Steps to use the db2 images with persistent volume in a k8s cluster.

kubernetes/expc/ReadMe.md

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+This document covers how to create a db2instance container with a host Persistent Volume (pv)
+
+## Create a host persistent volume
+For my testing I have used minikube, so had to login to vm and create the folder
+``` sh
+minikube ssh
+mkdir /data/pv0001
+```
+
+Next create a persistent volume in kubernetes using the yaml below
+
+``` yaml
+apiVersion: v1
+kind: PersistentVolume
+metadata:
+  name: pv0001
+spec:
+  accessModes:
+    - ReadWriteOnce
+  capacity:
+    storage: 20Gi
+  hostPath:
+    path: /data/pv0001/
+```
+
+``` bash
+kubectl create -f host_pv.yaml
+```
+
+## Create the db2 instance.
+The angoca/db2-instance:expc image has an installation of db2 in the /opt directory but no instance of db2, we will create the db2 instance, by first creating the container and then running some commands on the container.
+
+### Create the container with the following yaml
+``` yaml
+apiVersion: v1
+kind: Pod
+metadata:
+  name: db2-instance
+  labels:
+    tier: db2-database
+spec:
+  volumes:
+    - name: db2-data-dir
+      hostPath:
+        path: /data/pv0001/
+  containers:
+  - name: db2-instance
+    image: angoca/db2-instance:expc
+    command: ["/bin/sh"]
+    args: ["-c", "while true; do echo hello; sleep 10;done"]
+    ports:
+      - containerPort: 50000
+    volumeMounts:
+      - mountPath: /home
+        name: db2-data-dir
+    securityContext:
+      privileged: true
+```
+``` bash
+kubectl create -f pod-angoca-db2-instance.yaml
+#ssh to the container
+kubectl exec -it db2-angoca-mount bash
+root@db2-angoca-mount:$ cd /tmp/db2_conf/
+root@db2-angoca-mount:/tmp/db2_conf$./createInstance
+root@db2-angoca-mount:/tmp/db2_conf$ su - db2inst1
+db2inst1@db2-angoca-mount:~$ db2sampl
+db2inst1@db2-angoca-mount:~$ exit
+root@db2-angoca-mount:/tmp/db2_conf$ exit
+
+```
+
+The above commands will create the db2 storage files in /home/db2inst1 directory which is actually the pv from the host. Due to this our database data will be persisted across container deletions. We also create a sample db to test connections.
+
+### Forward ports from your local host
+``` shell
+kubectl port-forward db2-instance 50000:50000
+```
+
+Test to make sure you can connect to the db using your favorite database tool.
+
+### Delete the pod
+``` bash
+kubectl delete -f pod-angoca-db2-instance.yaml
+```
+
+
+## Create a new container from the db2inst image with a mounted volume.
+
+There is another image in the angoca repo that has an instance alrady created, we use this image now but with the data of the mounted volume from the previous step.
+
+### Create a container with the following yaml.
+
+``` yaml
+apiVersion: v1
+kind: Pod
+metadata:
+  name: db2-angoca-mount
+  labels:
+    tier: db2-database
+spec:
+  volumes:
+    - name: db2-data-dir
+      hostPath:
+        path: /data/pv0001/
+  containers:
+  - name: db2-angoca-mount-container
+    image: angoca/db2inst1:expc
+    command: ["/bin/sh"]
+    args: ["-c", "/home/db2inst1/sqllib/adm/db2start;while true; do echo hello; sleep 10;done"]
+    ports:
+      - containerPort: 50000
+    volumeMounts:
+      - mountPath: /home
+        name: db2-data-dir
+    securityContext:
+      privileged: true
+
+```
+``` bash
+kubectl create -f pod-angoca-db2inst1-mount.yaml
+#forward the ports
+kubectl port-forward db2-angoca-mount 50000:50000
+```
+
+Thats it!! You should be all set to use this db2 pod from your machine which is running minikube. Try inserting data in some tables, and then destroying the pod and recreating it. The data should be present in the new pod that is created.You can also login to the minikube vm and check contents of the directory, you should see something like below.
+
+``` bash
+C:\Users\mahesh_sawaiker>minikube ssh
+                         _             _
+            _         _ ( )           ( )
+  ___ ___  (_)  ___  (_)| |/')  _   _ | |_      __
+/' _ ` _ `\| |/' _ `\| || , <  ( ) ( )| '_`\  /'__`\
+| ( ) ( ) || || ( ) || || |\`\ | (_) || |_) )(  ___/
+(_) (_) (_)(_)(_) (_)(_)(_) (_)`\___/'(_,__/'`\____)
+
+$ ls /data
+pv0001
+$ ls /data/pv0001
+db2fenc1  db2inst1
+```

kubernetes/expc/host_pv.yaml

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+apiVersion: v1
+kind: PersistentVolume
+metadata:
+  name: pv0001
+spec:
+  accessModes:
+    - ReadWriteOnce
+  capacity:
+    storage: 20Gi
+  hostPath:
+    path: /data/pv0001/

kubernetes/expc/pod-angoca-db2-instance.yaml

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+apiVersion: v1
+kind: Pod
+metadata:
+  name: db2-instance
+  labels:
+    tier: db2-database
+spec:
+  volumes:
+    - name: db2-data-dir
+      hostPath:
+        path: /data/pv0001/
+  containers:
+  - name: db2-instance
+    image: angoca/db2-instance:expc
+    command: ["/bin/sh"]
+    args: ["-c", "while true; do echo hello; sleep 10;done"]
+    ports:
+      - containerPort: 50000
+    volumeMounts:
+      - mountPath: /home
+        name: db2-data-dir
+    securityContext:
+      privileged: true

kubernetes/expc/pod-angoca-db2inst1-mount.yaml

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+apiVersion: v1
+kind: Pod
+metadata:
+  name: db2-angoca-mount
+  labels:
+    tier: db2-database
+spec:
+  volumes:
+    - name: db2-data-dir
+      hostPath:
+        path: /data/pv0001/
+  containers:
+  - name: db2-angoca-mount-container
+    image: angoca/db2inst1:expc
+    command: ["/bin/sh"]
+    args: ["-c", "/home/db2inst1/sqllib/adm/db2start;while true; do echo hello; sleep 10;done"]
+    ports:
+      - containerPort: 50000
+    volumeMounts:
+      - mountPath: /home
+        name: db2-data-dir
+    securityContext:
+      privileged: true