System won’t boot. But I have an OK prompt

System won’t boot. But I have an OK prompt

1. Can you run the banner?
ok banner

2. Can the Machine boot from CDROM into Single User Mode?
#boot cdrom -s
– YES – but fails to boot to the boot disk, then there is a software problem with the OS on the boot disk.
– NO – then it is most likely a Hardware Problem.

a. Verify that the boot cd is a supported OS for this system.
b. Try to boot the exact same OS CD as is loaded on the boot disk.

3. Have any changes been made to the system since it last booted correctly?
– Patches applied, Packages added, Hardware installed or removed

4. Are you getting past the banner and ok prompt?

5. Can you see your boot device from the ok prompt?
ok setenv auto-boot? false
ok reset
ok probe-scsi-all
ok probe-ide-all

6. Are you attempting to boot from your default boot device?
ok printenv boot-device
ok devalias {output from previous command}
ok boot -v
– Now just watch to make sure that the output from the devalias command matches the device that the system is attempting to boot from.

7. Is the system automatically attempting to boot from your diag device (net by default)?
ok printenv diag-device
ok setenv diag-switch? false


A. If the diag-switch OBP variable is set to true, then the machine will attempt to boot from the diag-device which is usually different from the default boot device. Set the diag-switch to false.

B. If the system hangs at the "twirly bird" ( | / – \ ) or the configuring devices statement, then there may be hardware on the system that is not recognized or is failed.

C. If the system comes up and stops at the maintenance prompt (press control-d for normal start-up or enter root password for system maintenance) the files systems need to be fsck’ed. Enter the root password and fsck the filesystems.

Enter Root Password: ******
#fsck -y /dev/rdsk/cXtXdXsX

D. If the root drive is encapsulated or under control of a volume management utility, then the issue needs to be handled as a storage issue.

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