into Service Mode
Booting PCI-Based Systems into Service Mode
PCI Machine-Specific Information
Accessing rootvg and Mounting File Systems

About This Document

This document discusses the process by which an RS/6000 system can be booted into service mode (also known as maintenance mode) to install the machine, restore an operating system backup, or perform maintenance on the rootvg volume group.

The information in this document applies to AIX Versions 3.x and 4.x.

Related Documentation

For more in-depth coverage of this subject, the following IBM publication is recommended:

IBM documentation can also be accessed online through the following URL:

Similar documents can be accessed through the following URL:

Booting Microchannel Systems into Service Mode

To boot microchannel systems 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.

For AIX Version 3.2, you may use bootable bosboot diskettes. To boot from these, insert the first (bosboot) diskette into the diskette drive. When you see LED c07, insert the next diskette, which is usually the display extensions diskette. After this diskette is read, you should receive a menu prompting you for the installation diskette.

For information on accessing your rootvg volume group, see the section entitled "Accessing rootvg and Mounting File Systems".

All of the preceding discussion assumes that the service mode bootlist has not been modified from the default bootlist. If so, it needs to be reset such that one of the boot media types from the preceding selections is before the standard boot media, such as the hard disk.

If the machine is an SMP model (7012-Gxx, 7013-Jxx, and 7015-Rxx) and the Autoservice IPL flag is disabled, then a menu like the following will display when it is booting in service mode:

                         MAINTENANCE MENU (Rev. 04.03)
                       0> DISPLAY CONFIGURATION
                       1> DISPLAY BUMP ERROR LOG
                       2> ENABLE SERVICE CONSOLE
                       3> DISABLE SERVICE CONSOLE
                       4> RESET
                       5> POWER OFF
                       6> SYSTEM BOOT
                       7> OFF-LINE TESTS
                       8> SET PARAMETERS
                       9> SET NATIONAL LANGUAGE

Choose the SYSTEM BOOT option and then select the BOOT FROM LIST option from the subsequent menu.

Booting PCI-Based Systems into Service Mode

When booting an RS/6000 PowerPC system into service mode, you must either have cd0 or rmt0 in the bootlist before your hdisk, or 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 Sr 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.

Note that for all machines discussed here, if you are using a graphical terminal, you will use a function key, such as F2. If you are using an ASCII terminal, use an equivalent number key, such as 2 (the number 2 near the left side of the keyboard, not the 2 on the number pad). On ASCII terminals, the icons may not be displayed on the screen; the number can be pressed between the second and third beeps (the second beep being a series of 3 clicks).

PCI Machine-Specific Information

The following systems all use the F5 or 5 key to read from the default boot list, which is written into the system firmware:

MODEL       7017       7024       7025       7026       7043       7137
-------   -------    -------    -------    -------    -------    -------
TYPE      S70        E20        F30        H10        43P-140    F3L
          S7A        E30        F40        H50        43P-150        
                                F50        H70        43P-240           

On these machines, use 5 (on the keyboard, not the keypad) if you are using an ASCII terminal. On a locally attached graphics console, use the F5 function key. The F5 or 5 key must be pressed just after the keyboard icon or message is displayed on the console.

The following systems use the F1 key to enter System Management Mode (SMS):

MODEL       6040       7042       7247       7249
-------   -------    -------    -------    -------
TYPE        620        850        82x        860

You should be in an Easy-Setup menu. Select the Start Up menu. Clear the current bootlist settings and then select the CD-ROM for choice 1 and hdd (the hard disk) for choice 2. Select OK. Insert the CD-ROM and select the EXIT icon. The machine should now boot from the CD-ROM.

The following systems use the F2 key to enter SMS:

MODEL         6015       6050       6070       7020       7248
-------     -------    -------    -------    -------    -------
TYPE          440        830        850        40P        43P

Select Select Boot Device from the initial menu on the screen, and then select Restore Default Settings from the list. Press the Esc key to exit all the menus, and then reboot the machine. The system should boot from your bootable media.

For information on accessing your rootvg volume group, see the next section in this document.

Accessing rootvg and Mounting File Systems

For AIX Version 3, choose the limited function maintenance shell (Option 5 for AIX 3.1, Option 4 for AIX 3.2).

If you only have one disk on the system, then hdisk0 will be used in the execution of the getrootfs or /etc/continue commands, which follow. If you have more than one disk, determine which disk contains the boot logical volume in this manner:

AIX 3.2.4 or AIX 3.2.5:

Run getrootfs; the output will indicate which disk contains the hd5 logical volume.

AIX 3.1 to AIX 3.2.3e:

Run lqueryvg -Ltp hdisk# for each hdisk. You can obtain a listing of these with lsdev -Cc disk until you get output SIMILAR to:

             00005264feb3631c.2  hd5  1
If more than one disk contains this output, you can use any disk when running getrootfs.

Now, access the rootvg volume group by running one of the following commands, using the disk you obtained in the preceding step:

    AIX 3.1:                     /etc/continue hdisk#
    AIX 3.2.0-3.2.3e:            getrootfs -f hdisk#
    AIX 3.2.4-3.2.5:             getrootfs hdisk#

NOTE: If you want to leave the primary OS file systems (/, /usr, /tmp, and /var) unmounted after this command has completed (in order to run fsck, for instance), place a space and the letters sh after the hdisk in the preceding command. For example:

    getrootfs hdisk0 sh
For AIX Version 4, choose Start Maintenance Mode for System Recovery (option 3). The next screen will be called Maintenance; select option 1 (Access a Root Volume Group). At the next screen, type 0 to continue, and select the appropriate volume group by typing the number next to it. A screen like the following will display.


                           Access a Root Volume Group

Type the number for a volume group to display the logical volume information and press Enter.

  1)  Volume Group 0073656f2608e46a contains these disks:
      hdisk0  2063 04-C0-00-4,0

Once a volume group has been selected, information will be displayed about that volume group.


                           Volume Group Information
    Volume Group ID 0073656f2608e46a includes the following logical volumes:
         hd6         hd5         hd8         hd4         hd2      hd9var
         hd3         hd1        

Type the number of your choice and press Enter.

   1) Access this Volume Group and start a shell
   2) Access this Volume Group and start a shell before mounting filesystems
  99) Previous Menu

If the logical volumes listed do not include logical volumes like hd4, hd2, hd3, and so on, you may have selected the wrong volume group. You can hit 99 to back up one screen and select again.

Now you may select one of two options: Access this volume group and start a shell (Option 1), or Access this volume group and start a shell before mounting file systems (Option 2). Option 2 allows you to perform file system maintenance on /, /usr, /tmp, and /var before mounting them.

Errors from these steps may indicate failed or corrupt disks in rootvg. You should correct these problems. For additional assistance, contact your vendor, your local branch office, or your AIX support center.

Booting in Service Mode: boot.service.all.krn ITEM: FAX
Dated: 99/04/14~00:00 Category: krn
This HTML file was generated 99/06/24~12:41:54
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