Read the man page for syslog.conf - it is VERY informative.
Quote:
facility.level /..../hardware.log
The problem is: what to put in the facility field (kern?, daemon? or something else).
Another problem is: once the configuration file has been modified, do i have to restart the syslogd daemon in order to have my modification taken into account?
The last question is: once the hardware related system messages will be logged in the file "hardware.log" what will they look like?
Try kern.warning for the facility.level. Most hardware errors should be seen with this (realize you may still get errors that you don't see - from all the questions you have been asking about syslog and hardware errors, you have some of the other tools available that you need).
Yes, changes to the syslog.conf require you to send a hup signal to the daemon - just find the pid and use the following command replacing xxx with the pid
# kill -HUP xxx
What will the messages look like - hard to say. Each should have the following format:
date time hostname tag[pid]: message