Borg is the new generation of attic.

borg init --encryption=keyfile /path/to/repo
borg create -C lz4 /path/to/repo::NAME-YOUR-BACKUP ~/Documents

Free space

Before you start creating backups,please make sure that there is always a good amount of free spaceon the filesystem that has your backup repository (and also on ~/.cache).

Encryption

Default enabled with repokey method.

borg init --encryption=none|repokey|keyfile PATH

When repository encryption is enabled,all data is encrypted using 256-bit AES encryptionand the integrity and authenticity is verified using HMAC-SHA256.

• repokey: key is stored inside the repository (config);
• keyfile: key is stored under ~/.config/borg/keys/;

In both modes, the key is stored in encrypted formand can be only decrypted by providing the correct passphrase.

Do not forget to backup the key (e.g. via borg key export).

For automated backups the passphrase can be specifiedusing the BORG_PASSPHRASE environment variable.

Be careful how you set the environment;using the env command, a system() call or using inline shell scriptsmight expose the credentials in the process list directlyand they will be readable to all users on a system.Using export in a shell script file should be safe, however,as the environment of a process is accessible only to that user.Also, using a shell command may leak the passphrase in shell history file.

For server backup, have a look at borgmatic.

Compression

borg create --compression TYPE

Default is no compression.

• fast repo storage and some compression: lz4
• less fast repo storage and a bit more compression: zlib
• very slow repo storage and high compression: lzma

lz4 is very fast thus preferred.lzma is preferred when the repository is on a remote host with slow (dial-up) connection.

Upgrade from attic

borg upgrade --inplace REPOSITORY

If a backup copy is required, omit the --inplace option.

Hosted Services

• rsync.net also works with scp, rsync, git, etc. Nodes available globally.
• BorgBase dedicated borg repository hosting with specific APIs. It also offers a free plan (5 GB and 2 repos), and paid plans are cheaper than rsync.net. Nodes available in US and EU.