Managing Systems and Workgroups: A Guide for HP-UX System Administrators

Configuring a System
Reconfiguring the Kernel (HP-UX 11i Version 2)
Chapter 3324
Persistence of Changes
By default, the kernel configuration tools will apply configuration
changes to the currently running system, causing an immediate change
in behavior. System administrators can override this default by
specifying the -h (hold) option to any of the commands. This option
causes the changes to be held until the system is rebooted. HP
recommends that this option be used only when the next reboot is
expected to happen soon. If the reboot doesn't happen for months after
the change, the change could come as an unwelcome surprise to an
administrator who had forgotten the request.
Some configuration changes cannot be applied without a reboot. These
changes will be held until the system is rebooted even if the –h option is
not specified. In these cases, a warning message will be printed.
If multiple configuration changes are requested in a single invocation of
one of the kernel configuration commands, and any one of those changes
requires a reboot, all of the requested changes will be held until the
system is rebooted. In particular, if a saved kernel configuration is loaded
using kconfig –l (load), and that configuration cannot be used without
a reboot, the state of the running system is not changed and the specified
kernel configuration will be used at next boot instead.
Changes being held for next boot can be listed using the -D (Differences)
option on the kcmodule, kctune, or kconfig commands. See the
following sections for more details on each of these commands.
Changes being held for next boot are discarded when the currently
running configuration is replaced using kconfig –i (import), kconfig
–l (load), or kconfig –n (next boot); when explicitly discarded using
kconfig –H (unHold); or when subsequent changes are made that
override them. For example, if you run.
# kctune –h nproc=5000 set to 5000, hold for next boot
# kctune nproc=6000 set to 6000, now
the value of nproc at next boot will be 6000. The change to 5000 is
discarded. A warning will be printed in these situations.
Changes that are made to the currently running system are retained
when the system is rebooted. They remain in effect until changed.