Resolving "No OS image detected" Boot Hang

Answer

Probable causes and solutions to this situation

First, press CTRL-C to stop the system from attempting to boot.

You will see the system enter the IBM splash screen with choices to boot into SMS, Open Firmware or using the default or stored boot list.

As you see the choices across the screen press 1 to enter SMS :

IBM IBM IBM IBM IBM IBM IBM IBM IBM IBM IBM IBM IBM IBM IBM IBM IBM IBM

1 = SMS Menu 5 = Default Boot List
8 = Open Firmware Prompt 6 = Stored Boot List

Memory Keyboard Network SCSI Speaker


Bad bootlist or bad device in bootlist
We can check the current bootlist and set a new one if necessary from SMS.

PowerPC Firmware
Version AM780_068
SMS 1.7 (c) Copyright IBM Corp. 2000,2008 All rights reserved.
-------------------------------------------------------------------------------
Main Menu
1. Select Language
2. Setup Remote IPL (Initial Program Load)
3. Change SCSI Settings
4. Select Console
5. Select Boot Options

In the SMS menu choose 5

Then on subsequent screen choose:
2. Configure Boot Device Order


Configure Boot Device Order
1. Select 1st Boot Device
2. Select 2nd Boot Device
3. Select 3rd Boot Device
4. Select 4th Boot Device
5. Select 5th Boot Device
6. Display Current Setting
7. Restore Default Setting

To see the current bootlist setting choose 6. The system will probe the attached busses for the items in the boot list.

In this example below we see that either the boot list was cleared, was set to a disk that was not bootable (has no hd5 boot partition), or was not available to the system.

Current Boot Sequence
1. Device is not bootable or removed.
2. Device is not bootable or removed.
3. Device is not bootable or removed.
4. Device is not bootable or removed.
5. None

Press <ESC> to go back to the previous menu "Configure Boot Device Order"
Press 1 to set the first boot device

Select Device Type
1. Diskette
2. Tape
3. CD/DVD
4. IDE
5. Hard Drive
6. Network
7. None
8. List All Devices

Pick 5 to select Hard Drive.
Select Media Type
1. SCSI
2. SSA
3. SAN
4. SAS
5. SATA
6. USB
7. IDE
8. ISA
9. None
10. List All Devices

Select the Media Type (i.e. bus type) and you will be presented with choices for all adapters of that type. When an adapter is chosen SMS will probe the adapter for bootable devices.

If you don't know what type the boot disk is, you can select 10 List All Devices.

After this you will see a list of possible bootable devices:

Select Device
Device Current Device
Number Position Name
1. - Interpartition Logical LAN
( loc=U9117.MMD.067A967-V5-C22-T1 )
2. 1 SCSI 9 GB Harddisk, part=2 (AIX 7.1.0)
( loc=U9117.MMD.067A967-V5-C20-T1-L8100000000000000 )
3. 2 SCSI 9 GB Harddisk, part=2 (AIX 7.1.0)
( loc=U9117.MMD.067A967-V5-C21-T1-L8100000000000000 )
4. - SCSI CD-ROM
( loc=U9117.MMD.067A967-V5-C21-T1-L8200000000000000 )
5. None

Selecting one of these allows you to set it as a boot device or print more information on it.

SCSI 9 GB Harddisk, part=2 (AIX 7.1.0)
( loc=U9117.MMD.067A967-V5-C20-T1-L8100000000000000 )

1. Information
2. Set Boot Sequence: Configure as 1st Boot Device

Option 1 will give you a screen like this:

Device Information
/vdevice/v-scsi@30000014/disk@8100000000000000
: (Bootable)
DEVICE : SCSI 9 GB Harddisk, part=2 (AIX 7.1.0)
( loc=U9117.MMD.067A967-V5-C20-T1-L8100000000000000 )
NAME : disk
DEVICE-TYPE : block

Parent Information
IBM,FW-ADAPTER-NAME: Virtual SCSI
NAME : v-scsi
DEVICE-TYPE : vscsi

Use option 2 to set the device as the first bootable device in the list.

Current Boot Sequence
1. SCSI 9 GB Harddisk, part=2 (AIX 7.1.0)
( loc=U9117.MMD.067A967-V5-C20-T1-L8100000000000000 )
2. Device is not bootable or removed.
3. Device is not bootable or removed.
4. Device is not bootable or removed.

Once a boot device is set, you may exit SMS and boot the server.

X = eXit System Management Services

Are you sure you want to exit System Management Services?
1. Yes
2. No

Type 1 and hit enter

You will see the banner

IBM IBM IBM IBM IBM IBM STARTING SOFTWARE IBM IBM IBM IBM IBM IBM
IBM IBM IBM IBM IBM IBM PLEASE WAIT... IBM IBM IBM IBM IBM IBM

Then "Welcome to AIX" as the kernel and boot image loads into RAM.

-------------------------------------------------------------------------------
Welcome to AIX.
boot image timestamp: 17:42:02 05/11/2016
The current time and date: 17:28:36 05/12/2016
processor count: 1; memory size: 3072MB; kernel size: 36351631
boot device: /vdevice/v-scsi@30000014/disk@8100000000000000
-------------------------------------------------------------------------------

After this the system should continue to boot up to multiuser.


Bad disk in rootvg
Boot into Maintenance Mode with rootvg filesystems mounted, run checks on the rootvg disks:
# lquerypv -h /dev/hdiskX
# lqueryvg -Atp /dev/hdiskX
# lsvg -p rootvg

If a disk is marked missing or it is determined to be bad, find out if rootvg is mirrored between it and another disk:

# lsvg -l rootvg
If it is mirrored you will see 2 PPs for every LP

# lsvg -l rootvg
rootvg:
LV NAME TYPE LPs PPs PVs LV STATE MOUNT POINT
hd5 boot 2 4 2 closed/syncd N/A
...

Then remove the mirror from the bad disk.

# /etc/methods/cfg64
# unmirrorvg rootvg hdiskX

Make sure no unmirrored lvs are left on the bad disk
# lspv -l hdiskX

If the disk is still missing using migratepv to move the logical volumes will not be possible

0516-817 migratepv: Source physical volume hdisk1 state does not
allow migration.

You will need to remove the logical volume with rmlv (or filesystem with rmfs) to be able to reduce out the disk. Then the logical volume / filesystem will need to be created later and the data in it restored.


Corrupt or missing hd5 partition
If there is no boot partition (hd5) boot into maintenance mode with filesystems mounted and recreate it.

# mklv -y hd5 -t boot -ae rootvg 1 hdiskX

or if rootvg is mirrored
# mklv -y hd5 -t boot -ae -c2 rootvg 1 hdiskX hdiskY

Then rewrite the boot image:
# bosboot -ad /dev/hdiskX

If mirrored write one out to the other disk also
# bosboot -ad /dev/hdiskY

Set the bootlist
# bootlist -m normal hdiskX hdiskY


Bad ODM files
Boot into maintenance mode with filesystems mounted. If bosboot or other commands show ODM errors replace the ODM from boot media.

# bosboot -ad /dev/hdisk20
0518-507 odmget: Could not retrieve object for CuAt, ODM error number 5904
0301-162 bosboot: savebase failed with /dev/hdisk20.
0301-165 bosboot: WARNING! bosboot failed - do not attempt to boot device.

# bootlist -v -m normal hdisk20
'ibm,max-boot-devices' = 0x5
match_specific_info: ut=disk/fcp/NetAppMPIO
0514-221 bootlist: Unable to make boot device list for hdisk20

Boot into maintenance mode with filesystems mounted. If bosboot or other commands show ODM errors it's possible the ODM is corrupt.

Reboot into maintenance mode again, this time start a shell before mounting filesystems. Save a copy of the old ODM files and replace them with ones from boot media.

# mount /dev/hd4 /mnt
# mount /dev/hd2 /mnt/usr
# mkdir /mnt/etc/objrepos/bak
# cp /mnt/etc/objrepos/Cu* /mnt/etc/objrepos/bak
# cp /etc/objrepos/Cu* /mnt/etc/objrepos
# umount /dev/hd2
# umount /dev/hd4
# exit