Backup Methods of mongodb

Mongodb provides the below  backup  strategies:

• Back Up with MongoDB Cloud Manager or Ops Manager
• Backup by Copying Underlying Data Files
• Backup with mongodump

Backup with MongoDB Cloud Manager or Ops Manager( Enterprise editions  only and required the licences )

      MongoDB Cloud Manager or Ops Manager continually backs up MongoDB replica sets and sharded clusters by reading the plop data from  MongoDB servers. 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.

Pros:

Fully managed backup. Have confidence in your backup strategy with continuous incremental backup, cross-cluster  snapshots, and point-in-time recovery engineered for MongoDB.

Sharded cluster snapshots are difficult to achieve with other MongoDB backup methods.

cons:

   Support only enterprise editions  (required the mongodb  enterprise licence )

Backup by Copying Underlying Data Files(EC2 Snapshots)

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.

Pros:

Using EBS snapshots, which are block-level incremental snapshots, is probably the best and most efficient way to protect MongoDB in the EC2 environment.

Snapshot technology allows backing up volumes in high frequency. What’s even more important is that recovery of large data volumes is almost instant. 

Ensure that you copy data from snapshots onto other systems. This ensures that data is safe from site failures.

cons:

This method  does not provide the for incremental backups.

Backup with mongodump

mongodump reads data from a MongoDB database and creates high fidelity BSON files which the mongorestore tool can use to populate a MongoDB database. mongodump and mongorestore are simple and efficient tools for backing up and restoring small MongoDB deployments, but are not ideal for capturing backups of larger systems. mongodump and mongorestore operate against a running mongod process, and can manipulate the underlying data files directly.

Pros:

Provide the consistent of the backups and efficient for small databases .

Cons:

Resource overhead 

 mongodump can adversely affect mongod performance. If your data is larger than system memory, the queries will push the working set out of memory, causing page faults and cause the IO wait on the storage.

Applications can continue to modify data while mongodump captures the output. For replica sets,mongodump provides the --oplog option to include in its output oplog entries that occur during the mongodump operation. This allows the corresponding mongorestore operation to replay the captured oplog. 

No Incremental Backups

This method  does not provide the incremental backups.