kubernetes: arrange for kubelet-plugins directory to be persistent

/usr/libexec/kubernetes/kubelet-plugins is a new path in Kube 1.8 (related to
flexvolumes) which should be persisted. Like /etc/cni and /opt/cni we also need
to arrange for this path to be valid in the host environment (since various
system containers will try and mount bind mount it).

Signed-off-by: Ian Campbell <ijc@docker.com>

projects/kubernetes/cri-containerd/Dockerfile

@@ -48,4 +48,4 @@ FROM scratch
 WORKDIR /
 ENTRYPOINT ["cri-containerd", "-v", "2", "--alsologtostderr", "--network-bin-dir", "/var/lib/cni/opt/bin", "--network-conf-dir", "/var/lib/cni/etc/net.d"]
 COPY --from=build /out /
-LABEL org.mobyproject.config='{"binds": ["/etc/resolv.conf:/etc/resolv.conf", "/run:/run:rshared,rbind", "/dev:/dev", "/tmp:/tmp", "/var:/var:rshared,rbind", "/var/lib/kubeadm:/etc/kubernetes", "/var/lib/cni/etc:/etc/cni:rshared,rbind", "/var/lib/cni/opt:/opt/cni:rshared,rbind", "/run/containerd/containerd.sock:/run/containerd/containerd.sock"], "mounts": [{"type": "cgroup", "options": ["rw","nosuid","noexec","nodev","relatime"]}], "capabilities": ["all"], "rootfsPropagation": "shared", "pid": "host", "runtime": {"mkdir": ["/var/lib/kubeadm", "/var/lib/cni/etc/net.d", "/var/lib/cni/opt"]}}'
+LABEL org.mobyproject.config='{"binds": ["/etc/resolv.conf:/etc/resolv.conf", "/run:/run:rshared,rbind", "/dev:/dev", "/tmp:/tmp", "/var:/var:rshared,rbind", "/var/lib/kubeadm:/etc/kubernetes", "/var/lib/cni/etc:/etc/cni:rshared,rbind", "/var/lib/cni/opt:/opt/cni:rshared,rbind", "/run/containerd/containerd.sock:/run/containerd/containerd.sock", "/var/lib/kubelet-plugins:/usr/libexec/kubernetes/kubelet-plugins:rshared,rbind"], "mounts": [{"type": "cgroup", "options": ["rw","nosuid","noexec","nodev","relatime"]}], "capabilities": ["all"], "rootfsPropagation": "shared", "pid": "host", "runtime": {"mkdir": ["/var/lib/kubeadm", "/var/lib/cni/etc/net.d", "/var/lib/cni/opt", "/var/lib/kubelet-plugins"]}}'

projects/kubernetes/docker.yml

@@ -16,10 +16,11 @@ services:
      - /var/lib/kubeadm:/etc/kubernetes
      - /var/lib/cni/etc:/etc/cni:rshared,rbind
      - /var/lib/cni/opt:/opt/cni:rshared,rbind
+     - /var/lib/kubelet-plugins:/usr/libexec/kubernetes/kubelet-plugins:rshared,rbind
     rootfsPropagation: shared
     command: ["/usr/local/bin/docker-init", "/usr/local/bin/dockerd"]
     runtime:
-      mkdir: ["/var/lib/kubeadm", "/var/lib/cni/etc", "/var/lib/cni/opt"]
+      mkdir: ["/var/lib/kubeadm", "/var/lib/cni/etc", "/var/lib/cni/opt", "/var/lib/kubelet-plugins"]
   - name: kubernetes-image-cache-common
     image: linuxkitprojects/kubernetes-image-cache-common:465c8781efd6664c9a744eb78bf5b90d6ce5db3e
 files:

projects/kubernetes/kube.yml

@@ -42,6 +42,8 @@ files:
     metadata: yaml
   - path: /etc/kubernetes
     symlink: "/var/lib/kubeadm"
+  - path: /usr/libexec/kubernetes/kubelet-plugins
+    symlink: "/var/lib/kubelet-plugins"
   - path: /etc/kubeadm/kube-system.init/50-network.yaml
     source: network.yaml
   - path: /etc/sysctl.d/01-kubernetes.conf

projects/kubernetes/kubernetes/Dockerfile

@@ -75,4 +75,4 @@ WORKDIR /
 ENTRYPOINT ["/usr/bin/kubelet.sh"]
 COPY --from=build /out /
 ENV KUBECONFIG "/etc/kubernetes/admin.conf"
-LABEL org.mobyproject.config='{"binds": ["/dev:/dev", "/etc/resolv.conf:/etc/resolv.conf", "/run:/run:rshared,rbind", "/var:/var:rshared,rbind", "/var/lib/kubeadm:/etc/kubernetes", "/etc/kubelet.sh.conf:/etc/kubelet.sh.conf", "/etc/kubeadm:/etc/kubeadm"], "mounts": [{"type": "cgroup", "options": ["rw","nosuid","noexec","nodev","relatime"]}], "capabilities": ["all"], "rootfsPropagation": "shared", "pid": "host", "runtime": {"mkdir": ["/var/lib/kubeadm", "/var/lib/cni/etc", "/var/lib/cni/opt"], "mounts": [{"type": "bind", "source": "/var/lib/cni/opt", "destination": "/opt/cni", "options": ["rw", "bind"]}, {"type": "bind", "source": "/var/lib/cni/etc", "destination": "/etc/cni", "options": ["rw", "bind"]}]}}'
+LABEL org.mobyproject.config='{"binds": ["/dev:/dev", "/etc/resolv.conf:/etc/resolv.conf", "/run:/run:rshared,rbind", "/var:/var:rshared,rbind", "/var/lib/kubeadm:/etc/kubernetes", "/etc/kubelet.sh.conf:/etc/kubelet.sh.conf", "/etc/kubeadm:/etc/kubeadm", "/var/lib/kubelet-plugins:/usr/libexec/kubernetes/kubelet-plugins:rshared,rbind"], "mounts": [{"type": "cgroup", "options": ["rw","nosuid","noexec","nodev","relatime"]}], "capabilities": ["all"], "rootfsPropagation": "shared", "pid": "host", "runtime": {"mkdir": ["/var/lib/kubeadm", "/var/lib/cni/etc", "/var/lib/cni/opt", "/var/lib/kubelet-plugins"], "mounts": [{"type": "bind", "source": "/var/lib/cni/opt", "destination": "/opt/cni", "options": ["rw", "bind"]}, {"type": "bind", "source": "/var/lib/cni/etc", "destination": "/etc/cni", "options": ["rw", "bind"]}]}}'