Re: [Duplicity-talk] Rsync backend, --write-batch-only

[edgar . soldin]

On 05.11.2012 03:34, Yann Hamon wrote:
> Hello,
> 
> I am trying to backup a folder from my computer to a remote, encrypted
> folder on my server. However, the folder is fairly big (several 10GB),
> and would take several days to upload - changes would also take quite a
> while to upload, due to my slow DSL uplink.
> 
> I have an OpenBSD router with root access and a SSD that I planned to
> use for this - it is silent and always on. I was considering doing the
> following:
> 
> - Running rsync on my computer, using the --only-write-batch parameter
> of rsync. This would generate some sort of "patch" file.
> - Copy this file to my router (should be fairly quick, it's gbit link)
> - Run rsync on my router with --read-batch, while having my main
> computer turned off.
> 
> This would work great, however I'd like my backups to be encrypted, and
> thought Duplicity would be a great tool for this. I've tried running
> duplicity using  --rsync-options="--only-write-batch=path" without success.
> 
> Would there be a way to use Duplicity in this manner?
> Thanks
> 

short answer. no.

long answer... --rsync-options only delivers parameters to rsync backend. rsync 
backend is simply functionality to up/download data to the remote storage. for 
the incrementality if duplicity backup's librsync is used internally, but you 
have no way to influence that.

now the good news.. what you want to achieve is possible. it's just usually 
done another way. here it is:

- backup to local file/network location e.g. your ssd on the router (must be 
big enough to hold _all_ backup data e.g. 3 monthly fulls and daily 
incrementals could be your backup plan)
- then rsync this data to the remote location periodically 

btw. --only-write-batch is of no use to you anyway, because duplicity does only 
backup new/changed data blocks anyway in incremental backups.


..ede/duply.net