How to export all collections in MongoDB?

Question

I want to export all collections in MongoDB by the command:

mongoexport -d dbname -o Mongo.json

The result is:
No collection specifie

Answer 1

If you're dealing with remote databases you can try these commands given that you don't mind the output being BSON

1. Dump out as a gzip archive

mongodump --uri="mongodb://YOUR_USER_ID:YOUR_PASSWORD@YOUR_HOST_IP/YOUR_DB_NAME" --gzip --archive > YOUR_FILE_NAME

2. Restore (Copy a database from one to another)

mongorestore --uri="mongodb://$targetUser:$targetPwd@$targetHost/$targetDb" --nsFrom="$sourceDb.*" --nsTo="$targetDb.*" --gzip --archive