13.8. Error Analysis

13.8.1. Log Files

Unless otherwise specified, hotplug only sends a few important messages to syslog. To obtain more information, set variable HOTPLUG_DEBUG=yes. If you set this variable to the value max, every shell command will be logged for all hotplug scripts. This means that file /var/log/messages, in which syslog stores all the messages, will be correspondingly much larger. As syslog is not launched during the boot process until after hotplug and coldplug, it is possible, however, for the first messages not to be logged. If these messages are important to you, then you should specify a different log file via the variable HOTPLUG_SYSLOG. Further information on this topic is contained in /etc/sysconfig/hotplug.

13.8.2. Boot Problems

If a computer hangs during the boot process, you can disable hotplug or coldplug by entering NOHOTPLUG=yes or NOCOLDPLUG=yes, respectively, at the boot prompt. When the system is up and running, you can re-enable hotplug by entering the command rchotplug start.

To find out whether a particular module that is loaded by hotplug is responsible for the problems, enter HOTPLUG_TRACE=<N> at the boot prompt. The names of all the modules will be output one after another on the screen, until after N seconds they are actually loaded. You cannot intervene while this is going on.

13.8.3. The Event Recorder

The script /sbin/hotplugeventrecorder is called upon each event by /sbin/hotplug and sbin/hotplug-stopped. If a directory /events exists, then all hotplug events are stored as individual files in this directory.