+h2. Configure the Docker cleaner
+
+The arvados-docker-cleaner program removes least recently used docker images as needed to keep disk usage below a configured limit.
+
+On Debian-based systems, install runit:
+
+<notextile>
+<pre><code>~$ <span class="userinput">sudo apt-get install runit</span>
+</code></pre>
+</notextile>
+
+On Red Hat-based systems, "install runit from source":http://smarden.org/runit/install.html or use an alternative daemon supervisor.
+
+Configure runit to run the image cleaner using a suitable quota for your compute nodes and workload:
+
+<notextile>
+<pre><code>~$ <span class="userinput">cd /etc/sv</span>
+/etc/sv$ <span class="userinput">sudo mkdir arvados-docker-cleaner; cd arvados-docker-cleaner</span>
+/etc/sv/arvados-docker-cleaner$ <span class="userinput">sudo mkdir log log/main</span>
+/etc/sv/arvados-docker-cleaner$ <span class="userinput">sudo sh -c 'cat >log/run' <<'EOF'
+#!/bin/sh
+exec svlogd -tt main
+EOF</span>
+/etc/sv/arvados-docker-cleaner$ <span class="userinput">sudo sh -c 'cat >run' <<'EOF'
+#!/bin/sh
+exec python3 -m arvados_docker.cleaner --quota <b>50G</b>
+EOF</span>
+/etc/sv/arvados-docker-cleaner$ <span class="userinput">sudo chmod +x run log/run</span>
+</code></pre>
+</notextile>
+
+If you are using a different daemon supervisor, or if you want to test the daemon in a terminal window, an equivalent shell command to run arvados-docker-cleaner is:
+
+<notextile>
+<pre><code><span class="userinput">python3 -m arvados_docker.cleaner --quota <b>50G</b></span>
+</code></pre>
+</notextile>
+
+h2. Add a Crunch user account