Systemd/non-Redhat: Add docker healthcheck script

We do the equivalent of #21727 for systemd systems.

Issue #21731

cluster/saltbase/salt/docker/docker-healthcheck

@@ -0,0 +1,44 @@
+#!/bin/bash
+
+# Copyright 2015 The Kubernetes Authors All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# This script is intended to be run periodically, to check the health
+# of docker.  If it detects a failure, it will restart docker using systemctl.
+
+if timeout 10 docker version > /dev/null; then
+  exit 0
+fi
+
+echo "docker failed"
+echo "Giving docker 30 seconds grace before restarting"
+sleep 30
+
+if timeout 10 docker version > /dev/null; then
+  echo "docker recovered"
+  exit 0
+fi
+
+echo "docker still down; triggering docker restart"
+systemctl restart docker
+
+echo "Waiting 60 seconds to give docker time to start"
+sleep 60
+
+if timeout 10 docker version > /dev/null; then
+  echo "docker recovered"
+  exit 0
+fi
+
+echo "docker still failing"