Shulou(Shulou.com)06/01 Report--

1. Cold standby of mongodb

The cold backup of mongodb is to copy the relevant files of the library. Therefore, to shut down the server before the cold standby, use the command to smoothly shut down server.

> use admin > db.shutdownServer () or you can make MongoDB write data to cache through fsync, and then copy backup > use admin > db.runCommand ({"fsync": 1, "lock": 1})

After the library is locked, the insert data command is executed and no response is found. After the backup, unlock (to prevent the loss of uncached data due to power outages or other reasons at this time).

> use admin > db.$cmd.sys.unlock.findOne () > db.currentOp ()

If currentOp only returns {"inprog": []} result, it is unlocked successfully. The data is not written to the database until it is unlocked.

You can also use the following command to unlock:

> use admin > db.fsyncUnlock ()

2. Hot standby of mongodb

You can use the two tools provided by MongoDB to achieve backup and recovery without stopping the service. These two tools can be seen in MongoDB's bin directory: mongodump/mongorestor

1. Common command grid

Mongodump-h IP-- port PORT-u UserName-p Password-d DB_name-c Collection_Name-- authenticationDatabase AuthDB_name-o BackupPath [--gzip]

If you do not specify a user, you can omit-u and-p; omit-h to export local databases by default; omit-- port default port 27017; omit-d to export all databases by default.

2. Export all databases

[root@localhost mongodb] # mongodump-h 127.0.0.1-o / home/user01/backup/

3. Export the specified database

[root@localhost mongodb] # mongodump-h 192.168.1.108-d tank-o / home/user01/backup

Third, mongorestore restores the database

1. Common command formats

Mongorestore-h IP-- port PORT-u UserName-p Password-d DB_Name-c Collection_Name-- drop BackupPath_Or_FileName

-- drop means that all records are deleted and then restored.

2. Restore all databases to mongodb

[root@localhost mongodb] # mongorestore / home/user01/backup/ # the path here is the backup path of all libraries

3. Restore the specified database

[root@localhost mongodb] # mongorestore-d tank/ home/user01/backup/tank/ # tank the backup path of this database [root@localhost mongodb] # mongorestore-d tank_new / home/user01/backup/tank/ # will tank and these two commands in the tank_new database can be used to back up and restore the database. The file format is json and bson. Unable to write to table backup or restore.

4. Mongoexport exports the table, or some fields in the table

1. Common command formats

Mongoexport-h IP-- port port-u user name-p password-d database-c table name-f field-Q conditional export-csv-o file name

The above parameters are easy to understand, so let's focus on:

-f export refers to the field, divided by font size,-f name,email,age export name,email,age these three fields

-Q can be derived from the root query condition, and data with a uid of 100 can be exported from-Q'{"uid": "100"}'

-- csv indicates that the exported file format is csv, which is useful because most relational databases support csv and have something in common here.

2. Export the whole table

[root@localhost mongodb] # mongoexport-d tank-c users-o / home/user01/backup/tank/users.dat

3. Export some fields in the table

[root@localhost mongodb] # mongoexport-d tank-c users-- csv-f uid,name,sex-o tank/users.csv

4. Dare to produce data according to the conditions

[root@localhost mongodb] # mongoexport-d tank-c users-Q'{uid: {$gt:1}}'- o tank/users.json

5. Mongoimport imports a table or some fields in the table

1. Common command formats

1) restore non-csv files exported from the whole table

Mongoimport-h IP-- port port-u user name-p password-d database-c table name-upsert-- drop file name

To highlight-- upsert, other parameters have been mentioned in the above command,-- upsert inserts or updates existing data.

2) restore the export files of some fields

Mongoimport-h IP-- port port-u user name-p password-d database-c table name-upsertFields field-drop file name

-- upsertFields root-- same as upsert.

3) restore the exported csv file

Mongoimport-h IP-- port port-u user name-p password-d database-c table name-type type-headerline-- upsert-- drop file name

In the above three cases, there can be other permutations and combinations.

2. Restore the exported table data

[root@localhost mongodb] # mongoimport-d tank-c users-- upsert tank/users.dat

3. Import the table data of some fields

[root@localhost mongodb] # mongoimport-d tank-c users-- upsertFields uid,name,sex tank/users.dat

4. Restore the csv file

[root@localhost mongodb] # mongoimport-d tank-c users-type csv-headerline-file tank/users.csv

VI. Examples

[root@meteor] # mkdir backup [root@meteor] # mongodump-h localhost-- port 27027-d person-o backup/-u person-p 1232016-08-04T10:09:36.701+0800writing person.p1 to2016-08-04T10:09:36.701+0800done dumping person.p1 (1 document) [root@meteor] # ls backup/person/p1.bson p1.metadata.json [root@meteor] # mongo localhost:27027/admin-u admin-pMongoDB shell version: 3.2.8Enter password:connecting to : localhost:27027/admin > use personswitched to db person > show collectionsp1 > db.p1.drop () true > show collections > exitbye [root@meteor] # mongorestore-h localhost-- port 27027-d person backup/person/-u person-p 1232016-08-04T10:11:42.234+0800building a list of collections to restore from backup/person dir2016-08-04T10:11:42.235+0800reading metadata for person.p1 from backup/person/p1.metadata.json2016-08-04T10:11:42.256+0800restoring person.p1 from backup/person/p1.bson2016 -08-04T10:11:42.268+0800restoring indexes for collection person.p1 from metadata2016-08-04T10:11:42.268+0800finished restoring person.p1 (1 document) 2016-08-04T10:11:42.268+0800done [root@meteor ~] # [root@meteor ~] # mongo localhost:27027/person-u person-p 123MongoDB shell version: 3.2.8connecting to: localhost:27027/person > show collectionsp1 > db.p1.find () {"_ id": ObjectId ("57a2a28aa6d4803a1c952529") "name": "thompson", "gender": "male" "age": "24"} [root@meteor ~] # rm backup/*-rf [root@meteor ~] # mongoexport-h localhost-- port 27027-u person-p 123-d person-c p1-o backup/person.p1.dat2016-08-04T10:22:06.773+0800connected to: localhost:270272016-08-04T10:22:06.773+0800exported 1 record [root@meteor ~] # mongoimport-h localhost-port 27027-u person-p 123-d person-c p2-upsert backup / person.p1.dat2016-08-04T10:25:16.414+0800connected to: localhost:270272016-08-04T10:25:16.434+0800imported 1 document [root@meteor ~] # mongo localhost:27027/person-u person-p 123MongoDB shell version: 3.2.8connecting to: localhost:27027/person > show collectionsp1p2 > db.p2.find () {"_ id": ObjectId ("57a2a28aa6d4803a1c952529") "name": "thompson", "gender": "male", "age": "24"} > db.p1.find () {"_ id": ObjectId ("57a2a28aa6d4803a1c952529"), "name": "thompson", "gender": "male", "age": "24"} {"_ id": ObjectId ("57a2a9c43f2b617cfdd64c63"), "name": "eric", "gender": "female" "age": 18} {"_ id": ObjectId ("57a2bfe38381eac036252b7c"), "name": "test1", "gender": "male", "age": 20} > exitbye [root@meteor ~] # rm-rf backup/* Ls backup/ [root@meteor ~] # mongodump-h localhost-- port 27027-d person-o backup/-u person-p 123 backup all tables in the entire library 2016-08-04T12:36:36.321+0800writing person.p1 to2016-08-04T12:36:36.321+0800writing person.p2 to2016-08-04T12:36:36.322+0800done dumping person.p1 (3 documents) 2016-08-04T12:36:36.322+0800done dumping person.p2 (1 document) [root@meteor ~] # Ls backup/person [root@meteor ~] # ls backup/person/p1.bson p1.metadata.json p2.bson p2.metadata.json [root@meteor ~] # mongo localhost:27027/person-u person-p 123MongoDB shell version: 3.2.8connecting to: localhost:27027/person > db.p1.drop () true > db.p2.drop () true > show collections > exitbye [root@meteor ~] # mongorestore-h localhost-port 27027-d person-c p1 backup/person/p1.bson-u person-p 123 Note: you can restore the specified table 2016-08-04T12:38:55.541+0800checking for collection data in backup/person/p1.bson2016-08-04T12:38:55.541+0800reading metadata for person.p1 from backup/person/p1.metadata.json2016-08-04T12:38:55.560+0800restoring person.p1 from backup/person/p1.bson2016-08-04T12:38:55.639+0800restoring indexes for collection person.p1 from metadata2016-08-04T12:38:55.640+0800finished restoring person.p1 (3 documents) 2016 separately. -08-04T12:38:55.641+0800done [root@meteor ~] # mongo localhost:27027/person-u person-p 123MongoDB shell version: 3.2.8connecting to: localhost:27027/person > show tablesp1 > db.p1.find () {"_ id": ObjectId ("57a2a9c43f2b617cfdd64c63") "name": "eric", "gender": "female", "age": 18} {"_ id": ObjectId ("57a2bfe38381eac036252b7c"), "name": "test1", "gender": "male", "age": 20} {"_ id": ObjectId ("57a2a28aa6d4803a1c952529"), "name": "thompson", "gender": "male", "age": "24"} > exitbye [root@meteor ~]

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