HP-UX System Administrator's Guide: Configuration Management

Guidelines for Recovering from Errors
If you have an undesirable or unbootable kernel configuration, HP recommends the
following approach to resolving the problem.
• If your system is up:
— If you know which configuration change caused the problem:
◦ If your backup configuration hasn’t been updated since the bad change:
– Load the backup configuration with kconfig –l backup.
◦ Else (your backup configuration also has the problem in it):
– Try to reverse the change using kcmodule or kctune.
Always specify the –K option to preserve the backup configuration.
— Else (you don’t know what change caused the problem, or the above didn’t
work):
◦ Load a known good configuration using kconfig –l.
Try the backup configuration first.
• Else (your system is down):
— If you have had a hardware failure and now the system won’t boot or if you
need to preserve the bad configuration:
◦ Try booting in fail-safe mode (see above).
◦ Repair the configuration or the hardware, then reboot.
— Else (no hardware failure, no need to preserve bad configuration):
◦ Try booting a known good configuration, such as backup.
Of course, depending on the level of your support contract with HP, you can call on
HP field service personnel to perform these steps, if needed.
If you get to a point where you cannot boot any of your saved configurations, even in
fail-safe mode, your last resort is to boot from the HP-UX installation media. If that
succeeds, you do not necessarily have to reinstall HP-UX; you can open a shell and try
to repair your system.
Kernel Configuration Example
In this example, the system administrator, Susan, is setting up a new HP-UX system
to run a database server called Prophet. It has just finished booting after the initial
install.
GenericSysName [HP Release B.11.31] (see /etc/issue)
Console Login: root
Password:
...
WARNING: YOU ARE SUPERUSER !!
Kernel Configuration Example 201