[Duplicity-talk] Questions

[wighawag]

Hi,

(sorry for the potential double post)

New to duplicity and this looks like a cool project. I am planning to use
it for backing up to blackblaze b2 storage which duplicity now support.

I have 3 questions :

- Does duplicity do global deduplication like zbackup (http://zbackup.org/)
?
(in that case changing filename, moving... does not affect deduplication)

- Does duplicity ever change or delete files on the repo or does it only
append like zbackup does ? zbackup list it as a feature : "Repository
consists of immutable files. No existing files are ever modified"

- In case of b2 support (or other dumb remote) how much transfer is
performed ?
I suppose duplicity need to download the full archive in order to perform
its deduplication logic, or can it be smarter ?

Thanks

Hi,
New to duplicity and this looks like a cool project. I am planning to use
it for backing up to blackblaze b2 storage which duplicity now support.
- Does duplicity do global deduplication like zbackup (http://zbackup.org/)
?
(in that case changing filename, moving... does not affect deduplication)
- Does duplicity ever change or delete files on the repo or does it only
append like zbackup does ? zbackup list it as a feature : "Repository
consists of immutable files. No existing files are ever modified"
- In case of b2 support (or other dumb remote) how much transfer is
performed ?
I suppose duplicity need to download the full archive in order to perform
its deduplication logic, or can it be smarter ?
Thanks

[e***@web.de]

Post by wighawag
Hi,
(sorry for the potential double post)
New to duplicity and this looks like a cool project. I am planning to use
it for backing up to blackblaze b2 storage which duplicity now support.
- Does duplicity do global deduplication like zbackup (http://zbackup.org/)
?
(in that case changing filename, moving... does not affect deduplication)

no

Post by wighawag
- Does duplicity ever change or delete files on the repo or does it only
append like zbackup does ? zbackup list it as a feature : "Repository
consists of immutable files. No existing files are ever modified"

same. when a file is deleted, a marker is added but the file is still in the older volumes.

Post by wighawag
- In case of b2 support (or other dumb remote) how much transfer is
performed ?
I suppose duplicity need to download the full archive in order to perform
its deduplication logic, or can it be smarter ?

no dedup.

as a rule of thumb
- verify and restore download a complete chain
- all other operations manage to work with the manifest files (to eg. know what to incrementally append), which are usually caches locally

..ede/duply.net

[wighawag]

Thanks for your answer


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