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Backup a Small Sharded Cluster with mongodump

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If your sharded cluster holds a small data set, you can connect to a mongos using mongodump. You can create backups of your MongoDB cluster, if your backup infrastructure can capture the entire backup in a reasonable amount of time and if you have a storage system that can hold the complete MongoDB data set.

Read Sharded Cluster Backup Considerations for a high-level overview of important considerations as well as a list of alternate backup tutorials.


By default mongodump issue its queries to the non-primary nodes.


Capture Data


If you use mongodump without specifying a database or collection, mongodump will capture collection data and the cluster meta-data from the config servers.

You cannot use the --oplog option for mongodump when capturing data from mongos. This option is only available when running directly against a replica set member.

You can perform a backup of a sharded cluster by connecting mongodump to a mongos. Use the following operation at your system’s prompt:

mongodump --host --port 27017

mongodump will write BSON files that hold a copy of data stored in the sharded cluster accessible via the mongos listening on port 27017 of the host.

Restore Data

Backups created with mongodump do not reflect the chunks or the distribution of data in the sharded collection or collections. Like all mongodump output, these backups contain separate directories for each database and BSON files for each collection in that database.

You can restore mongodump output to any MongoDB instance, including a standalone, a replica set, or a new sharded cluster. When restoring data to sharded cluster, you must deploy and configure sharding before restoring data from the backup. See Deploy a Sharded Cluster for more information.