Home backup scripts
A set of scripts for backing up my Ubuntu laptop and my wife's macbook air to a book-sized Linux that acts as my backup server.
Silently and automatically back-up my and my wife's home directories to a backup server at home and also to the cloud. These are backups to disk. Ignore snapshots or other synchronization because the goal here is to back-up unstructured files and data. Ignore system files because it is pretty easy to reinstall.
- Don't run untrusted software as root.
- Keep more than one backup over time.
Concept of Operation
- Script on client (running non-root) wakes up and checks:
- whether a back-up is in progress, and
- whether it has been long enough that a back-up is needed
- Script lists a directory that is an autofs mount from the server
- If laptop is at home, the mount and therefore the listing works
- Otherwise the script exits.
- Assuming the script is still running, it locks a file and runs the backup
- Backup uses rsync with
--link-destargument to do hard-links for files that have not changed.
- Script on server (running non-root) wakes up periodically and checks whether any new data must be backed up to the Cloud, and then does it.
Backup Server Setup
- Create a "backup" user on the backup server to host the backup share
- Create a user on the backup server for each user home directory to back-up. It is easiest to make the uids match, but there are other ways.
- In the home directory of the backup user, create a sub-directory for each user to be backed up, owned by that user.
- Configure Samba to allow mounts of the backup user's home directory as share backup
- Setup a cloud backup of the backup user's home directory on the backup server
- This cloud backup should not run as root because we don't trust that cloud software vendor with root.
NOTE: I am using SpiderOak and their brand is privacy. If you want to use someone else and get (even better) privacy you can mount the backup user's home directory with encfs, so that the underlying files on disk are encrypted. These encrypted files are the ones you then backup to the cloud.
Create a file
/etc/auto.backup.credswith permissions 0600 with user/password for the backup share.
Create a file
/etc/auto.backup. Mine looks like this:
/home/backup -fstype=cifs,credentials=/etc/auto.backup.creds ://tisa/backup
/etc/auto.masterto refer to it. Here's the line that does it:
/- /etc/auto.backup --timeout=60
Create directory where the mount will occur and adjust permissions:
mkdir /home/backup chown dan:users /home/backup
Restart autofs and test the mount
/etc/init.d/autofs restart ls /home/backup
make installto install this stuff in
Use cron to run
auto_backupperiodically. My crontab looks like this:
rsync this way is nothing new: