contrib/docker: add instructions to README

diff --git a/contrib/README b/contrib/README
index 897d619..e5c7e36 100644 (file)
--- a/contrib/README
+++ b/contrib/README
@@ -44,6 +44,21 @@ should look something like this:
   datadir: "/var/lib/collectd/rrd/"
   libdir: "/usr/lib/collectd/"
 
+docker/
+-------
+Sample docker setup using an LD_PRELOAD wrapper to redirect system calls
+accessing /proc and /sys to prefixed bind-mounts inside the container.
+
+Drop your collectd configuration snippets in the
+contrib/docker/collectd.conf.d/ directory, and build an image including them:
+ $ docker build -t my_collectd ./contrib/docker/
+
+Then run it with the required bind-mounts:
+ $ docker run -it --rm \
+    -v /proc:/rootfs/proc:ro -v /sys:/rootfs/sys:ro \
+    --name collectd my_collectd
+ $ docker exec -it collectd collectdctl listval
+
 exec-munin.px
 -------------
   Script to be used with the exec-plugin (see collectd-exec(5) for details)