dinkel / btr-backup

Small backup scripts for raw files, databases, etc. using Btrfs for snapshots

btr-backup

Small backup scripts for raw files, databases, etc. using Btrfs for snapshots.

The main motivation to write these scripts, was me searching and not finding a simple yet reliable soluting to backup my Docker containers. I started with writing a few lines of code to create a "Docker backup image" and shortly after realized, that these scripts can easily be run standalone.

A Docker image using there scripts can be found here.

Normal usage would be to start a backup job every hour, which all create a new Btrfs snapshot. This is however not a requirement.

The script has a cleanup functionality, that ensures that the latest 12 snapshots are kept, plus one snapshot in each of the last 12 days, plus one each month in the last year and finally one snapshot every year.

Usage

At this early stage, the scripts are a bit rough and are configured using a few environment variables described below. They can either be configured beforehand

$ export BACKUP_ROOT=/mnt/backup

[...]

$ ./backup.sh

or inline

$ BACKUP_ROOT=/mnt/backup ./backup.sh

Most probably you'll need to be root to run these scripts (at a minimum to create the Btrfs snapshots).

Environment variables

BACKUP_ROOT (mandatory)

This defines the local base directory where the backups are stored. Multiple roots can be defined by separating the paths by a colon. At least one such root needs to exist and it should be a Btrfs filesystem (altough technically only the subdirectories need be).

Examples:

$ export BACKUP_ROOT=/mnt/backup

$ export BACKUP_ROOT=/mnt/backup-disk-1:/mnt/backup-disk-2

BACKUP_PROJECT (mandatory)

The backup medium (in my case a USB hard drive) can and should hold different backups from different applications. Therefore BACKUP_PROJECT is the name of a backup "project" and this way acts as a namespace.

Example:

$ export BACKUP_PROJECT=owncloud

BACKUP_FILES_PATHS (optional)

If set as a list of colon-separated absolute paths, the files found inside these paths are rsynced to the backup medium.

Example:

$ export BACKUP_FILES_PATHS=/var/www/data:/var/www/config

BACKUP_MYSQL_HOST (optional)

If set, the script uses mysqldump --all-databases to create a full MySQL database dump. Note that it does not fall back to localhost by default, because this option also acts a trigger for the MySQL backup procedure.

Example:

$ export BACKUP_MYSQL_HOST=localhost

BACKUP_MYSQL_USER (optional, default "root")

This defines the user which reads the PostgreSQL database for dumping.

Example:

$ export BACKUP_MYSQL_USER=admin

BACKUP_MYSQL_PASSWORD (optional, default "")

This defines the password for the aforementioned BACKUP_MYSQL_USER. It defaults to no password.

Example:

$ export BACKUP_MYSQL_PASSWORD=mysecretpassword

BACKUP_POSTGRESQL_HOST (optional)

If set, the script uses pg_dumpall to create a full PostgreSQL database dump. Note that it does not fall back to localhost by default, because this option also acts a trigger for the PostgreSQL backup procedure.

Example:

$ export BACKUP_POSTGRESQL_HOST=localhost

BACKUP_POSTGRESQL_USER (optional, default "postgres")

This defines the user which reads the PostgreSQL database for dumping.

Example:

$ export BACKUP_POSTGRESQL_USER=owncloud

BACKUP_POSTGRESQL_PASSWORD (optional, default "")

This defines the password for the aforementioned BACKUP_POSTGRESQL_USER. It defaults to no password.

Example:

$ export BACKUP_POSTGRESQL_PASSWORD=mysecretpassword

BACKUP_OPENLDAP_HOST (optional)

If set, the script uses ldapsearch to create a full OpenLDAP database dump. In order to use remote backups (like it is done with the databases), the ldapsearch script is used instead of the local-only slapcat. There is a nasty problem when using ldapsearch, that is a possible limit on number of results returned set by the server (please make sure, this is not a problem for you).

Example:

$ export BACKUP_OPENLDAP_HOST=localhost

BACKUP_OPENLDAP_DOMAIN (optional)

If set, this domain is transformed to the base DN that is to be backed up.

Example:

$ export BACKUP_OPENLDAP_DOMAIN=ldap.example.org

This would create the base distinguished name of dc=ldap,dc=example,dc=org.

BACKUP_OPENLDAP_USER (optional, default "admin")

This defines the user which reads the OpenLDAP database for data dumping.

Example:

$ export BACKUP_OPENLDAP_USER=backup_user

Together with the BACKUP_OPENLDAP_DOMAIN this would create the -D (bind DN) of cn=backup_user,dc=ldap,dc=example,dc=org.

BACKUP_OPENLDAP_PASSWORD (optional, default "")

This defines the password for the aforementioned BACKUP_OPENLDAP_USER. It defaults to no password.

Example:

$ export BACKUP_OPENLDAP_PASSWORD=mysecretpassword

BACKUP_OPENLDAP_CONFIG (optional)

OpenLDAP allows (and it is the default nowadays), that the configuration is saved in the LDAP directory structure as well in order to allow interrupt-free configuration changes. These configurations are all saven in the cn=config tree and can be backed up if this option is set. Anything goes, something like true, 1 or yes would be considered good choices.

Example:

$ export BACKUP_OPENLDAP_CONFIG=true

BACKUP_OPENLDAP_CONFIG_USER (optional, default "admin")

This defines the user which reads the OpenLDAP database for config dumping.

Example:

$ export BACKUP_OPENLDAP_CONFIG_USER=config_backup_user

This would create the -D (bind DN) of cn=config_backup_user,cn=config.

BACKUP_OPENLDAP_CONFIG_PASSWORD (optional, default "")

This defines the password for the aforementioned BACKUP_OPENLDAP_CONFIG_USER. It defaults to no password.

Example:

$ export BACKUP_OPENLDAP_CONFIG_PASSWORD=mysecretpassword

Comments / Help / Bugs

I'm eager to hear your comments about this piece of software. If you find a bug or thought of an enhancement, please fork or use the issue tracker.