Frequently asked questions¶
- Which platforms are supported?
- Currently Linux, FreeBSD and MacOS X are supported.
- Can I backup VM disk images?
- Yes, the deduplication technique used by
Atticmakes sure only the modified parts of the file are stored.
- Which file attributes are preserved?
The following attributes are preserved:
- Time of last modification (nanosecond precision with Python >= 3.3)
- User ID of owner
- Group ID of owner
- Unix Permission
- Extended attributes (xattrs)
- Access Control Lists (ACL) on Linux, OS X and FreeBSD
- BSD flags on OS X and FreeBSD
- How can I specify the encryption passphrase programmatically?
- The encryption passphrase can be specified programmatically using the ATTIC_PASSPHRASE environment variable. This is convenient when setting up automated encrypted backups. Another option is to use key file based encryption with a blank passphrase. See Repository encryption for more details.
- When backing up to remote servers, is data encrypted before leaving the local machine, or do I have to trust that the remote server isn’t malicious?
- Yes, everything is encrypted before leaving the local machine.
- If a backup stops mid-way, does the already-backed-up data stay there? I.e. does Attic resume backups?
- Yes, during a backup a special checkpoint archive named
<archive-name>.checkpointis saved every 5 minutes containing all the data backed-up until that point. This means that at most 5 minutes worth of data needs to be retransmitted if a backup needs to be restarted.