Barking Iguana

Daemontools is a collection of tools that help keep manage processes. It's great for keeping daemons running - if they ever die then Daemontools just restarts them. Unfortunately the package for Ubuntu is a little broken because it relies on /etc/inittab and Ubuntu hasn't used this file for a long time. Here's how install Daemontools and fix the problem.

Installing Daemontools

This bit is easy.

sudo apt-get install daemontools

Daemontools is installed. Easy, huh? Unfortunately it won't start after a reboot. That's bad. The daemontools-run package was meant to make Daemontools start at system bootup but unfortunately it relies on a system that uses init... and Ubuntu doesn't. It uses upstart instead.

Make Daemontools run at system startup

Create the file /etc/event.d/svscanboot with the following content.

start on runlevel 2
start on runlevel 3
start on runlevel 4
start on runlevel 5

stop on runlevel 0
stop on runlevel 1
stop on runlevel 6

respawn
exec /usr/bin/svscanboot

You'll also need to mkdir /etc/service since this is where the Ubuntu-installed Daemontools looks for service definitions.

Now tell the system to start the process.

sudo initctl start svscanboot

Other distributions

Plenty of other distributions use upstart instead of init. Getting DaemonTools running on them is pretty similar.

• Fedora Core >= 9: http://directory.fedoraproject.org/wiki/Howto:Daemontools#Daemontools_Installation and http://qmail.jms1.net/daemontools/upstart.shtml