On Debian-based distributions, such as Ubuntu, you can install Hudson through
apt-get. See http://jenkins-ci.org/debian/ for the instruction. Recent versions are available in an experimental apt repository , please see this post for further details. Note that you need the package daemon using sudo apt-get install daemon.
/etc/init.d/hudsonfor more details.
/var/log/hudson/hudson.log. Check this file if you are troubleshooting Hudson.