Dedicate extra chapter to volumes

SUMMARY.md

@@ -26,6 +26,7 @@
     * [Kubernetes Dashboard](deployment/digital-ocean/dashboard/README.md)
     * [HTTPS](deployment/digital-ocean/https/README.md)
   * [Human Connection](deployment/human-connection/README.md)
+  * [Volumes](deployment/volumes/README.md)
   * [Neo4J DB Backup](deployment/backup.md)
   * [Legacy Migration](deployment/legacy-migration/README.md)
 * [Feature Specification](cypress/features.md)

deployment/human-connection/README.md

@@ -37,6 +37,14 @@ If you have a [kubernets dashboard](../digital-ocean/dashboard/README.md)
 deployed you should switch to namespace `human-connection` in order to
 monitor the state of your deployments.
 
+## Create persistent volumes
+
+While the deployments and services can easily be restored, simply by deleting
+and applying the kubernetes configurations again, certain data is not that
+easily recovered. Therefore we separated persistent volumes from deployments
+and services. There is a [dedicated section](../volumes/README.md). Create those
+persistent volumes once before you apply the configuration.
+
 ## Apply the configuration
 
 ```text

deployment/human-connection/deployment-backend.yaml

@@ -43,15 +43,3 @@
         restartPolicy: Always
         terminationGracePeriodSeconds: 30
   status: {}
----
-  kind: PersistentVolumeClaim
-  apiVersion: v1
-  metadata:
-    name: uploads-claim
-    namespace: human-connection
-  spec:
-    accessModes:
-      - ReadWriteOnce
-    resources:
-      requests:
-        storage: 2Gi

deployment/human-connection/deployment-neo4j.yaml

@@ -57,15 +57,3 @@
             claimName: neo4j-data-claim
         restartPolicy: Always
         terminationGracePeriodSeconds: 30
----
-  kind: PersistentVolumeClaim
-  apiVersion: v1
-  metadata:
-    name: neo4j-data-claim
-    namespace: human-connection
-  spec:
-    accessModes:
-      - ReadWriteOnce
-    resources:
-      requests:
-        storage: 1Gi

deployment/volumes/README.md

@@ -0,0 +1,42 @@
+# Persistent Volumes
+
+At the moment, the application needs two persistent volumes:
+
+* The `/data/` folder where `neo4j` stores its database and
+* the folder `/nitro-backend/public/uploads` where the backend stores uploads.
+
+As a matter of precaution, the persistent volume claims that setup these volumes
+live in a separate folder. You don't want to accidently loose all your data in
+your database by running `kubectl delete -f human-connection/`, do you?
+
+## Create Persistent Volume Claims
+
+Run the following:
+```sh
+# in folder deployments/
+$ kubectl apply -f volumes
+persistentvolumeclaim/neo4j-data-claim created
+persistentvolumeclaim/uploads-claim created 
+```
+
+## Change Reclaim Policy
+
+We recommend to change the `ReclaimPolicy`, so if you delete the persistent
+volume claims, the associated volumes will be released, not deleted:
+
+```sh
+$ kubectl --namespace=human-connection get pv
+
+NAME                                       CAPACITY   ACCESS MODES   RECLAIM POLICY   STATUS   CLAIM                               STORAGECLASS       REASON   AGE
+pvc-bd02a715-66d0-11e9-be52-ba9c337f4551   1Gi        RWO            Delete           Bound    human-connection/neo4j-data-claim   do-block-storage            4m24s
+pvc-bd208086-66d0-11e9-be52-ba9c337f4551   2Gi        RWO            Delete           Bound    human-connection/uploads-claim      do-block-storage            4m12s
+```
+
+Get the volume id from above, then change `ReclaimPolicy` with:
+```sh
+kubectl patch pv <VOLUME-ID> -p '{"spec":{"persistentVolumeReclaimPolicy":"Retain"}}'
+
+# in the above example
+kubectl patch pv pvc-bd02a715-66d0-11e9-be52-ba9c337f4551 -p '{"spec":{"persistentVolumeReclaimPolicy":"Retain"}}'
+kubectl patch pv pvc-bd208086-66d0-11e9-be52-ba9c337f4551 -p '{"spec":{"persistentVolumeReclaimPolicy":"Retain"}}'
+```

deployment/volumes/neo4j-data.yaml

@@ -0,0 +1,12 @@
+---
+  kind: PersistentVolumeClaim
+  apiVersion: v1
+  metadata:
+    name: neo4j-data-claim
+    namespace: human-connection
+  spec:
+    accessModes:
+      - ReadWriteOnce
+    resources:
+      requests:
+        storage: 1Gi

deployment/volumes/uploads.yaml

@@ -0,0 +1,12 @@
+---
+  kind: PersistentVolumeClaim
+  apiVersion: v1
+  metadata:
+    name: uploads-claim
+    namespace: human-connection
+  spec:
+    accessModes:
+      - ReadWriteOnce
+    resources:
+      requests:
+        storage: 2Gi