Register a snapshot repository
editRegister a snapshot repository
editYou must register a snapshot repository before you can perform snapshot and restore operations. Use the put snapshot repository API to register or update a snapshot repository. We recommend creating a new snapshot repository for each major version. The valid repository settings depend on the repository type.
If you register the same snapshot repository with multiple clusters, only
one cluster should have write access to the repository. All other clusters
connected to that repository should set the repository to readonly
mode.
The snapshot format can change across major versions, so if you have
clusters on different versions trying to write to the same repository, snapshots
written by one version may not be visible to the other and the repository could
be corrupted. While setting the repository to readonly
on all but one of the
clusters should work with multiple clusters differing by one major version, it
is not a supported configuration.
PUT /_snapshot/my_backup { "type": "fs", "settings": { "location": "my_backup_location" } }
Use the get snapshot API to retrieve information about a registered repository:
GET /_snapshot/my_backup
This request returns the following response:
{ "my_backup": { "type": "fs", "settings": { "location": "my_backup_location" } } }
To retrieve information about multiple repositories, specify a comma-delimited
list of repositories. You can also use a wildcard (*
) when
specifying repository names. For example, the following request retrieves
information about all of the snapshot repositories that start with repo
or
contain backup
:
GET /_snapshot/repo*,*backup*
To retrieve information about all registered snapshot repositories, omit the repository name:
GET /_snapshot
Alternatively, you can specify _all
:
GET /_snapshot/_all
You can unregister a repository using the delete snapshot repository API:
DELETE /_snapshot/my_backup
When a repository is unregistered, Elasticsearch only removes the reference to the location where the repository is storing the snapshots. The snapshots themselves are left untouched and in place.
Shared file system repository
editUse a shared file system repository ("type": "fs"
) to store snapshots on a
shared file system.
To register a shared file system repository, first mount the file system to the
same location on all master and data nodes. Then add the file system’s
path or parent directory to the path.repo
setting in elasticsearch.yml
for
each master and data node. For running clusters, this requires a
rolling restart of each node.
By default, a network file system (NFS) uses user IDs (UIDs) and group IDs (GIDs) to match accounts across nodes. If your shared file system is an NFS and your nodes don’t use the same UIDs and GIDs, update your NFS configuration to account for this.
Supported path.repo
values vary by platform:
Linux and macOS installations support Unix-style paths:
path: repo: - /mount/backups - /mount/long_term_backups
After restarting each node, use the put snapshot
repository API to register the file system repository. Specify the file
system’s path in settings.location
:
PUT /_snapshot/my_fs_backup { "type": "fs", "settings": { "location": "/mount/backups/my_fs_backup_location", "compress": true } }
If you specify a relative path in settings.location
, Elasticsearch resolves the path
using the first value in the path.repo
setting.
Windows installations support both DOS and Microsoft UNC paths. Escaped any backslashes in the paths. For UNC paths, provide the server and share name as a prefix.
After restarting each node, use the put snapshot
repository API to register the file system repository. Specify the file
system’s path in settings.location
:
PUT /_snapshot/my_fs_backup { "type": "fs", "settings": { "location": "E:\\Mount\\Backups\\My_fs_backup_location", "compress": true } }
If you specify a relative path in settings.location
, Elasticsearch resolves the path
using the first value in the path.repo
setting.
Read-only URL repository
editIf you register the same snapshot repository with multiple clusters, only one cluster should have write access to the repository. Having multiple clusters write to the repository at the same time risks corrupting the contents of the repository.
To reduce this risk, you can use URL repositories ("type": "url"
) to give one
or more clusters read-only access to a shared file system repository. As URL
repositories are always read-only, they are a safer and more convenient
alternative to registering a read-only shared filesystem repository.
The URL specified in the url
parameter should point to the root of the shared
filesystem repository.
PUT /_snapshot/my_read_only_url_repository { "type": "url", "settings": { "url": "file:/mount/backups/my_fs_backup_location" } }
The url
parameter supports the following protocols:
-
file
-
ftp
-
http
-
https
-
jar
URLs using the file
protocol must point to the location of a shared filesystem
accessible to all master and data nodes in the cluster. This location must be
registered in the path.repo
setting, similar to a
shared file system repository.
URLs using the ftp
, http
, or https
protocols must be explicitly allowed with the
repositories.url.allowed_urls
setting. This setting supports wildcards (*
)
in place of a host, path, query, or fragment in the URL. For example:
repositories.url.allowed_urls: ["http://www.example.org/root/*", "https://*.mydomain.com/*?*#*"]
URLs using the ftp
, http
, https
, or jar
protocols do not need to
be registered in the path.repo
setting.
Source only repository
editA source repository enables you to create minimal, source-only snapshots that take up to 50% less space on disk. Source only snapshots contain stored fields and index metadata. They do not include index or doc values structures and are not searchable when restored. After restoring a source-only snapshot, you must reindex the data into a new index.
Source repositories delegate to another snapshot repository for storage.
Source only snapshots are only supported if the _source
field is enabled and no source-filtering is applied.
When you restore a source only snapshot:
-
The restored index is read-only and can only serve
match_all
search or scroll requests to enable reindexing. -
Queries other than
match_all
and_get
requests are not supported. -
The mapping of the restored index is empty, but the original mapping is available from the types top
level
meta
element.
When you create a source repository, you must specify the type and name of the delegate repository where the snapshots will be stored:
PUT _snapshot/my_src_only_repository { "type": "source", "settings": { "delegate_type": "fs", "location": "my_backup_location" } }
Repository plugins
editOther repository backends are available in these official plugins:
- repository-s3 for S3 repository support
- repository-hdfs for HDFS repository support in Hadoop environments
- repository-azure for Azure storage repositories
- repository-gcs for Google Cloud Storage repositories
Repository verification
editWhen a repository is registered, it’s immediately verified on all master and data nodes to make sure that it is functional
on all nodes currently present in the cluster. The verify
parameter can be used to explicitly disable the repository
verification when registering or updating a repository:
PUT /_snapshot/my_unverified_backup?verify=false { "type": "fs", "settings": { "location": "my_unverified_backup_location" } }
The verification process can also be executed manually by running the following command:
POST /_snapshot/my_unverified_backup/_verify
It returns a list of nodes where repository was successfully verified or an error message if verification process failed.
Repository cleanup
editRepositories can over time accumulate data that is not referenced by any existing snapshot. This is a result of the data safety guarantees the snapshot functionality provides in failure scenarios during snapshot creation and the decentralized nature of the snapshot creation process. This unreferenced data does in no way negatively impact the performance or safety of a snapshot repository but leads to higher than necessary storage use. In order to clean up this unreferenced data, users can call the cleanup endpoint for a repository which will trigger a complete accounting of the repositories contents and subsequent deletion of all unreferenced data that was found.
POST /_snapshot/my_repository/_cleanup
The response to a cleanup request looks as follows:
{ "results": { "deleted_bytes": 20, "deleted_blobs": 5 } }
Depending on the concrete repository implementation the numbers shown for bytes free as well as the number of blobs removed will either be an approximation or an exact result. Any non-zero value for the number of blobs removed implies that unreferenced blobs were found and subsequently cleaned up.
Please note that most of the cleanup operations executed by this endpoint are automatically executed when deleting any snapshot from a repository. If you regularly delete snapshots, you will in most cases not get any or only minor space savings from using this functionality and should lower your frequency of invoking it accordingly.