// Module included in the following assemblies:
//
// * disaster_recovery/backing-up-etcd.adoc
// * post_installation_configuration/cluster-tasks.adoc

[id="backing-up-etcd-data_{context}"]
= Backing up etcd data

Follow these steps to back up etcd data by creating an etcd snapshot and backing up the resources for the static pods. This backup can be saved and used at a later time if you need to restore etcd.

[IMPORTANT]
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Only save a backup from a single master host. Do not take a backup from each master host in the cluster.
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.Prerequisites

* You have access to the cluster as a user with the `cluster-admin` role.
* You have checked whether the cluster-wide proxy is enabled.
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[TIP]
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You can check whether the proxy is enabled by reviewing the output of `oc get proxy cluster -o yaml`. The proxy is enabled if the `httpProxy`, `httpsProxy`, and `noProxy` fields have values set.
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.Procedure

. Start a debug session for a master node:
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[source,terminal]
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$ oc debug node/<node_name>
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. Change your root directory to the host:
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[source,terminal]
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sh-4.2# chroot /host
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. If the cluster-wide proxy is enabled, be sure that you have exported the `NO_PROXY`, `HTTP_PROXY`, and `HTTPS_PROXY` environment variables.

. Run the `cluster-backup.sh` script and pass in the location to save the backup to.
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[source,terminal]
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sh-4.4# /usr/local/bin/cluster-backup.sh /home/core/assets/backup
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.Example script output
[source,terminal]
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1bf371f1b5a483927cd01bb593b0e12cff406eb8d7d0acf4ab079c36a0abd3f7
etcdctl version: 3.3.18
API version: 3.3
found latest kube-apiserver-pod: /etc/kubernetes/static-pod-resources/kube-apiserver-pod-7
found latest kube-controller-manager-pod: /etc/kubernetes/static-pod-resources/kube-controller-manager-pod-8
found latest kube-scheduler-pod: /etc/kubernetes/static-pod-resources/kube-scheduler-pod-6
found latest etcd-pod: /etc/kubernetes/static-pod-resources/etcd-pod-2
Snapshot saved at /home/core/assets/backup/snapshot_2020-03-18_220218.db
snapshot db and kube resources are successfully saved to /home/core/assets/backup
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In this example, two files are created in the `/home/core/assets/backup/` directory on the master host:

* `snapshot_<datetimestamp>.db`: This file is the etcd snapshot.
* `static_kuberesources_<datetimestamp>.tar.gz`: This file contains the resources for the static pods. If etcd encryption is enabled, it also contains the encryption keys for the etcd snapshot.
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[NOTE]
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If etcd encryption is enabled, it is recommended to store this second file separately from the etcd snapshot for security reasons. However, this file is required in order to restore from the etcd snapshot.

Keep in mind that etcd encryption only encrypts values, not keys. This means that resource types, namespaces, and object names are unencrypted.
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