title: Setting insecure registry in docker-in-docker image docker daemon
body: <p>Attempting to add an insercure docker registry to a dind image that I run in a concourse task:</p>
  
  <p>I tried beginning my task by running: </p>
  
  <pre><code>export DOCKER_OPTS="$DOCKER_OPTS --insecure-registry=${INSECURE_REG}"
  </code></pre>
  
  <p>and tried spinning up the daemon and compose:</p>
  
  <pre><code>docker daemon --insecure-registry=${INSECURE_REG} &amp;
  docker-compose up
  </code></pre>
  
  <p><strong>However the task errors: server gave http response to https client, and no such image</strong></p>
  
  <p>The whole task looks like this (basically it is a shell script executed in the dind container that ends with a docker-compose):</p>
  
  <pre><code># Connect to insecure docker registry:
  export DOCKER_OPTS="$DOCKER_OPTS --insecure-registry=${INSECURE_REG}"
  
  # Install docker-compose:
  apk add --no-cache py-pip curl
  pip install docker-compose
  
  # Verify docker registry:
  curl http://${INSECURE_REG}/v2/_catalog #curl does return the expected json
  
  sanitize_cgroups() {
    mkdir -p /sys/fs/cgroup
    mountpoint -q /sys/fs/cgroup || \
      mount -t tmpfs -o uid=0,gid=0,mode=0755 cgroup /sys/fs/cgroup
  
    mount -o remount,rw /sys/fs/cgroup
  
    sed -e 1d /proc/cgroups | while read sys hierarchy num enabled; do
      if [ "$enabled" != "1" ]; then
        # subsystem disabled; skip
        continue
      fi
  
      grouping="$(cat /proc/self/cgroup | cut -d: -f2 | grep "\\&lt;$sys\\&gt;")"
      if [ -z "$grouping" ]; then
        # subsystem not mounted anywhere; mount it on its own
        grouping="$sys"
      fi
  
      mountpoint="/sys/fs/cgroup/$grouping"
  
      mkdir -p "$mountpoint"
  
      # clear out existing mount to make sure new one is read-write
      if mountpoint -q "$mountpoint"; then
        umount "$mountpoint"
      fi
  
      mount -n -t cgroup -o "$grouping" cgroup "$mountpoint"
  
      if [ "$grouping" != "$sys" ]; then
        if [ -L "/sys/fs/cgroup/$sys" ]; then
          rm "/sys/fs/cgroup/$sys"
        fi
  
        ln -s "$mountpoint" "/sys/fs/cgroup/$sys"
      fi
    done
  }
  
  # https://github.com/concourse/concourse/issues/324
  sanitize_cgroups
  
  
  # Spin up the stack as described in docker-compose:
  docker daemon --insecure-registry=${INSECURE_REG} &amp;
  docker-compose up
  </code></pre>