Merge pull request #9661 from marun/dind-enable-overlay

Merged by openshift-bot

Author: OpenShift Bot

contrib/vagrant/provision-util.sh

@@ -209,9 +209,10 @@ os::provision::base-provision() {
   local origin_root=$1
   local is_master=${2:-false}
 
-  # Ensure that secrets can be correctly mounted for pods.
   if os::provision::in-container; then
+    # Ensure that secrets can be correctly mounted for pods.
     mount --make-shared /
+    os::provision::enable-overlay-storage
   fi
 
   # Add a convenience symlink to the gopath repo
@@ -399,3 +400,36 @@ os::provision::wait-for-node-config() {
   os::provision::wait-for-condition "${msg}" "${condition}" \
     "${OS_WAIT_FOREVER}"
 }
+
+# Enable overlayfs for dind if it can be tested to work.
+os::provision::enable-overlay-storage() {
+  local storage_dir=${1:-/var/lib/docker}
+
+  local msg="WARNING: Unable to enable overlay storage for docker-in-docker"
+
+  if grep -q overlay /proc/filesystems; then
+    # Smoke test the overlay filesystem:
+
+    # 1. create smoke dir in the storage dir being mounted
+    local d="${storage_dir}/smoke"
+    mkdir -p "${d}/upper" "${d}/lower" "${d}/work" "${d}/mount"
+
+    # 2. try to mount an overlay fs on top of the smoke dir
+    local overlay_works=1
+    mount -t overlay overlay\
+          -o"lowerdir=${d}/lower,upperdir=${d}/upper,workdir=${d}/work"\
+          "${d}/mount" &&\
+    # 3. try to write a file in the overlay mount
+          echo foo > "${d}/mount/probe" || overlay_works=
+
+    umount -f "${d}/mount" || true
+    rm -rf "${d}" || true
+
+    if [[ -n "${overlay_works}" ]]; then
+      msg="Enabling overlay storage for docker-in-docker"
+      sed -i -e 's+vfs+overlay+' /etc/sysconfig/docker-storage
+    fi
+  fi
+
+  echo "${msg}"
+}

hack/dind-cluster.sh

@@ -149,6 +149,8 @@ function start() {
   sudo modprobe openvswitch
   sudo modprobe br_netfilter 2> /dev/null || true
   sudo sysctl -w net.bridge.bridge-nf-call-iptables=0 > /dev/null
+  # overlayfs, if available, will be faster than vfs
+  sudo modprobe overlay 2> /dev/null || true
   mkdir -p "${CONFIG_ROOT}"
 
   if [[ "${SKIP_BUILD}" = "true" ]]; then

images/dind/Dockerfile

@@ -40,12 +40,9 @@ RUN dnf -y update && dnf -y install git golang hg tar make findutils \
 # sshd should be enabled as needed
 RUN systemctl disable sshd.service
 
-## Configure dind
-ENV DIND_COMMIT 81aa1b507f51901eafcfaad70a656da376cf937d
-RUN curl -fL "https://raw.githubusercontent.com/docker/docker/${DIND_COMMIT}/hack/dind" \
-  -o /usr/local/bin/dind && chmod +x /usr/local/bin/dind
-RUN mkdir -p /etc/systemd/system/docker.service.d
-COPY dind.conf /etc/systemd/system/docker.service.d/
+# Default storage to vfs.  overlay will be enabled at runtime if available.
+RUN echo "DOCKER_STORAGE_OPTIONS=--storage-driver vfs" >\
+ /etc/sysconfig/docker-storage
 
 RUN systemctl enable docker