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MongoDB Backup and Restore

It's a general need in MongoDB development, to take backups or restore DB with an old backup. DB backup can be done at both DB level and individual Collection level. Let's see how we can perform different backup/restore operations..

DB Backup

Complete DB

Assuming database to backup is "mydb", the best thing is to back it as gzip to save some space on your Server.
mongodump --archive=mydb.2017-09-21.gz --gzip --db mydb
This will create the archive in the directory where you're executing the command.

Another way is to take backup as bson documents.
mongodump -h localhost -p 27017 -d mydb -o C:\mongobackup\20170921
A directory with db name will be created under C:\mongobackup\20170921
In case you have multiple instances running on same server, you can use --host and --port options.

Individual Collection

mongodump --collection myCollection --db mydb
This will create backup with same name as that of collection (myCollection in this case).

Restore Database

Restoring from an archive

mongorestore --gzip --archive=mydb.2017-09-21.gz --db mydb

Restoring from bson

Assuming you took backup in C:\mongobackup\20170921
mongodump -h localhost -p 27017 -db mydb C:\mongobackup\20170921\mydb

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