Unless otherwise specified, hotplug only sends a few
important messages to syslog. To obtain more
information, set the variable HOTPLUG_DEBUG
in the file /etc/sysconfig/hotplug
to
yes
. If
you set this variable to the value max
, every shell
command is logged for all hotplug scripts. This means that
/var/log/messages
in which syslog
stores all the messages becomes much larger. Because
syslog is launched during the boot process
after hotplug and coldplug, it is
possible, however, for the first messages not to be logged. If these
messages are important to you, specify a different log file
via the variable HOTPLUG_SYSLOG
.
Information about this topic is available in
/etc/sysconfig/hotplug
.
If a computer hangs during the boot process, disable
hotplug or coldplug by entering
NOHOTPLUG=yes
or
NOCOLDPLUG=yes
at the boot prompt. Due to
the deactivation
of hotplug, the kernel does not issue any hotplug events.
In the running system, you can activate hotplug by entering
the command
/etc/init.d/boot.hotplug start
.
All events generated up to that time are then issued and processed.
To reject the queued events, first enter
/bin/true
in
/proc/sys/kernel/hotplug
and reset the entry to /sbin/hotplug
after
some time. Because of the deactivation of coldplug,
the static configurations are not applied. To apply the
static configurations, later enter
/etc/init.d/boot.coldplug start
.
To find out whether a particular module loaded by
hotplug is responsible for the problem, enter
HOTPLUG_TRACE=<N> at the boot prompt. The names of
all the modules to load are then listed on the screen
before they are actually loaded after N
seconds. You cannot intervene while this is
going on.