I used to have a scheme running like that. I still have the shell scripts that, using cron, make backups on a daily (mail, repositories, databases), weekly (/etc and most of/var and/home) and monthly (other files) basis. They compress and encrypt this data and then transmit it via rsync over SSH. (although because of encryption rsync has minimal benefit over copying). The only feature missing is that they should keep a few old backups, but that should be easy to add.
In case you (or anyone else) are interested, I've uploaded them here. They're not completely generic (need to change the encryption addy in backup-functions, the backup server hostname in the other three files; also may need to customise these last three files) but they should be easy to modify. Don't forgot to set up SSH to be able to login automatically (using public key auth) for the user you (and cron) launch these scripts from though. Unless you redirect output to/dev/null cron should also send you a nice overview of the copying.
Anyway, what I'm really replying for: if you or other people are interested in setting up such a simple co-op, I'd be interested in reserving 10 to 15 gigabytes for that purpose.
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In case you (or anyone else) are interested, I've uploaded them here. They're not completely generic (need to change the encryption addy in backup-functions, the backup server hostname in the other three files; also may need to customise these last three files) but they should be easy to modify. Don't forgot to set up SSH to be able to login automatically (using public key auth) for the user you (and cron) launch these scripts from though. Unless you redirect output to /dev/null cron should also send you a nice overview of the copying.
Anyway, what I'm really replying for: if you or other people are interested in setting up such a simple co-op, I'd be interested in reserving 10 to 15 gigabytes for that purpose.