MongoDB Backup Methods¶
When deploying MongoDB in production, you should have a strategy for capturing and restoring backups in the case of data loss events.
Back Up with Atlas¶
MongoDB Atlas, the hosted MongoDB service option in the cloud, offers two fully-managed methods for backups:
Cloud Backups, which utilize the native snapshot functionality of the deployment's cloud service provider to offer robust backup options. Cloud Backups provide:
- Legacy Backups (Deprecated), which take incremental backups of data in your deployment.
Back Up with MongoDB Cloud Manager or Ops Manager¶
MongoDB Cloud Manager is a hosted back up, monitoring, and automation service for MongoDB. MongoDB Cloud Manager supports backing up and restoring MongoDB replica sets and sharded clusters from a graphical user interface.
MongoDB Cloud Manager¶
The MongoDB Cloud Manager supports the backing up and restoring of MongoDB deployments.
MongoDB Cloud Manager continually backs up MongoDB replica sets and sharded clusters by reading the oplog data from your MongoDB deployment. MongoDB Cloud Manager creates snapshots of your data at set intervals, and can also offer point-in-time recovery of MongoDB replica sets and sharded clusters.
Sharded cluster snapshots are difficult to achieve with other MongoDB backup methods.
With Ops Manager, MongoDB subscribers can install and run the same core software that powers MongoDB Cloud Manager on their own infrastructure. Ops Manager is an on-premise solution that has similar functionality to MongoDB Cloud Manager and is available with Enterprise Advanced subscriptions.
Back Up by Copying Underlying Data Files¶
For encrypted storage engines that
AES256-GCM encryption mode,
AES256-GCM requires that every
process use a unique counter block value with the key.
For encrypted storage engine
- Restoring from Hot Backup
- Starting in 4.2, if you restore from files taken via "hot"
backup (i.e. the
mongodis running), MongoDB can detect "dirty" keys on startup and automatically rollover the database key to avoid IV (Initialization Vector) reuse.
- Restoring from Cold Backup
However, if you restore from files taken via "cold" backup (i.e. the
mongodis not running), MongoDB cannot detect "dirty" keys on startup, and reuse of IV voids confidentiality and integrity guarantees.
Starting in 4.2, to avoid the reuse of the keys after restoring from a cold filesystem snapshot, MongoDB adds a new command-line option
--eseDatabaseKeyRollover. When started with the
mongodinstance rolls over the database keys configured with
AES256-GCMcipher and exits.
- In general, if using filesystem based backups for MongoDB Enterprise 4.2+, use the "hot" backup feature, if possible.
- For MongoDB Enterprise versions 4.0 and earlier, if you use
AES256-GCMencryption mode, do not make copies of your data files or restore from filesystem snapshots ("hot" or "cold").
Back Up with Filesystem Snapshots¶
You can create a backup of a MongoDB deployment by making a copy of MongoDB's underlying data files.
If the volume where MongoDB stores its data files supports point-in-time snapshots, you can use these snapshots to create backups of a MongoDB system at an exact moment in time. File system snapshots are an operating system volume manager feature, and are not specific to MongoDB. With file system snapshots, the operating system takes a snapshot of the volume to use as a baseline for data backup. The mechanics of snapshots depend on the underlying storage system. For example, on Linux, the Logical Volume Manager (LVM) can create snapshots. Similarly, Amazon’s EBS storage system for EC2 supports snapshots.
To get a correct snapshot of a running
mongod process, you
must have journaling enabled and the journal must reside on the same
logical volume as the other MongoDB data files. Without journaling
enabled, there is no guarantee that the snapshot will be consistent or
To get a consistent snapshot of a sharded cluster, you must disable the balancer and capture a snapshot from every shard as well as a config server at approximately the same moment in time.
For more information, see the Back Up and Restore with Filesystem Snapshots and Back Up a Sharded Cluster with File System Snapshots for complete instructions on using LVM to create snapshots.
Back Up with
If your storage system does not support snapshots, you can copy the
files directly using
rsync, or a similar tool. Since
copying multiple files is not an atomic operation, you must stop all
writes to the
mongod before copying the files. Otherwise, you will
copy the files in an invalid state.
Backups produced by copying the underlying data do not support point
in time recovery for replica sets and are difficult to manage for
larger sharded clusters. Additionally, these backups are larger
because they include the indexes and duplicate underlying storage
padding and fragmentation.
mongodump, by contrast, creates
Back Up with
mongodump reads data from a MongoDB database and
creates high fidelity BSON files which the
tool can use to populate a MongoDB database.
mongorestore are simple and
efficient tools for backing up and restoring small
MongoDB deployments, but are not ideal for capturing backups of larger
When connected to a MongoDB instance,
mongod performance. If your data is larger
than system memory, the queries will push the working set out of
memory, causing page faults.
Applications can continue to modify data while
captures the output. For replica sets,
--oplog option to include in its
output oplog entries that occur during the
operation. This allows the corresponding
operation to replay the captured oplog. To restore a backup created
cannot be part of a backup strategy for 4.2+ sharded clusters
that have sharded transactions in progress, as backups created with
mongodump do not maintain the atomicity guarantees
of transactions across shards.
For 4.2+ sharded clusters with in-progress sharded transactions, use one of the following coordinated backup and restore processes which do maintain the atomicity guarantees of transactions across shards: