[ale] encrypted differential backups

[Greg Freemyer]

Jim,

backula and duplicity are fundamentally different, so you need to
decide which methodology fits your needs.

In particular I don't think bacula supports differential backup in the
sub-file sense.

ie. Backula will see an entire file as modified or not modified.  If
modified it will send the entire file to the remote server for backup.

duplicty, rdiff-backup, and a couple others use librsync to look for
changes within the files and only send those deltas to the remote
site, thus conserving bandwidth.

I'm most familiar with rdiff-backup. (I.ve been using it for 7 or so
years).  It does _not_ encrypt data on the remote server, just in
transit via ssh.  rdiff-backup accepts the deltas and recreates a
current version of the backed up files plus deltas to get you backward
to older versions.

duplicity "may" work the reverse in that it would maintain an old
version of the files and deltas to get you to the current version.  I
don't know the pros and cons of the two approaches.

fyi: I backup about half a TB remotely every night with rdiff-backup.
But the data is pretty stable and 10GB of deltas in a day would be a
lot.

Greg

On Mon, Aug 31, 2009 at 8:14 AM, Jim Kinney<jim.kinney at gmail.com> wrote:
> bacula. A backup can be encrypted be the originating host, by the
> storing server or just in transit over the IP connection between the
> two. Or a combination. Supports full, differential and incremental
> backups. Can be scripted to support automatic push restores. Supports
> a large set of storage systems from SAN/NAS, other large local or
> remote drive arrays, tape libraries, etc. Also provides reporting
> daily (or per job) for status.
>
> Note: If remote site is not secure, encryption of the data in storage
> is not important. However, the ability to push new data over an
> encrypted tunnel would certainly be a good thing.
>
> On Sun, Aug 30, 2009 at 9:03 PM, Jim Popovitch<jimpop at gmail.com> wrote:
>> I'm looking for an open source way to periodically (cron) archive
>> differential file system changes to an encrypted format (tarball) that
>> can be pushed out to a possibly-not-so-secure remote site (s3).
>>
>> ideas?
>>
>> -Jim P.
> --
> James P. Kinney III
> Actively in pursuit of Life, Liberty and Happiness