This documentation is for the end of life version of Percona Server for MongoDB and is no longer supported. You may want to see the current documentation.
Hot Backup¶
Percona Server for MongoDB includes an integrated open-source hot backup system for the default WiredTiger and alternative MongoRocks storage engine. It creates a physical data backup on a running server without notable performance and operating degradation.
Making a backup¶
To take a hot backup of the database in your current dbpath
, do the following:
Make sure to provide access to the backup directory for the
mongod
user:$ chown mongod:mongod <backupDir>
Run the
createBackup
command as administrator on theadmin
database and specify the backup directory.> use admin switched to db admin > db.runCommand({createBackup: 1, backupDir: <backup_data_path}) { "ok" : 1 }
If the backup was successful, you should receive an { "ok" : 1 }
object.
If there was an error, you will receive a failing ok
status
with the error message, for example:
> db.runCommand({createBackup: 1, backupDir: ""})
{ "ok" : 0, "errmsg" : "Destination path must be absolute" }
Streaming hot backups to a remote destination¶
Percona Server for MongoDB enables uploading hot backups to an Amazon S3 or a compatible storage service, such as MinIO.
This method requires that you provide the bucket field in the s3 object:
> use admin
...
> db.runCommand({createBackup: 1, s3: {bucket: "backup20190510", path: <some_optional_path>} })
In addition to the mandatory bucket field, the s3 object may contain the following fields:
Field |
Type |
Description |
---|---|---|
bucket |
string |
The only mandatory field. Names are subject to restrictions described in the Bucket Restrictions and Limitations section of Amazon S3 documentation |
path |
string |
The virtual path inside the specified bucket where the backup will be created. If the path is not specified then the backup is created in the root of the bucket. If there are any objects under the specified path, the backup will not be created and an error will be reported. |
endpoint |
string |
The endpoint address and port - mainly for AWS S3 compatible servers such as the MinIO server. For a local MinIO server, this can be “127.0.0.1:9000”. For AWS S3 this field can be omitted. |
scheme |
string |
“HTTP” or “HTTPS” (default). For a local MinIO server started with the minio server command this should field should contain HTTP. |
useVirtualAddressing |
bool |
The style of addressing buckets in the URL. By default ‘true’. For MinIO servers, set this field to false. For more information, see Virtual Hosting of Buckets in the Amazon S3 documentation. |
region |
string |
The name of an AWS region. The default region is US_EAST_1. For more information see AWS Service Endpoints in the Amazon S3 documentation. |
profile |
string |
The name of a credentials profile in the credentials configuration file. If not specified, the profile named default is used. |
accessKeyId |
string |
The access key id |
secretAccessKey |
string |
The secret access key |
Credentials¶
If the user provides the access key id and the secret access key parameters, these are used as credentials.
If the access key id parameter is not specified then the credentials are loaded from
the credentials configuration file. By default, it is ~/.aws/credentials
.
An example of the credentials file
[default]
aws_access_key_id = ABC123XYZ456QQQAAAFFF
aws_secret_access_key = zuf+secretkey0secretkey1secretkey2
[localminio]
aws_access_key_id = ABCABCABCABC55566678
aws_secret_access_key = secretaccesskey1secretaccesskey2secretaccesskey3
Examples¶
Backup in root of bucket on local instance of MinIO server
> db.runCommand({createBackup: 1, s3: {bucket: "backup20190901500",
scheme: "HTTP",
endpoint: "127.0.0.1:9000",
useVirtualAddressing: false,
profile: "localminio"}})
Backup on MinIO testing server with the default credentials profile
The following command creates a backup under the virtual path “year2019/day42” in the backup bucket:
> db.runCommand({createBackup: 1, s3: {bucket: "backup",
path: "year2019/day42",
endpoint: "sandbox.min.io:9000",
useVirtualAddressing: false}})
Backup on AWS S3 service using default settings
> db.runCommand({createBackup: 1, s3: {bucket: "backup", path: "year2019/day42"}})
See also
- AWS Documentation: Providing AWS Credentials
https://docs.aws.amazon.com/sdk-for-cpp/v1/developer-guide/credentials.html
Restoring data from backup¶
Restoring from backup on a standalone server
To restore your database on a standalone server, stop the mongod
service, clean out the data directory and copy files from the backup directory to the data directory. The mongod
user requires access to those files to start the service. Therefore, make the mongod
user the owner of the data directory and all files and subdirectories under it, and restart the mongod
service.
Run the following commands as root or by using the sudo command
# Stop the mongod service
$ systemctl stop mongod
# Clean out the data directory
$ rm -rf /var/lib/mongodb/*
# Copy backup files
$ cp -RT <backup_data_path> /var/lib/mongodb/
# Grant permissions to data files for the mongod user
$ chown -R mongod:mongod /var/lib/mongodb/
# Start the mongod service
$ systemctl start mongod
Restoring from backup in a replica set
The recommended way to restore the replica set from a backup is to restore it into a standalone node and then initiate it as the first member of a new replica set.
Note
If you try to restore the node into the existing replica set and there is more recent data, the restored node detects that it is out of date with the other replica set members, deletes the data and makes an initial sync.
Run the following commands as root or by using the sudo command
The restore steps are the following:
Stop the
mongod
service:$ systemctl stop mongod
Clean the data directory and then copy the files from the backup directory to your data directory. Assuming that the data directory is
/var/lib/mongodb/
, use the following commands:$ rm -rf /var/lib/mongodb/* $ cp -RT <backup_data_path> /var/lib/mongodb/
Grant permissions to the data files for the
mongod
user$ chown -R mongod:mongod /var/lib/mongodb/
Make sure the replication is disabled in the config file and start the
mongod
service.$ systemctl start mongod
Connect to your standalone node via the
mongo
shell and drop the local database> mongo > use local > db.dropDatabase()
Restart the node with the replication enabled
Shut down the node.
$ systemctl stop mongod
Edit the configuration file and specify the
replication.replSetname
optionStart the
mongod
node:$ systemctl start mongod
Initiate a new replica set
# Start the mongo shell > mongo # Initiate a new replica set > rs.initiate()