Merge pull request #75376 from jneczypor/OSDOCS-8392

OSDOCS-8392: Migrate "Deploy an Application - Storage" from rosaworkshop.io

Author: EricPonvelle

_topic_maps/_topic_map_rosa.yml

@@ -190,6 +190,8 @@ Topics:
     File: cloud-experts-deploying-application-deployment
   - Name: Networking
     File: cloud-experts-deploying-application-networking
+  - Name: Storage
+    File: cloud-experts-deploying-application-storage
 ---
 Name: Getting started
 Dir: rosa_getting_started

cloud_experts_tutorials/cloud-experts-deploying-application/cloud-experts-deploying-application-storage.adoc

@@ -0,0 +1,121 @@
+:_mod-docs-content-type: ASSEMBLY
+[id="cloud-experts-deploying-application-storage"]
+= Tutorial: Persistent volumes for cluster storage
+include::_attributes/attributes-openshift-dedicated.adoc[]
+:context: cloud-experts-deploying-application-storage
+
+toc::[]
+
+//rosaworkshop.io content metadata
+//Brought into ROSA product docs 2024-04-30
+
+{rosa-classic-first} and Red Hat OpenShift Service on AWS (ROSA) support storing persistent volumes with either link:https://aws.amazon.com/ebs/[Amazon Web Services (AWS) Elastic Block Store (EBS)] or link:https://aws.amazon.com/efs/[AWS Elastic File System (EFS)].
+
+== Using persistent volumes
+Use the following procedures to create a file, store it on a persistent volume in your cluster, and confirm that it still exists after pod failure and re-creation.
+
+=== Viewing a persistent volume claim
+. Navigate to the cluster's OpenShift web console.
+. Click *Storage* in the left menu, then click *PersistentVolumeClaims* to see a list of all the persistent volume claims. 
+. Click a persistence volume claim to see the size, access mode, storage class, and other additional claim details. 
++
+[NOTE]
+====
+The access mode is `ReadWriteOnce` (RWO). This means that the volume can only be mounted to one node and the pod or pods can read and write to the volume.
+====
+
+=== Storing your file
+
+. In the OSToy app console, click *Persistent Storage* in the left menu.
+. In the *Filename* box, enter a file name with a `.txt` extension, for example `test-pv.txt`.
+. In the *File contents* box, enter a sentence of text, for example `OpenShift is the greatest thing since sliced bread!`.
+. Click *Create file*.
++
+image::cloud-experts-storage-ostoy-createfile.png[]
++
+.Verification
+. Scroll to *Existing files* on the OSToy app console.
+. Click the file you created to see the file name and contents.
++
+image::cloud-experts-storage-ostoy-viewfile.png[]
+
+=== Crashing the pod
+
+. On the OSToy app console, click *Home* in the left menu.
+. Click *Crash pod*.
+
+=== Confirming persistent storage
+
+. Wait for the pod to re-create.
+. On the OSToy app console, click *Persistent Storage* in the left menu.
+. Find the file you created, and open it to view and confirm the contents.
++
+image::cloud-experts-storage-ostoy-existingfile.png[]
+
+.Verification
+The deployment YAML file shows that we mounted link:https://github.com/openshift-cs/rosaworkshop/blob/master/rosa-workshop/ostoy/yaml/ostoy-frontend-deployment.yaml#L61[the directory] `/var/demo_files` to our persistent volume claim.
+
+. Retrieve the name of your front-end pod by running the following command:
++
+[source,terminal]
+----
+$ oc get pods
+----
++
+. Start a secure shell (SSH) session in your container by running the following command:
++
+[source,terminal]
+----
+$ oc rsh <pod_name>
+----
++
+. Go to the directory by running the following command:
++
+[source,terminal]
+----
+$ cd /var/demo_files
+----
++
+. *Optional:* See all the files you created by running the following command:
++
+[source,terminal]
+----
+$ ls
+----
++
+. Open the file to view the contents by running the following command:
++
+[source,terminal]
+----
+$ cat test-pv.txt
+----
++
+. Verify that the output is the text you entered in the OSToy app console.
++
+.Example terminal
+[source,terminal]
+----
+$ oc get pods
+NAME                                  READY     STATUS    RESTARTS   AGE
+ostoy-frontend-5fc8d486dc-wsw24       1/1       Running   0          18m
+ostoy-microservice-6cf764974f-hx4qm   1/1       Running   0          18m
+
+$ oc rsh ostoy-frontend-5fc8d486dc-wsw24
+
+$ cd /var/demo_files/
+
+$ ls
+lost+found   test-pv.txt
+
+$ cat test-pv.txt
+OpenShift is the greatest thing since sliced bread!
+----
+
+=== Ending the session
+
+* Type `exit` in your terminal to quit the session and return to the CLI.
+
+[role="_additional-resources"]
+== Additional resources
+* For more information about persistent volume storage, see xref:../../storage/understanding-persistent-storage.adoc#persistent-volumes_understanding-persistent-storage[Understanding persistent storage].
+* For more information about ROSA storage options, see xref:../../storage/index.adoc#storage-overview[Storage overview].