Convert site to Hugo (#8316)

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+---
+title: Backups
+content_template: templates/task
+---
+
+{{% capture overview %}}
+The state of a Kubernetes cluster is kept in the etcd datastore.
+This page shows how to backup and restore the etcd shipped with
+the Canonical Distribution of Kubernetes. Backing up application specific data,
+normally stored in a persistent volume, is outside the scope of this
+document.
+{{% /capture %}}
+
+{{% capture prerequisites %}}
+This page assumes you have a working Juju deployed cluster.
+{{% /capture %}}
+
+{{% capture steps %}}
+## Snapshot etcd data
+
+The `snapshot` action of the etcd charm allows the operator to snapshot
+a running cluster's data for use in cloning,
+backing up, or migrating to a new cluster.
+
+    juju run-action etcd/0 snapshot 
+
+This will create a snapshot in `/home/ubuntu/etcd-snapshots` by default.
+
+## Restore etcd data
+
+The etcd charm is capable of restoring its data from a cluster-data snapshot
+via the `restore` action.
+This comes with caveats and a very specific path to restore a cluster:
+The cluster must be in a state of only having a single member. So it's best to
+deploy a new cluster using the etcd charm, without adding any additional units.
+
+```
+juju deploy etcd new-etcd
+```
+
+The above code snippet will deploy a single unit of etcd, as 'new-etcd'
+
+```
+juju run-action etcd/0 restore target=/mnt/etcd-backups
+```
+
+Once the restore action has completed, evaluate the cluster health. If the unit
+is healthy, you may resume scaling the application to meet your needs.
+
+- **param** target: destination directory to save the existing data.
+
+- **param** skip-backup: Don't backup any existing data.
+
+
+## Migrating an etcd cluster
+Using the above snapshot and restore operations, migrating etcd is a fairly easy task.
+
+**Step 1:** Snapshot your existing cluster. This is encapsulated in the `snapshot`
+action.
+
+```
+juju run-action etcd/0 snapshot
+```
+
+Results:
+
+```
+Action queued with id: b46d5d6f-5625-4320-8cda-b611c6ae580c
+```
+
+**Step 2:** Check the status of the action so you can grab the snapshot and verify
+the sum. The `copy.cmd` result output is a copy/paste command for you to download
+the exact snapshot that you just created.
+
+Download the snapshot archive from the unit that created the snapshot and verify
+the sha256 sum
+
+```
+juju show-action-output b46d5d6f-5625-4320-8cda-b611c6ae580c
+```
+
+Results:
+
+```
+results:
+  copy:
+    cmd: juju scp etcd/0:/home/ubuntu/etcd-snapshots/etcd-snapshot-2016-11-09-02.41.47.tar.gz
+      .
+  snapshot:
+    path: /home/ubuntu/etcd-snapshots/etcd-snapshot-2016-11-09-02.41.47.tar.gz
+    sha256: 1dea04627812397c51ee87e313433f3102f617a9cab1d1b79698323f6459953d
+    size: 68K
+status: completed
+```
+
+Copy the snapshot to the local disk and then check the sha256sum. 
+
+```
+juju scp etcd/0:/home/ubuntu/etcd-snapshots/etcd-snapshot-2016-11-09-02.41.47.tar.gz .
+sha256sum etcd-snapshot-2016-11-09-02.41.47.tar.gz
+```
+
+**Step 3:** Deploy the new cluster leader, and attach the snapshot:
+
+```
+juju deploy etcd new-etcd --resource snapshot=./etcd-snapshot-2016-11-09-02.41.47.tar.gz
+```
+
+**Step 4:** Reinitialize the master with the data from the resource we just attached
+in step 3.
+
+```
+juju run-action new-etcd/0 restore
+```
+
+
+{{% /capture %}}
+
+{{% capture discussion %}}
+## Known Limitations
+
+#### Loss of PKI warning
+
+If you destroy the leader - identified with the `*` text next to the unit number in status:
+all TLS pki will be lost. No PKI migration occurs outside
+of the units requesting and registering the certificates.
+
+{{< caution >}}
+**Caution:**  Mismanaging this configuration will result in locking yourself
+out of the cluster, and can potentially break existing deployments in very
+strange ways relating to x509 validation of certificates, which affects both
+servers and clients.
+{{< /caution >}}
+
+#### Restoring from snapshot on a scaled cluster
+
+Restoring from a snapshot on a scaled cluster will result in a broken cluster.
+Etcd performs clustering during unit turn-up, and state is stored in Etcd itself.
+During the snapshot restore phase, a new cluster ID is initialized, and peers
+are dropped from the snapshot state to enable snapshot restoration. Please
+follow the migration instructions above in the restore action description.
+{{% /capture %}}
+
+