deploy: provide an alternative volume mount for /dev

The gluster-setup.sh script in the glusterfs-server container now chceks
for the HOST_DEV_DIR environment variable and will 'mount --rbind' the
alternative path to /dev from the host to /dev in the container. This is
needed to allow access to *all* devices on the host, including ones that
get dynamically allocated or hot-plugged.

See-also: gluster/gluster-containers#115
Signed-off-by: Niels de Vos <ndevos@redhat.com>

Author: nixpanic

deploy/kube-templates/glusterfs-daemonset.yaml

@@ -24,6 +24,9 @@ spec:
         imagePullPolicy: IfNotPresent
         name: glusterfs
         env:
+        # alternative for /dev volumeMount to enable access to *all* devices
+        - name: HOST_DEV_DIR
+          value: "/mnt/host-dev"
         # set GLUSTER_BLOCKD_STATUS_PROBE_ENABLE to "1" so the
         # readiness/liveness probe validate gluster-blockd as well
         - name: GLUSTER_BLOCKD_STATUS_PROBE_ENABLE
@@ -49,10 +52,8 @@ spec:
           mountPath: "/var/log/glusterfs"
         - name: glusterfs-config
           mountPath: "/var/lib/glusterd"
-        - name: glusterfs-dev-disk
-          mountPath: "/dev/disk"
-        - name: glusterfs-dev-mapper
-          mountPath: "/dev/mapper"
+        - name: glusterfs-host-dev
+          mountPath: "/mnt/host-dev"
         - name: glusterfs-misc
           mountPath: "/var/lib/misc/glusterfsd"
         - name: glusterfs-cgroup
@@ -106,12 +107,9 @@ spec:
       - name: glusterfs-config
         hostPath:
           path: "/var/lib/glusterd"
-      - name: glusterfs-dev-disk
+      - name: glusterfs-host-dev
         hostPath:
-          path: "/dev/disk"
-      - name: glusterfs-dev-mapper
-        hostPath:
-          path: "/dev/mapper"
+          path: "/dev"
       - name: glusterfs-misc
         hostPath:
           path: "/var/lib/misc/glusterfsd"

deploy/ocp-templates/glusterfs-template.yaml

@@ -37,6 +37,8 @@ objects:
           imagePullPolicy: IfNotPresent
           name: glusterfs
           env:
+          - name: HOST_DEV_DIR
+            value: "${HOST_DEV_DIR}"
           - name: GLUSTER_BLOCKD_STATUS_PROBE_ENABLE
             value: "${GLUSTER_BLOCKD_STATUS_PROBE_ENABLE}"
           - name: GB_GLFS_LRU_COUNT
@@ -60,10 +62,8 @@ objects:
             mountPath: "/var/log/glusterfs"
           - name: glusterfs-config
             mountPath: "/var/lib/glusterd"
-          - name: glusterfs-dev-disk
-            mountPath: "/dev/disk"
-          - name: glusterfs-dev-mapper
-            mountPath: "/dev/mapper"
+          - name: glusterfs-host-dev
+            mountPath: "${HOST_DEV_DIR}"
           - name: glusterfs-misc
             mountPath: "/var/lib/misc/glusterfsd"
           - name: glusterfs-cgroup
@@ -100,7 +100,7 @@ objects:
             periodSeconds: 25
             successThreshold: 1
             failureThreshold: 50
-          terminationMessagePath: "/dev/termination-log"
+          terminationMessagePath: "/var/log/termination.log"
         volumes:
         - name: glusterfs-heketi
           hostPath:
@@ -119,12 +119,9 @@ objects:
         - name: glusterfs-config
           hostPath:
             path: "/var/lib/glusterd"
-        - name: glusterfs-dev-disk
+        - name: glusterfs-host-dev
           hostPath:
-            path: "/dev/disk"
-        - name: glusterfs-dev-mapper
-          hostPath:
-            path: "/dev/mapper"
+            path: "/dev"
         - name: glusterfs-misc
           hostPath:
             path: "/var/lib/misc/glusterfsd"
@@ -161,3 +158,8 @@ parameters:
   description: This value is to set tcmu runner log directory
   value: "/var/log/glusterfs/gluster-block"
   required: true
+- name: HOST_DEV_DIR
+  displayName: Alternative path to /dev in the container
+  description: Volume mount point of /dev from the host so that the container can access all devices.
+  value: "/mnt/host-dev"
+  required: true