Encrypted Backups

Percona XtraBackup has implemented support for encrypted backups. It can be used to encrypt/decrypt local or streaming backup with xbstream option (streaming tar backups are not supported) in order to add another layer of protection to the backups. Encryption is done with the libgcrypt library.

Creating Encrypted Backups

To make an encrypted backup following options need to be specified (options innobackupex --encrypt-key and innobackupex --encrypt-key-file are mutually exclusive, i.e. just one of them needs to be provided):

Both innobackupex --encrypt-key option and innobackupex --encrypt-key-file option can be used to specify the encryption key. Encryption key can be generated with a command like:

$ openssl rand -base64 24

Example output of that command should look like this:

GCHFLrDFVx6UAsRb88uLVbAVWbK+Yzfs

This value then can be used as the encryption key

Using innobackupex --encrypt-key

Example of the innobackupex command using the innobackupex --encrypt-key should look like this

$ innobackupex --encrypt=AES256 --encrypt-key="GCHFLrDFVx6UAsRb88uLVbAVWbK+Yzfs" /data/backups

Using innobackupex --encrypt-key-file

Example of the innobackupex command using the innobackupex --encrypt-key-file should look like this

$ innobackupex --encrypt=AES256 --encrypt-key-file=/data/backups/keyfile /data/backups

Note

Depending on the text editor used for making the KEYFILE, text file in some cases can contain the CRLF and this will cause the key size to grow and thus making it invalid. Suggested way to do this would be to create the file with: echo -n "GCHFLrDFVx6UAsRb88uLVbAVWbK+Yzfs" > /data/backups/keyfile

Both of these examples will create a timestamped directory in /data/backups containing the encrypted backup.

Note

You can use the innobackupex --no-timestamp option to override this behavior and the backup will be created in the given directory.

Optimizing the encryption process

Two new options have been introduced with the encrypted backups that can be used to speed up the encryption process. These are innobackupex --encrypt-threads and innobackupex --encrypt-chunk-size. By using the innobackupex --encrypt-threads option multiple threads can be specified to be used for encryption in parallel. Option innobackupex --encrypt-chunk-size can be used to specify the size (in bytes) of the working encryption buffer for each encryption thread (default is 64K).

Decrypting Encrypted Backups

Backups can be decrypted with The xbcrypt binary. The following one-liner can be used to encrypt the whole folder:

$ for i in `find . -iname "*\.xbcrypt"`; do xbcrypt -d --encrypt-key-file=/root/secret_key --encrypt-algo=AES256 < $i > $(dirname $i)/$(basename $i .xbcrypt) && rm $i; done

Percona XtraBackup innobackupex --decrypt option has been implemented that can be used to decrypt the backups:

$ innobackupex --decrypt=AES256 --encrypt-key="GCHFLrDFVx6UAsRb88uLVbAVWbK+Yzfs" /data/backups/2015-03-18_08-31-35/

Percona XtraBackup doesn’t automatically remove the encrypted files. In order to clean up the backup directory users should remove the *.xbcrypt files.

Note

innobackupex --parallel can be used with innobackupex --decrypt option to decrypt multiple files simultaneously.

When the files have been decrypted backup can be prepared.

Preparing Encrypted Backups

After the backups have been decrypted, they can be prepared the same way as the standard full backups with the innobackupex --apply-log option:

$ innobackupex --apply-log /data/backups/2015-03-18_08-31-35/

Note

Percona XtraBackup doesn’t automatically remove the encrypted files. In order to clean up the backup directory users should remove the *.xbcrypt files.

Restoring Encrypted Backups

innobackupex has a innobackupex --copy-back option, which performs the restoration of a backup to the server’s datadir

$ innobackupex --copy-back /path/to/BACKUP-DIR

It will copy all the data-related files back to the server’s datadir, determined by the server’s my.cnf configuration file. You should check the last line of the output for a success message:

innobackupex: Finished copying back files.
150318 11:08:13  innobackupex: completed OK!