lab 7 snapshot

acend · Sep 5, 2024 · a305fd5 · a305fd5
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diff --git a/Dockerfile b/Dockerfile
@@ -25,12 +25,12 @@ RUN wkhtmltopdf --enable-internal-links --enable-local-file-access \
 
 FROM docker.io/nginxinc/nginx-unprivileged:1.27-alpine
 
-LABEL maintainer tim-koko.ch
-LABEL org.opencontainers.image.title "acend.ch's KubeVirt Basics Training"
-LABEL org.opencontainers.image.description "Container with acend.ch's KubeVirt Training content"
-LABEL org.opencontainers.image.authors tim-koko.ch
-LABEL org.opencontainers.image.source https://github.com/acend/kubevirt-basics-training/
-LABEL org.opencontainers.image.licenses CC-BY-SA-4.0
+LABEL maintainer=tim-koko.ch
+LABEL org.opencontainers.image.title="acend.ch's KubeVirt Basics Training"
+LABEL org.opencontainers.image.description="Container with acend.ch's KubeVirt Training content"
+LABEL org.opencontainers.image.authors=tim-koko.ch
+LABEL org.opencontainers.image.source=https://github.com/acend/kubevirt-basics-training/
+LABEL org.opencontainers.image.licenses=CC-BY-SA-4.0
 
 EXPOSE 8080
 

diff --git a/content/en/docs/07/75_snapshot.md b/content/en/docs/07/75_snapshot.md
@@ -0,0 +1,373 @@
+---
+title: "7.5 Snapshot and Restore"
+weight: 750
+labfoldernumber: "07"
+sectionnumber: 7.5
+description: >
+  Snapshot and restore a virtual machine
+---
+
+KubeVirt provides a snapshot and restore functionality. This feature is only available if your storage driver supports `VolumeSnapshots` and a `VolumeSnapshotClass` is configured.
+
+You can list the available `VolumeSnapshotClass` with:
+```yaml
+kubectl get volumesnapshotclass --namespace=$USER
+```
+```
+NAME                    DRIVER               DELETIONPOLICY   AGE
+longhorn-snapshot-vsc   driver.longhorn.io   Delete           21d
+```
+
+You can snapshot virtual machines in a running state or in the stopped state. Using the QEMU guest agent the snapshot can
+temporarily freeze your VM to get a consistent backup.
+
+
+## {{% task %}} Prepare a virtual machine with a persistent disk
+
+We want to snapshot a virtual machine with a persistent disk. We need to prepare our disk and virtual machine to be
+snapshotted.
+
+
+### {{% task %}} Prepare persistent disk
+
+First, we need to create a persistent disk. We use a DataVolume which imports a container disk and saves it to a persistent
+volume. Create a file `dv_{{% param "labsubfolderprefix" %}}{{% param "labfoldernumber" %}}-cirros.yaml` with the
+following specification:
+
+```yaml
+apiVersion: cdi.kubevirt.io/v1beta1
+kind: DataVolume
+metadata:
+  name: {{% param "labsubfolderprefix" %}}{{% param "labfoldernumber" %}}-cirros-disk
+spec:
+  source:
+    registry:
+      url: "docker://{{% param "cirrosCDI" %}}"
+  pvc:
+    accessModes:
+      - ReadWriteOnce
+    resources:
+      requests:
+        storage: 256Mi
+```
+
+Create the data volume with:
+```shell
+kubectl create -f dv_{{% param "labsubfolderprefix" %}}{{% param "labfoldernumber" %}}-cirros-disk.yaml --namespace=$USER
+```
+
+
+### {{% task %}} Create a virtual machine using the provisioned disk
+
+Create a file `vm_{{% param "labsubfolderprefix" %}}{{% param "labfoldernumber" %}}-snapshot.yaml` for your virtual
+machine and add the following content:
+
+```yaml
+apiVersion: kubevirt.io/v1
+kind: VirtualMachine
+metadata:
+  name: {{% param "labsubfolderprefix" %}}{{% param "labfoldernumber" %}}-snapshot
+spec:
+  running: false
+  template:
+    metadata:
+      labels:
+        kubevirt.io/domain: {{% param "labsubfolderprefix" %}}{{% param "labfoldernumber" %}}-snapshot
+    spec:
+      domain:
+        devices:
+          disks:
+            - name: harddisk
+              disk:
+                bus: virtio
+            - name: cloudinitdisk
+              disk:
+                bus: virtio
+          interfaces:
+            - name: default
+              masquerade: {}
+        resources:
+          requests:
+            memory: 64M
+      networks:
+        - name: default
+          pod: {}
+      volumes:
+        - name: harddisk
+          persistentVolumeClaim:
+            claimName: {{% param "labsubfolderprefix" %}}{{% param "labfoldernumber" %}}-cirros-disk
+        - name: cloudinitdisk
+          cloudInitNoCloud:
+            userData: |
+              #cloud-config
+```
+
+Create the virtual machine with:
+```shell
+kubectl create -f vm_{{% param "labsubfolderprefix" %}}{{% param "labfoldernumber" %}}-snapshot.yaml --namespace=$USER
+```
+
+Start your virtual machine with:
+```shell
+virtctl start {{% param "labsubfolderprefix" %}}{{% param "labfoldernumber" %}}-snapshot --namespace=$USER
+```
+
+
+### {{% task %}} Edit a file in your virtual machine
+
+Now we make a file change and validate if the change is persistent.
+
+Enter the virtual machine with:
+```yaml
+virtctl console {{% param "labsubfolderprefix" %}}{{% param "labfoldernumber" %}}-snapshot --namespace=$USER
+```
+
+Whenever you see the login prompt CirrOS shows the user and the default password.
+```shell
+  ____               ____  ____
+ / __/ __ ____ ____ / __ \/ __/
+/ /__ / // __// __// /_/ /\ \ 
+\___//_//_/  /_/   \____/___/ 
+   http://cirros-cloud.net
+
+
+login as 'cirros' user. default password: 'gocubsgo'. use 'sudo' for root.
+```
+
+Let's get rid of this message and replace it with our own. Login with the credentials and change our `/etc/issue` file.
+```shell
+sudo cp /etc/issue /etc/issue.orig
+echo "Greetings from the KubeVirt Training. This is a CirrOS virtual machine." | sudo tee /etc/issue
+```
+
+Check that the greeting is printed correctly by logging out:
+```shell
+exit
+```
+```
+Greetings from the KubeVirt Training. This is a CirrOS virtual machine.
+{{% param "labsubfolderprefix" %}}{{% param "labfoldernumber" %}}-snapshot login:
+```
+
+Now restart the virtual machine to verify the change was persistent.
+```shell
+sudo reboot
+```
+After the restart completed you should see your new Greeting message.
+```
+  ____               ____  ____
+ / __/ __ ____ ____ / __ \/ __/
+/ /__ / // __// __// /_/ /\ \ 
+\___//_//_/  /_/   \____/___/ 
+   http://cirros-cloud.net
+
+
+Greetings from the KubeVirt Training. This is a CirrOS virtual machine.
+```
+
+
+## {{% task %}} Create a snapshot of the virtual machine
+
+This is our configuration we want to save. We now create a snapshot of the virtual machine at this time.
+
+Create a file `vmsnapshot_{{% param "labsubfolderprefix" %}}{{% param "labfoldernumber" %}}-snapshot-snap.yaml` with the following content:
+
+```yaml
+apiVersion: snapshot.kubevirt.io/v1beta1
+kind: VirtualMachineSnapshot
+metadata:
+  name: {{% param "labsubfolderprefix" %}}{{% param "labfoldernumber" %}}-snapshot-snap
+spec:
+  source:
+    apiGroup: kubevirt.io
+    kind: VirtualMachine
+    name: {{% param "labsubfolderprefix" %}}{{% param "labfoldernumber" %}}-snapshot
+```
+
+Start the snapshot process by creating the VirtualMachineSnapshot:
+```yaml
+kubectl create -f vmsnapshot_{{% param "labsubfolderprefix" %}}{{% param "labfoldernumber" %}}-snapshot-snap.yaml
+```
+
+Make sure you wait until the snapshot is ready. You can issue the following command to wait until the snapshot is ready:
+```shell
+kubectl wait vmsnapshot {{% param "labsubfolderprefix" %}}{{% param "labfoldernumber" %}}-snapshot-snap --for condition=Ready
+```
+It should complete with:
+```
+virtualmachinesnapshot.snapshot.kubevirt.io/{{% param "labsubfolderprefix" %}}{{% param "labfoldernumber" %}}-snapshot-snap condition met
+```
+
+You can list your snapshots with:
+```shell
+kubectl get virtualmachinesnapshot --namespace=$USER
+```
+The output should be similar to:
+```
+NAME                  SOURCEKIND       SOURCENAME       PHASE       READYTOUSE   CREATIONTIME   ERROR
+{{% param "labsubfolderprefix" %}}{{% param "labfoldernumber" %}}-snapshot-snap   VirtualMachine   {{% param "labsubfolderprefix" %}}{{% param "labfoldernumber" %}}-snapshot   Succeeded   true         102s 
+```
+
+You can describe the resource and have a look at the status of the `VirtualMachineSnapshot` and its
+subresource `VirtualMachineSnapshotContent`.
+```shell
+kubectl describe virtualmachinesnapshot --namespace=$USER
+kubectl describe virtualmachinesnapshotcontent --namespace=$USER
+```
+
+```yaml
+apiVersion: snapshot.kubevirt.io/v1beta1
+kind: VirtualMachineSnapshot
+metadata:
+  [...]
+  name: {{% param "labsubfolderprefix" %}}{{% param "labfoldernumber" %}}-snapshot-snap
+status:
+  [...]
+  creationTime: "2024-09-05T08:34:31Z"
+  indications:
+    - Online
+    - NoGuestAgent
+  phase: Succeeded
+  readyToUse: true
+  snapshotVolumes:
+    excludedVolumes:
+      - cloudinitdisk
+    includedVolumes:
+      - harddisk
+  [...]
+```
+
+For example in the status of the VirtualMachineSnapshot description you may find information what volumes are in the snapshot.
+
+* `status.indications`: Information how the snapshot was made.
+  * `Online`: The VM was running during snapshot creation.
+  * `GuestAgent` QEMU guest agent was running during snapshot creation.
+  * `NoGuestAgent` QEMU guest agent was not running during snapshot creation or the QEMU guest agent could not be used due to an error.
+* `status.snapshotVolumes`: Information of which volumes are included
+
+Snapshots also include your virtual machine metadata `spec.template.metadata` and the specification `spec.template.spec`.
+
+
+## {{% task %}} Changing our Greeting message again
+
+Enter the virtual machine with:
+```yaml
+virtctl console {{% param "labsubfolderprefix" %}}{{% param "labfoldernumber" %}}-snapshot --namespace=$USER
+```
+
+Change the Greeting message again:
+```shell
+sudo cp /etc/issue /etc/issue.bak
+echo "Hello" | sudo tee /etc/issue
+```
+
+Now restart the virtual machine again and verify the change was persistent.
+```shell
+sudo reboot
+```
+After the restart completed you should see your new Hello message.
+
+Beside changing a file we add a label `acend.ch/training: kubevirt` to our VirtualMachine metadata `{{% param "labsubfolderprefix" %}}{{% param "labfoldernumber" %}}-snapshot`.
+
+You can do this by patching your virtual machine with:
+```shell
+kubectl patch virtualmachine {{% param "labsubfolderprefix" %}}{{% param "labfoldernumber" %}}-snapshot --type='json' -p='[{"op": "add", "path": "/spec/template/metadata/labels/acend.ch~1training", "value":"kubevirt"}]' --namespace=$USER
+```
+```
+virtualmachine.kubevirt.io/{{% param "labsubfolderprefix" %}}{{% param "labfoldernumber" %}}-snapshot patched
+```
+
+Describe the virtual machine to check if the label is present:
+```shell
+kubectl describe virtualmachine {{% param "labsubfolderprefix" %}}{{% param "labfoldernumber" %}}-snapshot --namespace=$USER
+```
+```
+API Version:  kubevirt.io/v1
+Kind:         VirtualMachine
+Name:         {{% param "labsubfolderprefix" %}}{{% param "labfoldernumber" %}}-snapshot
+[...]
+Spec:
+  Running:  true
+  Template:
+    Metadata:
+      Labels:
+        acend.ch/training:   kubevirt
+        kubevirt.io/domain:  {{% param "labsubfolderprefix" %}}{{% param "labfoldernumber" %}}-snapshot
+[...]
+```
+
+
+## {{% task %}} Restoring a Virtual Machine
+
+Now you decide to restore your snapshot. Make sure your virtual machine is stopped.
+
+```shell
+virtctl stop {{% param "labsubfolderprefix" %}}{{% param "labfoldernumber" %}}-snapshot --namespace=$USER
+```
+
+Create the file `{{% param "labsubfolderprefix" %}}{{% param "labfoldernumber" %}}-snapshot-restore.yaml` with the following content:
+```yaml
+apiVersion: snapshot.kubevirt.io/v1beta1
+kind: VirtualMachineRestore
+metadata:
+  name: {{% param "labsubfolderprefix" %}}{{% param "labfoldernumber" %}}-snapshot-restore
+spec:
+  target:
+    apiGroup: kubevirt.io
+    kind: VirtualMachine
+    name: {{% param "labsubfolderprefix" %}}{{% param "labfoldernumber" %}}-snapshot
+  virtualMachineSnapshotName: {{% param "labsubfolderprefix" %}}{{% param "labfoldernumber" %}}-snapshot-snap
+```
+
+Start the restore process by creating the VirtualMachineRestore:
+```shell
+kubectl create -f vmsnapshot_{{% param "labsubfolderprefix" %}}{{% param "labfoldernumber" %}}-snapshot-restore.yaml --namespace=$USER
+```
+
+Make sure you wait until the restore is done. You can use the following command to wait until the restore is finished:
+```shell
+kubectl wait vmrestore {{% param "labsubfolderprefix" %}}{{% param "labfoldernumber" %}}-snapshot-restore --for condition=Ready --namespace=$USER
+```
+It should complete with:
+```
+virtualmachinerestore.snapshot.kubevirt.io/{{% param "labsubfolderprefix" %}}{{% param "labfoldernumber" %}}-snapshot-restore condition met
+```
+
+
+## {{% task %}} Check the restored virtual machine
+
+Start the virtual machine again with:
+```shell
+virtctl start {{% param "labsubfolderprefix" %}}{{% param "labfoldernumber" %}}-snapshot --namespace=$USER
+```
+
+Whenever the restore was successful out `Hello` greeting should be gone and we should see the following Greeting again.
+Open the console to check the greeting:
+```
+  ____               ____  ____
+ / __/ __ ____ ____ / __ \/ __/
+/ /__ / // __// __// /_/ /\ \ 
+\___//_//_/  /_/   \____/___/ 
+   http://cirros-cloud.net
+
+
+Greetings from the KubeVirt Training. This is a CirrOS virtual machine.
+```
+
+What about the label on the virtual machine manifest? Describe the virtual machine with and validate that it has been removed as well:
+```shell
+kubectl describe virtualmachine {{% param "labsubfolderprefix" %}}{{% param "labfoldernumber" %}}-snapshot --namespace=$USER
+```
+```
+API Version:  kubevirt.io/v1
+Kind:         VirtualMachine
+Name:         {{% param "labsubfolderprefix" %}}{{% param "labfoldernumber" %}}-snapshot
+[...]
+Spec:
+  Running:  true
+  Template:
+    Metadata:
+      Labels:
+        kubevirt.io/domain:  {{% param "labsubfolderprefix" %}}{{% param "labfoldernumber" %}}-snapshot
+[...]
+```
diff --git a/content/en/docs/07/75_resizing-disks.md → content/en/docs/07/76_resizing-disks.md b/content/en/docs/07/75_resizing-disks.md → content/en/docs/07/76_resizing-disks.md